{"title":"Vacuum Tubes","description":"\u003ctable class=\"collection-table\" style=\"width: 100%; border:none!important;\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/tube-basics-and-frequently-asked-questions\" target=\"_blank\"\u003eTube Basics and FAQ\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/grading-matching\" target=\"_blank\"\u003eGrading and Matching\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/vacuum-tube-warranty-information\" target=\"_blank\"\u003eTube Warranty \u0026amp; Return Policy\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/cryogenically-treated-vacuum-tubes\" target=\"_blank\"\u003eCryogenic Treating\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/test-equipment\" target=\"_blank\"\u003eTube Testing Equipment\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/why-we-dont-sell-certain-brands\" target=\"_blank\"\u003eWhy We Don't Sell Certain Brands\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n","products":[{"product_id":"gold-lion-kt77-el34","title":"Gold Lion KT77 \/ EL34","description":"\u003ch1\u003e\u003cstrong\u003eGold Lion KT77\u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003e\u003cstrong\u003eNotice: We supply the very finest KT77s, and our testing is the best, period. They are all burned in before testing and matching. These tubes are NOT as dependable as the Mullard EL34.  \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHowever, people really seem to like them....a lot. Our job is to tell you the facts. \u003c\/strong\u003e\u003c\/p\u003e\n\u003ch4\u003eOther dealers won't tell you the truth. Upscale Audio will.  \u003cbr\u003e\n\u003c\/h4\u003e\n\u003cp\u003eA modern re-creation of the legendary Genalex KT77. Produced in Russia.  Great mids, smooth, airy highs, incredible bass, wonderful 3D presence, and that natural glory you'd expect in an EL34. \u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eA quick note on this tube:\u003c\/strong\u003e\u003c\/em\u003e These tubes seem to take a bit longer to break in than some other power tubes, so if they sound a little lightweight in the bass, you have to give them time. Some guys are reporting at least 100 hours before the fully come into their own.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above is for a single tube. Includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at [as an example] 6500 micromhos, the next one at 8600 micromhos. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"No Cryo","offer_id":21828961413,"sku":"GOLD LION KT77","price":76.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21828961349,"sku":"GOLD LION KT77 C","price":84.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/99a0efb2e3065bde05217c1f37b764fa.jpg?v=1741632776"},{"product_id":"mullard-el34","title":"Mullard EL34","description":"\u003ch1\u003eMullard EL-34\u003c\/h1\u003e\nA modern re-creation of the classic Mullard. Produced in Russia by New Sensor. We've been playing these in everything from the \u003cstrong\u003ePrimaLuna amps\u003c\/strong\u003e to the Manley Classic 250s, and they sound great. Nice warmth, plenty of detail, but will retain a little more top end extension than the \u003cstrong\u003eSED Winged C.\u003c\/strong\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cdiv align=\"center\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/xU4Df87DRFs\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at [as an example] 6500 micromhos, the next one at 8600 micromhos. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Mullard","offers":[{"title":"No Cryo","offer_id":21828962309,"sku":"MUL EL34","price":55.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21828962181,"sku":"MUL EL34 C","price":63.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/b8be5f0c3ef8564712440bcd29a9b740.jpg?v=1741632774"},{"product_id":"tung-sol-kt120","title":"Tung-Sol KT120","description":"\u003ch1\u003e\u003cstrong\u003eTung-Sol KT120 \u003c\/strong\u003e\u003c\/h1\u003e\nSuper cool KT88 variant made by New Sensor in Russia. This tube is a drop-in replacement for KT88s... no special re-wiring required! The KT120 is rated to have a plate dissipation of 60W... compared with the 35W of the 6550, the 42W of the KT88, that's a lot of juice!\n\u003cp\u003e\u003cstrong\u003eThe KT120 also draws more filament current from your amp's power transformer.\u003c\/strong\u003e Before you buy them, check with your amp's manufacturer to make sure you've got enough headroom. \u003cbr\u003e\u003cbr\u003e\u003cstrong\u003eOne quick note:\u003c\/strong\u003e The KT120 is about 1\/2\" taller than a typical KT88, so if your KT88s are already a tight squeeze in your equipment, you may want to measure to make sure you have enough clearance before placing an order.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cdiv align=\"center\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/jhfpVs9gtaQ\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at, as an example, 6500 micro Ohms, the next one at 8600 micro \u003cspan\u003eOhms\u003c\/span\u003e. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21828968965,"sku":"TUNGSOL-KT120","price":79.95,"currency_code":"USD","in_stock":false},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21828968901,"sku":"TUNGSOL-KT120-C","price":88.95,"currency_code":"USD","in_stock":false},{"title":"Audio Research Matched \/ No Cryo","offer_id":31952959045692,"sku":"TUNGSOL-KT120-ARC","price":97.95,"currency_code":"USD","in_stock":true},{"title":"Audio Research Matched \/ Yes Cryo","offer_id":31952959111228,"sku":"TUNGSOL-KT120-ARC-C","price":105.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/65f330021faf204616863c2448b73715.jpg?v=1741632772"},{"product_id":"electro-harmonix-kt88","title":"Electro-Harmonix KT88","description":"\u003ch1\u003e\n\u003cstrong\u003eElectro-Harmonix KT88\u003c\/strong\u003e \u003c\/h1\u003e\n\u003cp\u003eThere were a few versions of this tube created before what's available now. I waited for the first few batches to go through... experience has taught me that many times the first couple of batches suck as they begin to iron out the kinks. Sometimes, they NEVER get it right, and I don't want you to be the one we experiment with. Well... they got this one right... reliable and rugged, with great clarity and pop. \u003c\/p\u003e\n\u003cp\u003eFlat out a great tube.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at [as an example] 6500 \u003cspan\u003emicro \u003c\/span\u003e\u003cspan\u003eOhms\u003c\/span\u003e, the next one at 8600 \u003cspan\u003emicro \u003c\/span\u003e\u003cspan\u003eOhms\u003c\/span\u003e. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Electro-Harmonix","offers":[{"title":"No Cryo","offer_id":21828969797,"sku":"EH KT88","price":69.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21828969733,"sku":"EH KT88 C","price":77.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/e667405ac1679155b047b40677f809da.jpg?v=1741632771"},{"product_id":"gold-lion-kt88","title":"Gold Lion KT88","description":"\u003ch1\u003eGold Lion KT-88\u003c\/h1\u003e\nRussian re-issue of the legendary Genalex KT88. These guys rock... They've been working great in all applications we've tried them in, and haven't had a single complaint. Read web forums and you'll see tons of praise for this tube. Sound is beautifully balanced... airy highs, gorgeous mids, deep dynamic bass. I know we shouldn't care about looks... but who am I kiddin'... with the side getters and Genalex-inspired silkscreening... they look bitchin' too!\u003cbr\u003e\u003cbr\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above is for a single tube.\u003c\/strong\u003e Includes matching in any quantity you need at no extra charge.\u003c\/p\u003e\n\u003cdiv align=\"center\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/ISZYEdajkrI\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at [as an example] 6500 micromhos, the next one at 8600 micromhos. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"No Cryo","offer_id":43030474162360,"sku":"GOLD LION KT88","price":99.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":43030474195128,"sku":"GOLD LION KT88 C","price":107.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/43b1c3c1c553d9e475b1c6e6e2a696c3.jpg?v=1741632769"},{"product_id":"gold-lion-kt66","title":"Gold Lion KT66","description":"\u003ch1\u003eGold Lion KT66\u003c\/h1\u003e\nRussian re-issue of the legendary Genalex. This one get's Uncle Kevvy's seal of approval. Built to the highest standards and is very reliable. Great substitite for the 6L6GC, but consult your amp's manufacturer: The KT66 has a higher dissippation than its 5881 and 6L6GC counterparts, and if your amp's bias range is set low you may not be able to bias these. Sound is lively and dynamic with a smooth natural midrange, with body and a holographic, 3D presence. All around a beautifully balanced sound.\n\u003cdiv align=\"center\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/HSTrBgzL-2g\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eA quick note on this tube:\u003c\/strong\u003e\u003c\/em\u003e Some folks report these KT66s take a bit longer to burn in than other power tubes. So if they seem a little light in the bottom end, just give it time.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above is for a single tube. Includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"No Cryo","offer_id":21828983173,"sku":"GOLD LION KT66","price":77.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21828983109,"sku":"GOLD LION KT66 C","price":85.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/fe8daaaf50470a381697b0bfaf51bdfd.jpg?v=1741632768"},{"product_id":"sovtek-5881","title":"Sovtek 5881","description":"\u003ch1\u003eSovtek 5881\u003c\/h1\u003e\n\n\u003cp\u003eThe workhorse of the 5881 family. This is most commonly used 5881 on the market today. If you have a 5881-based amplifier, chances are this was the tube that came stock. It has solid, military-spec build quality, which makes it very sturdy and dependable. If you just want a tube that is just plain going to work and work and work and not cost big $$$, this is the tube for you. They sound pretty darn good too.\u003c\/p\u003e\n\u003cp\u003eThe 5881 can be used as a replacement for the 6L6GC, however it is a lower dissipation tube, which means less power, and you may need to back off the bias slightly depending on your amplifier. Consult your amp's owner's manual first. To be honest... if your amp can use the 6L6GC, I'd stick with that.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e","brand":"Sovtek","offers":[{"title":"No Cryo","offer_id":21828985861,"sku":"SOV 5881","price":39.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21828985797,"sku":"SOV 5881 C","price":47.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/31710c54f3326638c33ca53665ebb68e.jpg?v=1741632767"},{"product_id":"tung-sol-5881","title":"Tung-Sol 5881","description":"\u003ch1\u003e\n\u003cstrong\u003eTung-Sol 5881\u003c\/strong\u003e \u003c\/h1\u003e\n\u003cp\u003eNew production tube made by New Sensor in the Reflektor factory in Russia. Gotta 5881 amp and you're sick of using the same old Sovteks? Folks are really getting into this current production homage to the legendary Tung-Sol. Similar in looks to the original U.S. version, and folks \"in the know\" say they sound similar too.\u003c\/p\u003e\n\u003cp\u003eThe 5881 can be used as a replacement for the 6L6GC, however it is a lower dissipation tube, which means less power, and you may need to back off the bias slightly depending on your amplifier. Consult your amp's owner's manual first. To be honest... if your amp can use the 6L6GC, I'd stick with that.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"No Cryo","offer_id":21828986565,"sku":"TUNGSOL 5881","price":47.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21828986501,"sku":"TUNGSOL 5881 C","price":55.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/1d603a996e79042e50f7641725560d5d.jpg?v=1741632766"},{"product_id":"electro-harmonix-6sn7","title":"Electro-Harmonix 6SN7","description":"\u003ch1\u003e\n\u003cstrong\u003eElectro-Harmonix 6SN7\u003c\/strong\u003e \u003c\/h1\u003e\n\u003cp\u003eCurrent production tube made by New Sensor in Russia. Great tube. These tubes have been testing really low in noise and microphony, so if you have a preamp that is very sensitive, this may be the way to go.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003cstrong\u003e \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003cstrong\u003e \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\" rel=\"noopener noreferrer\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003eLogo quality may vary from picture above. Price includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Electro-Harmonix","offers":[{"title":"Kevin's Stash \/ No Cryo","offer_id":29530429915196,"sku":"EH 6SN7 KS","price":53.95,"currency_code":"USD","in_stock":false},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530429980732,"sku":"EH 6SN7 KS C","price":61.95,"currency_code":"USD","in_stock":false},{"title":"Platinum Grade \/ No Cryo","offer_id":21829018181,"sku":"EH 6SN7 P","price":43.95,"currency_code":"USD","in_stock":false},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21829018117,"sku":"EH 6SN7 P C","price":51.95,"currency_code":"USD","in_stock":false},{"title":"Gold Grade \/ No Cryo","offer_id":41664338559160,"sku":"EH 6SN7 G","price":33.95,"currency_code":"USD","in_stock":false},{"title":"Gold Grade \/ Yes Cryo","offer_id":41664338591928,"sku":"EH 6SN7 G C","price":41.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/c3f9134cde793f0993469e2a867a3f69.jpg?v=1741632765"},{"product_id":"russian-6as7","title":"Russian 6AS7G \/ 6N13S","description":"\u003ch1\u003e\u003cstrong\u003eRussian 6AS7G\u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eThis is the power tube used in the Feliks Audio Elise \u0026amp; Euforia headphone amplifiers. Purchase is restricted to owners of those products.\u003c\/p\u003e\n\u003cp\u003eEarly production Russian tubes. Manufactured in the Svetlana Electron Devices (Winged \"C\") factory in St. Petersburg. Some are branded 6H13C or 6N13S, which was the Soviet military designation for 6AS7, some are marked as Svetlana or Sovtek, but they're all from the same place.\u003c\/p\u003e","brand":"Russian","offers":[{"title":"Default Title","offer_id":21829182469,"sku":"6AS7","price":99.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/206e849646b3fdfc7eb03b65aa0b03a0.jpg?v=1741632763"},{"product_id":"russian-6c33-b","title":"Russian 6C33-B","description":"\u003ch1\u003eRussian 6C33-B\u003c\/h1\u003e\n\u003cp\u003eFrom Russia with love. Need some replacement power tubes for your BAT? We got 'em in stock ready to go. Made in the Ulyanov factory in Russia.\u003c\/p\u003e\n\u003cp\u003eMost amps that use this tube do not require matching, as it is somewhat difficult to match this tube, but we still put each tube through a rigorous screening process and test them on our Amplitrex T1000 tube tester. Most 6C33s you see out there now are used; these are first-quality, brand new still in factory boxes.\u003c\/p\u003e\n\u003cp\u003eLabel and box may vary from image above. \u003cstrong\u003ePrice includes matching in any quantity you order, no extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Russian","offers":[{"title":"Default Title","offer_id":21829183749,"sku":"6C33","price":129.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/d918f53b33f7da0400efa0d6e2d4a4ca.jpg?v=1741632762"},{"product_id":"sovtek-5ar4","title":"Sovtek 5AR4","description":"\u003ch1\u003e\u003cstrong\u003eSovtek 5AR4\u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eCurrent production made in Russia. Excellent and dependable tube. Most current products using the 5AR4 as a rectifier use this tube or the Shuguang (Chinese). The Chinese is more dependable.\u003cbr\u003e\u003c\/p\u003e","brand":"Sovtek","offers":[{"title":"No Cryo","offer_id":21829208965,"sku":"SOV-5AR4","price":34.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21829208837,"sku":"SOV-5AR4-C","price":42.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/ae3c05c43f539e1a504d57e878c739a6.jpg?v=1575409198"},{"product_id":"electro-harmonix-300b","title":"Electro-Harmonix 300B Gold Grid","description":"\u003ch1\u003e\u003cstrong\u003eElectro-Harmonix 300B \u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eThis is the default bitchin' tube that will not give you problems, sounds wonderful, and priced right. This is the most commonly used OEM tube for manufacturers of 300B amps because of it's low price and rugged build. There are many versions out there, this is the best \"gold grid\" version. Factory matched.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Electro-Harmonix","offers":[{"title":"No Cryo","offer_id":21829226693,"sku":"EH 300B","price":169.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21625681739836,"sku":"EH 300B CRYO","price":178.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/7b5b4de62098b2a003bf514e056577ec.jpg?v=1741632761"},{"product_id":"russian-6h30pi","title":"Sovtek 6H30Pi","description":"\u003ch1\u003eSovtek 6H30Pi\u003c\/h1\u003e\n\u003cp\u003eThere are two types of 6H30 tubes currently being produced. The Sovtek brand which have the chrome pins (listed here), and the Electro Harmonix Gold pin. They are the same tube from the same factory. Don’t get your panties in a bunch over which is better, as the gold plating is laid over the chrome plating. They are both terrific. What is most important is how they test.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eYou guys already know that Upscale Audio is the only place that the Audio Research factory people give a thumbs up to\u003c\/strong\u003e. That’s because we actually have our power tubes matched properly and have the highest Gm, and that \u003cstrong\u003eevery small signal tube like the 6H30 is not just measured, but listened to in a special phono stage test circuit by using headphones.\u003c\/strong\u003e That, my friends, is the only way to get the blackest blacks in your system.\u003c\/p\u003e\n\u003cp\u003eWe deal with some fairly picky customers that want to make sure that their expensive ARC preamps, phono stages, and amps are as close to perfection as possible. For that customer we have 6H30’s in a grade called “ARC Select”.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThis grade has four distinguishing characteristics:\u003c\/strong\u003e\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003eThe transconductance measurements will be as high as possible, resulting in a tube with the longest life.\u003c\/li\u003e\n\u003cli\u003eInternal balance between the two triodes of the tube will be as tight as possible, within 15% (triode balance on a 6H30 can easily vary by 50%)\u003c\/li\u003e\n\u003cli\u003eThe microphony will be the absolute lowest possible, tested in a moving coil phonostage test circuit with 60dB of gain.\u003c\/li\u003e\n\u003cli\u003eThe noise will be the absolute lowest possible while being pushed in the same moving coil phonstage test circuit.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003ePlatinum grade will be a fine tube for most people.\u003c\/strong\u003e\u003c\/em\u003e If you want to assure everything in your system is PERFECT, then use ARC Select. Remember that the tubes are the actual amplifying device you are listening to. They are everything. More than those cables you bought, or that power conditioner. That’s why Upscale Audio is the place that ARC owner’s go. Nobody does what we do.\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003ePlease note: There are a finite number of ARC Select grade available.\u003c\/b\u003e If the website does not let you place your order, call us at 909-931-9686 and we can put you on a waiting list.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThis tube is not a replacement for 6922 or any other tube type.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" rel=\"noopener noreferrer\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003c\/strong\u003e\u003c\/a\u003e \u003c\/strong\u003eLabel quality may vary from picture above. Prices includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Sovtek","offers":[{"title":"Gold Grade \/ No Cryo","offer_id":21829851397,"sku":"SOV 6H30 G","price":53.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":21829851333,"sku":"SOV 6H30 G C","price":61.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ No Cryo","offer_id":21829851525,"sku":"SOV 6H30 P","price":63.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21829851461,"sku":"SOV 6H30 P C","price":71.95,"currency_code":"USD","in_stock":true},{"title":"ARC Select \/ No Cryo","offer_id":21829851653,"sku":"SOV 6H30 ARS","price":83.95,"currency_code":"USD","in_stock":true},{"title":"ARC Select \/ Yes Cryo","offer_id":21829851589,"sku":"SOV 6H30 ARS C","price":101.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/bef5a94dc8715908fa356e14732092c1.jpg?v=1741632707"},{"product_id":"gold-lion-ecc83-b759","title":"Gold Lion ECC83 \/ B759 \/ 12AX7","description":"\u003ch1\u003eGold Lion ECC83 \/ 12AX7\u003c\/h1\u003e\nLet's face it... NOS 12AX7's are getting scarce. When that happens, the price goes up. The good news? The quality of current production 12AX7's is getting better and better. The latest Russian re-issue is a perfect example. These Gold Lion 12AX7 re-issues sound incredible: A full, glorious midrange with great texture and liquid detail, extended yet controlled highs, tight bass.\n\u003cp\u003eVery quiet and low in microphonics. Due to the larger plate structure, if you're the kind of guy who likes to thwack their tubes with their fingernails... these will likely reward you with a loud \"PING!\" through the speakers. The solution? Don't thwack them with your fingernails!\u003c\/p\u003e\n\u003cdiv align=\"center\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/sCu_zGckuvY\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cp\u003eThese tubes tested extremely low in noise and microphonics across the board, so we do not have any Driver\/Buffer Grade.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/upscaleaudio.pro\/pages\/grading-matching\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21830120005,"sku":"GOLDLION12AX7 P","price":79.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21830119941,"sku":"GOLDLION12AX7 P C","price":87.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41659594899640,"sku":"GOLDLION12AX7 G","price":69.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":41659594932408,"sku":"GOLDLION12AX7 G C","price":77.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530422509628,"sku":"GOLDLION12AX7 KS","price":89.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530422542396,"sku":"GOLDLION12AX7 KS C","price":97.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/f5d4de2dd4e47e30f56f67395842edd2.jpg?v=1741632688"},{"product_id":"gold-lion-ecc82-b749","title":"Gold Lion ECC82 \/ B749 \/ 12AU7","description":"\u003ch1\u003eGold Lion ECC82 \/ 12AU7\u003c\/h1\u003e\nIncredible current production re-issue of the legendary Genalex. Very low noise and microphonics. These tubes have beautiful and dynamic midrange texture, airy highs, controlled, tight bass. Excellent resolution.\n\u003cp\u003eThese tubes tested extremely low in noise and microphonics across the board, so we do not have any Driver Grade.\u003c\/p\u003e\n\u003cdiv align=\"center\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/HS2tX1gqzqU\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21830123077,"sku":"GOLDLION12AU7 P","price":79.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21830123013,"sku":"GOLDLION12AU7 P C","price":87.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41659639791800,"sku":"GOLDLION12AU7 G","price":69.95,"currency_code":"USD","in_stock":false},{"title":"Gold Grade \/ Yes Cryo","offer_id":41659639824568,"sku":"GOLDLION12AU7 G C","price":77.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530422444092,"sku":"GOLDLION12AU7 KS","price":89.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530422476860,"sku":"GOLDLION12AU7 KS C","price":97.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/2144cef5f6e5a118eb4f46a665b870f2.jpg?v=1583876942"},{"product_id":"tung-sol-6l6gc-str","title":"Tung-Sol 6L6GC-STR","description":"\u003ch1\u003e\n\u003cstrong\u003eTung-Sol 6L6GC-STR\u003c\/strong\u003e \u003c\/h1\u003e\n\u003cp\u003eNew production tube made by New Sensor in the Reflektor factory in Russia. Perfect drop-in replacement for any 6L6GC amplifier. They're very well-built, and sound great with a little more midrange clarity than the SED, which has a little warmer character.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"No Cryo","offer_id":21830128581,"sku":"TUNGSOL6L6GC","price":48.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21830128517,"sku":"TUNGSOL6L6GC C","price":56.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/5b56c2f4a86fe820355a788895b4efcf.jpg?v=1741632687"},{"product_id":"tung-sol-6sn7gtb","title":"Tung-Sol 6SN7GTB","description":"\u003ch1\u003e\u003cstrong\u003eTung-Sol 6SN7GTB \u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eRe-issue, made by New Sensor in Russia. New Sensor purchased the the Tung-Sol name and trademark, and have begun making new production tubes, using the Tung-Sol brand. These tubes sound great, they stay quiet and have been solid and reliable. Great detail and depth.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003cstrong\u003e \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003cstrong\u003e \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\" rel=\"noopener noreferrer\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"Gold Grade \/ No Cryo","offer_id":21830453573,"sku":"TUNG-SOL 6SN7 G","price":59.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":21830453445,"sku":"TUNG-SOL 6SN7 G CRYO","price":67.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ No Cryo","offer_id":21830453701,"sku":"TUNG-SOL 6SN7 P","price":69.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21830453637,"sku":"TUNG-SOL 6SN7 P CRYO","price":77.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530422378556,"sku":"TUNG-SOL 6SN7 KS","price":84.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530422411324,"sku":"TUNG-SOL 6SN7 KS C","price":92.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/33f7029ba22142b39556659fbfb7461e.jpg?v=1741632625"},{"product_id":"electro-harmonix-6922-gold-pin","title":"Electro-Harmonix 6922 Gold Pin","description":"\u003ch1\u003e\u003cstrong\u003eElectro-Harmonix 6922 Gold Pin\u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003e\u003cstrong\u003eThis is the gold pin version of the 6H23 Type 2\u003c\/strong\u003e. Like the Type 2s, they are slightly relaxed... just a smidge warmer than the Type 3. If you have a Sonic Frontiers or ARC they will help you have a more palpable midrange. Will also alleviate some of that harshness found in some of those 90's vintage Sovteks with the silverish plates.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade. \u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\" rel=\"noopener noreferrer\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Electro-Harmonix","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21830510341,"sku":"EH6922GP P","price":41.95,"currency_code":"USD","in_stock":false},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21830510149,"sku":"EH6922GP P C","price":49.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41664368279736,"sku":"EH6922GP G","price":31.95,"currency_code":"USD","in_stock":false},{"title":"Gold Grade \/ Yes Cryo","offer_id":41664368312504,"sku":"EH6922GP G C","price":39.95,"currency_code":"USD","in_stock":false},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530422181948,"sku":"EH6922GP KS","price":51.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530422214716,"sku":"EH6922GP KS C","price":59.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/747697ae9dc2db6ca2aa95f02a0704ef.jpg?v=1741632618"},{"product_id":"russian-6h30pi-gold-pin","title":"Electro-Harmonix 6H30Pi Gold Pin","description":"\u003ch1\u003eElectro-Harmonix 6H30Pi Gold Pin\u003c\/h1\u003e\n\u003cp\u003eThere are two types of 6H30 tubes currently being produced. The Sovtek brand which have the chrome pins, and the Electro Harmonix Gold pin (listed here). They are the same tube from the same factory. Don’t get your panties in a bunch over which is better, as the gold plating is laid over the chrome plating. They are both terrific. What is most important is how they test. You guys already know that Upscale Audio is the only place that the Audio Research factory people give a thumbs up to. That’s because we actually have our power tubes matched properly and have the highest Gm, and that every small signal tube like the 6H30 is not just measured, but listened to in a special phono stage test circuit by using headphones. That, my friends, is the only way to get the blackest blacks in your system.\u003c\/p\u003e\n\u003cp\u003eWe deal with some fairly picky customers that want to make sure that their expensive ARC preamps, phono stages, and amps are as close to perfection as possible. For that customer we have 6H30’s in a grade called “ARC Select”.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThis grade has four distinguishing characteristics:\u003c\/strong\u003e\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003eThe transconductance measurements will be as high as possible, resulting in a tube with the longest life.\u003c\/li\u003e\n\u003cli\u003eInternal balance between the two triodes of the tube will be as tight as possible, within 15% (triode balance on a 6H30 can easily vary by 50%)\u003c\/li\u003e\n\u003cli\u003eThe microphony will be the absolute lowest possible, tested in a moving coil phonostage test circuit with 60dB of gain.\u003c\/li\u003e\n\u003cli\u003eThe noise will be the absolute lowest possible while being pushed in the same moving coil phonstage test circuit.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003ePlatinum grade will be a fine tube for most people.\u003c\/strong\u003e\u003c\/em\u003e If you want to assure everything in your system is PERFECT, then use ARC Select. Remember that the tubes are the actual amplifying device you are listening to. They are everything. More than those cables you bought, or that power conditioner. That’s why Upscale Audio is the place that ARC owner’s go. Nobody does what we do.\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003ePlease note: There are a finite number of ARC Select grade available.\u003c\/b\u003e If the website does not let you place your order, call us at 909-931-9686 and we can put you on a waiting list.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThis tube is not a replacement for 6922 or any other tube type.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" rel=\"noopener noreferrer\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003c\/strong\u003e\u003c\/a\u003e \u003c\/strong\u003eLabel quality may vary from picture above. Prices includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Electro-Harmonix","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21830513413,"sku":"EH 6H30 P","price":77.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21830513349,"sku":"EH 6H30 P C","price":85.95,"currency_code":"USD","in_stock":false},{"title":"Gold Grade \/ No Cryo","offer_id":21830513285,"sku":"EH 6H30 G","price":67.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":21830513221,"sku":"EH6H30 G C","price":75.95,"currency_code":"USD","in_stock":true},{"title":"ARC Select \/ No Cryo","offer_id":21830513541,"sku":"EH 6H30 ARS","price":89.95,"currency_code":"USD","in_stock":false},{"title":"ARC Select \/ Yes Cryo","offer_id":21830513477,"sku":"EH 6H30 ARS C","price":97.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/8379e84e42db047d5f97de5caac6d5a7.jpg?v=1741632616"},{"product_id":"tung-sol-12au7w-6189","title":"Tung-Sol 12AU7W \/ 6189","description":"\u003ch1\u003e\u003cstrong\u003eTung-Sol 12AU7W\/6189  \u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eFrom Russia with love. These current production tubes are quiet, they sound great, and are dependable... giving them Uncle Kevvy's seal of approval. A great choice for any 12AU7\/ECC82 circuit.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e \u003cem\u003eNot available for this tube.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" rel=\"noopener noreferrer\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21830519685,"sku":"TUNG-SOL 12AU7 P","price":39.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":25415521936,"sku":"TUNG-SOL 12AU7 P CRYO","price":47.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41659654144184,"sku":"TUNG-SOL 12AU7 G","price":29.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":41659654176952,"sku":"TUNG-SOL 12AU7 G CRYO","price":37.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530421461052,"sku":"TUNG-SOL 12AU7 KS","price":49.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530421526588,"sku":"TUNG-SOL 12AU7 KS C","price":57.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/8daecd69dde4f382928bd91ddccf1905.jpg?v=1741632615"},{"product_id":"tung-sol-12ax7-ecc803-s-gold-pin","title":"Tung-Sol 12AX7 \/ ECC803-S Gold Pin","description":"\u003ch1\u003e\n\u003cstrong\u003eTung-Sol 12AX7 \/ ECC83\u003c\/strong\u003e \u003c\/h1\u003e\n\u003cp\u003ePrice of NOS 12AX7s got you down? This new production Tung-Sol 12AX7 made in Russia is the answer! Very low noise and microphonics, but if you've got a really high-gain phonostage the new \u003cstrong\u003eMullard re-issue\u003c\/strong\u003e might be a better choice. Gorgeous mids, beautiful dynamics, and a nice 3D soundstage. If you're looking for a smidge more relaxed top end, give the \u003cstrong\u003eMullard re-issue\u003c\/strong\u003e a try. \u003cstrong\u003ePrice is for a single tube.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eA quick note on this tube:\u003c\/strong\u003e\u003c\/em\u003e The filaments on these Tung-Sols are almost completely encased in the plate structure. So if you don't see them glowing as bright as some of your other 12AX7s... don't sweat it. It's normal for this tube.\u003c\/p\u003e\n\u003cp\u003eThese tubes tested extremely low in noise and microphonics across the board, so we do not have any Driver Grade.\u003c\/p\u003e\n\u003cdiv align=\"center\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/O6WEMt4LJj8\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e \u003cem\u003eNot available for this tube.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\" rel=\"noopener noreferrer\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21830527173,"sku":"TUNG-SOL 12AX7 GP P","price":55.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21830527109,"sku":"TUNG-SOL 12AX7 GP P C","price":63.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41664357793976,"sku":"TUNG-SOL 12AX7 GP G","price":45.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":41664357826744,"sku":"TUNG-SOL 12AX7 GP G C","price":53.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530421362748,"sku":"TUNG-SOL 12AX7 GP KS","price":65.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530421395516,"sku":"TUNG-SOL 12AX7 GP KS C","price":73.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/c83835f4c12fea4e1905c52e264c04cb.jpg?v=1741632613"},{"product_id":"tung-sol-kt-150","title":"Tung-Sol KT150","description":"\u003ch1\u003eTung-Sol KT150\u003c\/h1\u003e\n\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/9EzArd-P5Bg?rel=0\" frameborder=\"0\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003eThe overall sound of the KT150 is thunderously powerful. The bass is tight, full, and precise with a neutral midrange and transparent high end clarity. The dynamics are unlike anything we have ever heard before. This is truly the Tyrannosaurus Rex of beam tetrodes.\u003c\/p\u003e\n\u003cdiv\u003e\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003eWhat the manufacturer says:\u003c\/strong\u003e \"With the new KT150, Tung-Sol continues to lead in the audio power tube, power game. After the introduction of the highly successful Tung-Sol KT120, Russia's premier vacuum tube inventor, Valery Krivtsov, in collaboration with Irusha Bitukova and a team of ExpoPUL tube designers, set to work in our laboratories to develop an even more powerful audio output tube.\u003cbr\u003e\u003cbr\u003eWith a massive plate dissipation of 70 watts, the Tung-Sol KT150 is the most powerful octal beam tetrode ever produced. The Tung-Sol KT150 glass envelope is a special egg shaped balloon that was developed to improve thermal dissipation and maintain a superior vacuum for the best sound. The fact that the glass envelope has no flat sides means the Tung-Sol KT150 has no problems with microphonics.\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003cstrong\u003e\u003cem\u003eBecause each KT150 consumes 2.0A of filament current (more than the KT88 and 6550), we recommend contacting your equipment manufacturer to ensure your power supply is capable of powering this tube.\u003c\/em\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAdditionally, this tube is 5-1\/2\" from bottom of base (not including pins) to the top of the glass. Make sure your amp has at least 6-1\/2\" of clearance from top of the tube socket to the overhead limit. There must be room allowed for both tube installation and cooling. Also please understand that the plate structure of this tube is such that it almost completely obscures the heater element of the tube from view... so you will most likely not see these tubes glowing; this is normal.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at, as an example, 6500 micro Ohms, the next one at 8600 micro \u003cspan\u003eOhms\u003c\/span\u003e. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch2\u003eA nice note from our customer, Jeff Wheaton\u003c\/h2\u003e\n\u003cp\u003eGreetings, I am sure you are aware the KT150 drifts, when new, even after \"alleged\" matching by other sellers AKA ebay or other. Your burn-in solves this problem.\u003c\/p\u003e\n\u003cp\u003eProspective kt 150 buyers know this....many of the KT 150 Quads bought from small time operations cannot be used....they won't balance. I work at a custom tube amp builder. We now are ONLY buying your tubes or our customers MUST buy your KT 150'S or we won't set the AC\/DC balance for them. Several customers have brought unusable \"new KT 150\" quads to us which after 10 hours, drifted so far, they would not balance....now unusable......and they saved 15.00\/tube. Share this and save philes some money, and they will get longer tube life, and better sound.\u003c\/p\u003e\n\u003cp\u003eAudiophiles, believe Uncle Kevin...his tubes are better. The 150's match so nice now......Only get \"Real Matched tubes\".........Jeff\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":640997130256,"sku":"TUNG-SOL KT150","price":139.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21830999493,"sku":"TUNG-SOL KT150 CRYO","price":147.95,"currency_code":"USD","in_stock":true},{"title":"Audio Research Matched \/ No Cryo","offer_id":31785176563772,"sku":"TUNG-SOL KT150 ARC","price":149.95,"currency_code":"USD","in_stock":true},{"title":"Audio Research Matched \/ Yes Cryo","offer_id":31785176531004,"sku":"TUNG-SOL KT150 ARC CRYO","price":157.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/9a9cec073f15580586e408277d8a4fa4.jpg?v=1741632501"},{"product_id":"tung-sol-12at7","title":"Tung-Sol 12AT7","description":"\u003ch1\u003e\u003cstrong\u003eTung-Sol 12AT7 \u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eMade in Russia. A great tube at a great price. Given that small tubes like this last typically between 5,000 and 10,000 hours, it may make sense to spend just a little more and get the vintage Mullard CV4024 made in Great Britain. That tube is selling at a low price right now and will be $150 each at some point.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\" rel=\"noopener noreferrer\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21831033285,"sku":"TUNG-SOL 12AT7 P","price":39.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21831033221,"sku":"TUNG-SOL 12AT7 P C","price":47.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41664401440952,"sku":null,"price":29.95,"currency_code":"USD","in_stock":false},{"title":"Gold Grade \/ Yes Cryo","offer_id":41664401473720,"sku":null,"price":37.95,"currency_code":"USD","in_stock":false},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530420052028,"sku":"TUNG-SOL 12AT7 KS","price":49.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530420084796,"sku":"TUNG-SOL 12AT7 KS C","price":59.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/d18a0700d19149f2152c967f1bd34c9d.jpg?v=1741632499"},{"product_id":"gold-lion-12at7-b739","title":"Gold Lion ECC81 \/ B739 \/ 12AT7","description":"\u003ch1\u003eGold Lion 12AT7 \/ B739\u003c\/h1\u003e\n\u003cp\u003eA fine tube made today in Russia. Gold pins. When we grade them for low noise and microphony they are really good. Very linear with a super top end and bass. But they cannot be compared to the real \u003ca href=\"\/12at7-ecc81-6201-cv4024\/mullard-cv4024-12at7\/\"\u003eMullard CV4024\u003c\/a\u003e made in Great Britain.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21831037829,"sku":"GOLD LION 12AT7 P","price":79.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21831037701,"sku":"GOLD LION 12AT7 P C","price":87.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41664351830200,"sku":"GOLD LION 12AT7 G","price":69.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":41664351862968,"sku":"GOLD LION 12AT7 G C","price":77.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530419986492,"sku":"GOLD LION 12AT7 KS","price":89.95,"currency_code":"USD","in_stock":false},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530420019260,"sku":"GOLD LION 12AT7 KS C","price":97.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/6df053eed244f11f85bc39603a3c5814.jpg?v=1741632498"},{"product_id":"tung-sol-5751-gold-pin-reissue-made-in-russia","title":"Tung-Sol New Production 5751 Gold Pin","description":"\u003ch1\u003e\u003cstrong\u003eTung-Sol 5751 Gold Pin \u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eExcellent tube made in Russia, and a godsend for people needing 5751 at a great price. These used to be branded Electro Harmonix but are now branded Tung-Sol. Platinum grade $24.95 gold grade $19.95\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eA note on the 5751:\u003c\/em\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eSometimes\u003c\/em\u003e a 5751 can be used in lieu of a 12AX7. Some folks (guitar guys typically) that have gear that come equipped with 12AX7's will sub a 5751. They do this specifically because it colors the sound and changes the way their amp performs, as they look for ways to \"distort.\" This is a matter of taste as the 5751 is a lower gain tube than the 12AX7. If someone tells you to use a 5751 because they like it, make sure it's the same piece of gear. A lower gain tube can, depending on the circuit, operate perfectly. However, in some extreme cases, the lower gain can cause high distortion and in some cases not even work properly.\u003c\/p\u003e\n\u003cp\u003e5751 tubes do not have a \"sound\" that is particular to that tube, any more than 12AX7's have a \"sound\". It depends on who made the 5751 and when, the operating condition of the tube, and the circuit it's going into. Any other assumptions or statements about the merits of that tube are silly.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"%%GLOBAL_ShopPath%%\/pages\/Testing-Small-Signal-Tubes.html\" target=\"_blank\" rel=\"noopener noreferrer\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"Gold Grade \/ No Cryo","offer_id":21831149893,"sku":"TS5751-G","price":49.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":25415563088,"sku":"TS5751-GC","price":57.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ No Cryo","offer_id":21831149957,"sku":"TS5751-P","price":59.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":25415564560,"sku":"TS5751-PC","price":67.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530419691580,"sku":"TS5751-KS","price":69.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530419724348,"sku":"TS5751-KSC","price":77.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/066150e72af315701ade10a70d59181f.jpg?v=1583879418"},{"product_id":"electro-harmonix-kt90","title":"Electro-Harmonix KT90","description":"\u003ch1\u003e\n\u003cstrong\u003eElectro-Harmonix KT90\u003c\/strong\u003e \u003c\/h1\u003e\n\u003cp\u003eThe Electro Harmonix KT90-EH tube is a drop-in for any KT88 or 6550 tube... bias your amp just as you would a KT88 and you're good to go! Sonically they are true to the Electo Harmonix brand; clear top end that is open but not bright or tizzy, tight bottom end, and a clear midrange that is not hard or clinical. They are not a super warm tube.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at [as an example] 6500 micro Ohms, the next one at 8600 \u003cspan\u003emicro \u003c\/span\u003e\u003cspan\u003eOhms\u003c\/span\u003e. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Electro-Harmonix","offers":[{"title":"No Cryo","offer_id":21831300805,"sku":"EH KT90","price":88.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831300741,"sku":"EH KT90 C","price":96.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/51da5d811b4f3c4b7dd7078737839537.jpg?v=1741632491"},{"product_id":"mullard-new-production-gz34-5ar4-rectifier","title":"Mullard New Production GZ34 \/ 5AR4 Rectifier","description":"\u003cp\u003e\u003cstrong\u003eMullard GZ34 \/ 5AR4 - \u003c\/strong\u003eNew production made in Russia.  This tube is well-built, sounds great, and has been a great rectifier for folks looking to break free from the typicak Sovtek or Shuguang offerings. Please do not buy this thinking it's going to sound like a NOS Mullard... it won't.  But... it's also a fraction of the price!\u003c\/p\u003e","brand":"Mullard","offers":[{"title":"No Cryo","offer_id":21831305221,"sku":"MUL-GZ34","price":65.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831305157,"sku":"MUL-GZ34-C","price":73.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/0352da729a6be3822bc7e8bdcd285df1.jpg?v=1583877659"},{"product_id":"mullard-new-production-cv4004-12ax7","title":"Mullard New Production CV4004 \/ 12AX7","description":"\u003cp\u003e\u003cstrong\u003eMullard CV4004 \/ 12AX7\u003c\/strong\u003e - Price of NOS 12AX7s got you down? This new re-issue of the famous Mullard CV4004 made in Russia is the answer to your woes! This is a short plate version of New Sensor's excellent Mullard 12AX7.  Very low noise and microphony make this tube an excellent candidate for many touchy preamps and phonostage applications. By all reports, these are even quieter than the long plates, so if you have a difficult circuit, this tube may be your solution.\u003c\/p\u003e\u003cp\u003eLike it's long plate brother, the CV4004 has a smooth midrange. Some folks have reported them to be a smidge relaxed on top. If you want something with a little more lively presentation, try the new production \u003cstrong\u003eTung-Sol 12AX7.\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cem\u003e\u003cstrong\u003eA quick note on this tube:\u003c\/strong\u003e\u003c\/em\u003e The filaments on these tubes are almost completely encased in the plate structure. So if you don't see them glowing as bright as some of your other 12AX7s... don't sweat it. It's normal for this tube.\u003c\/p\u003e\u003cp\u003eThis tube tested extremely low in noise and microphonics across the board, so we do not have any Driver Grade.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"Mullard","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21831306629,"sku":"MULLARDNS CV4004 P","price":46.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21831306565,"sku":"MULLARDNS CV4004 P C","price":54.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41659670397112,"sku":"MULLARDNS CV4004 G","price":36.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":41659670429880,"sku":"MULLARDNS CV4004 G C","price":44.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530419429436,"sku":"MULLARDNS CV4004 KS","price":56.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530419462204,"sku":"MULLARDNS CV4004 KS C","price":64.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/17f1164adb746827e880226caf45354c.jpg?v=1741632490"},{"product_id":"sovtek-6550we","title":"Sovtek 6550WE","description":"\u003cp\u003e\u003cstrong\u003eSovtek 6550WE\u003c\/strong\u003e - From Russia with love.  If you have an Audio Research amp, this is the tube you want.  These tubes are very rugged, reliable, and sound great.  They have a little bump in the midrange, tight bass, good top end extension. \u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ePricing above is for a single tube.\u003c\/strong\u003e Includes matching in any quantity you need at no extra charge.\u003c\/p\u003e\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at [as an example] 6500 micromhos, the next one at 8600 micromhos. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Sovtek","offers":[{"title":"No Cryo","offer_id":21831479941,"sku":"SOV 6550WE","price":81.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831479813,"sku":"SOV 6550WE C","price":89.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/90f3e5e6e0d4a485e08ddbcc78a981b9.jpg?v=1741632472"},{"product_id":"tung-sol-new-production-5ar4-rectifier","title":"Tung-Sol New Production 5AR4 Rectifier","description":"\u003ch1\u003e\u003cstrong\u003eTung-Sol 5AR4 \u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eNew production made in Russia. This tube is well-built, sounds great, and has been a great rectifier for folks looking to break free from the typicak Sovtek or Shuguang offerings. Great performance and reliability.\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"No Cryo","offer_id":21831631685,"sku":"TUNGSOL 5AR4","price":55.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831631621,"sku":"TUNGSOL 5AR4 C","price":63.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/c753ff2311cafbde6352e38afcb7a5a0.jpg?v=1741632459"},{"product_id":"mullard-kt88","title":"Mullard KT88","description":"\u003ch1\u003e\u003cstrong\u003eMullard KT-88\u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eBefore buying any power tubes you need to know this: Upscale Audio pays more for our tubes than other companies. We pay the factory to pre-test for us, and give us the top 50% of production. Upscale Audio tubes will last longer; period. Nobody pays attention to your tube purchase like Uncle Kevvy. Incredible tube! These sound very much like the Gold Lion KT88 to me. They come out of the same factory. Stunning mids, extended top end, and tight bass.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above is for a single tube.\u003c\/strong\u003e Includes matching in any quantity you need at no extra charge.\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at [as an example] 6500 micromhos, the next one at 8600 micromhos. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Mullard","offers":[{"title":"No Cryo","offer_id":21831674885,"sku":"MULLARD KT88","price":74.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831674693,"sku":"MULLARD KT88 C","price":82.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/88baff2edf530b614996b134da3ed869.jpg?v=1741632458"},{"product_id":"tung-sol-el34b","title":"Tung-Sol EL34B","description":"\u003ch1\u003eTung-Sol EL-34B\u003c\/h1\u003e\nProduced in Russia by New Sensor, in the Reflektor factory. They've been making some incredible tubes here lately, and this new re-issue is no exception. We've been playing these in everything from the \u003cstrong\u003ePrimaLuna amps\u003c\/strong\u003e to the Manley Classic 250s, and they sound great. Nice warmth, plenty of detail, great bass.\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e This applies especially to power tubes like EL34, 6550, KT88’s, etc. Two tubes can be brand new in the original box, with one testing at, as an example, 6500 \u003cspan\u003emicro Ohms\u003c\/span\u003e, the next one at 8600 micro Ohms. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Tung-Sol","offers":[{"title":"No Cryo","offer_id":21831678277,"sku":"TUNG-SOL EL34B","price":52.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831678149,"sku":"TUNG-SOL EL34B CRYO","price":60.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/0c37a20156641178314721d20096a647.jpg?v=1741632457"},{"product_id":"mullard-6bq5-el84-new-production","title":"Mullard 6BQ5 \/ EL84 New Production","description":"\u003ch1\u003eMullard 6BQ5\/EL-84\u003c\/h1\u003e\n\nMade in Russia.  New production re-issue from New Sensor. Gorgeous mids, punchy bass, these guys are sure to please even the most demanding boutique EL84 amp owner.\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Mullard","offers":[{"title":"No Cryo","offer_id":21831681861,"sku":"MULLARD EL84","price":37.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831681797,"sku":"MULLARD EL84 C","price":45.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/eacbd59173645be1297247400655d7e2.jpg?v=1741632456"},{"product_id":"gold-lion-n709-el84-new-production","title":"Gold Lion N709 \/ EL84 New Production","description":"\u003ch1\u003eGenalex Gold Lion N709\/EL-84\u003c\/h1\u003e\nMade in Russia. New production re-issue from New Sensor. Gorgeous mids, punchy bass, these guys are sure to please even the most demanding boutique EL84 amp owner.\n\u003cp\u003eIf your amp is cathode bias, it will run these tubes too hard, causing them to fail prematurely! Use the early production Russia 6H14 instead.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"No Cryo","offer_id":25514307664,"sku":"GOLD LION EL84","price":49.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":29705621667900,"sku":"GOLD LION EL84 C","price":57.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/dd73ba7f2ba4e0cf16ccee7aebafccf7.jpg?v=1741632455"},{"product_id":"gold-lion-u77-5ar4-new-production-rectifier","title":"Gold Lion U77 \/ 5AR4 New Production Rectifier","description":"\u003ch1\u003eGold Lion U77 \/ 5AR4\u003c\/h1\u003e\n\u003cstrong\u003eNote: This tube is not suited to PrimaLuna amps.\u003c\/strong\u003e\n\u003cp\u003eNew production made in Russia. This tube is well-built, smooth, refined, and balanced for the very best high-end audio sound. A great alternative to the typical OEM offerings. Please do not buy this thinking it's going to sound like a NOS Genalex U77... it won't. But... it's also a fraction of the price!\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"No Cryo","offer_id":21831685253,"sku":"GOLD LION 5AR4","price":69.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":21831685189,"sku":"GOLD LION 5AR4 C","price":77.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/eee63859c244cb0629ebba507b80c0f2.jpg?v=1741632454"},{"product_id":"electro-harmonix-12ay7-6072a","title":"Electro-Harmonix 12AY7 \/ 6072A","description":"\u003ch1\u003e\u003cstrong\u003eElectro-Harmonix 12AY7\u003c\/strong\u003e\u003c\/h1\u003e\n\u003cp\u003eLooking for a good, reliable, current production 12AY7? Here it is! Made in Russia. Very quiet, transparent, detailed.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\" rel=\"noopener noreferrer\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"Electro-Harmonix","offers":[{"title":"Platinum Grade \/ No","offer_id":21831813893,"sku":"EH12AY7 P","price":36.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes","offer_id":32495810150460,"sku":"EH12AY7 P C","price":44.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No","offer_id":21831813765,"sku":"EH12AY7 G","price":26.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes","offer_id":32495810117692,"sku":"EH12AY7 G C","price":34.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No","offer_id":29530418479164,"sku":"EH12AY7 KS","price":46.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes","offer_id":32495810183228,"sku":"EH12AY7 KS C","price":54.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/4e1357232d2bfb6cd46a41fd807cfee2.jpg?v=1741632448"},{"product_id":"mullard-new-production-12au7-ecc82","title":"Mullard New Production 12AU7 \/ ECC82","description":"\u003cp\u003e\u003cstrong\u003eMullard 12AU7 \/ ECC82\u003c\/strong\u003e - Current production Russian re-issue. These tubes are quiet, they sound great, and are dependable... giving them Uncle Kevvy's seal of approval. A great choice for any 12AU7\/ECC82 circuit.\u003c\/p\u003e\n\u003cp\u003eThis tube tested extremely low in noise and microphonics across the board, so we do not have any Driver Grade.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"Mullard","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21831879813,"sku":"MULLARD 12AU7 P","price":35.95,"currency_code":"USD","in_stock":false},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21831879749,"sku":"MULLARD 12AU7 P C","price":43.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ No Cryo","offer_id":41659662008504,"sku":"MULLARD 12AU7 G","price":25.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":41659662041272,"sku":"MULLARD 12AU7 G C","price":33.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530418282556,"sku":"MULLARD 12AU7 KS","price":45.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530418315324,"sku":"MULLARD 12AU7 KS C","price":53.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/8933ab466ff30b9a4963c48ef8dfce29.jpg?v=1741632446"},{"product_id":"mullard-new-production-12at7-ecc81","title":"Mullard New Production 12AT7 \/ ECC81","description":"\u003cp\u003e\u003cstrong\u003eMullard 12AT7 \/ ECC81\u003c\/strong\u003e - Current production Russian re-issue. These tubes are quiet, they sound great, and are dependable... giving them Uncle Kevvy's seal of approval. A great choice for any 12AT7\/ECC81 circuit.\u003c\/p\u003e\n\u003cp\u003eThis tube tested extremely low in noise and microphonics across the board, so we do not have any Driver Grade.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDriver\/Buffer grade -\u003c\/strong\u003e Lowest noise but not the lowest in microphony. Triode balance will be similar to Gold grade.\u003cbr\u003e\u003cem\u003eThis grade is only suitable for use in the driver stage of an amplifier, or the output\/buffer stage of a DAC or CD Player.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIf you have a preamp or phonostage, you need at least Gold grade.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"Mullard","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":21831884869,"sku":"MULLARD 12AT7 P","price":31.95,"currency_code":"USD","in_stock":false},{"title":"Platinum Grade \/ Yes Cryo","offer_id":21831884805,"sku":"MULLARD 12AT7 P C","price":39.95,"currency_code":"USD","in_stock":false},{"title":"Gold Grade \/ No Cryo","offer_id":41664395247800,"sku":"MULLARD 12AT7 G","price":29.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":41664395280568,"sku":"MULLARD 12AT7 G C","price":27.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":29530418217020,"sku":"MULLARD 12AT7 KS","price":43.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":29530418249788,"sku":"MULLARD 12AT7 KS C","price":51.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/7f8f66bb63efa20772f3c15b58bfa4fd.jpg?v=1741632444"},{"product_id":"gold-lion-6v6gt-cv511","title":"Gold Lion 6V6GT \/ CV511","description":"\u003ch1\u003eGold Lion 6V6GT\u003c\/h1\u003e\nA modern re-creation of the legendary Genalex 6V6GT\/CV511. Produced in Russia by New Sensor. Feedback from customers say this tube embodies the quintessential \"6V6\" sound with amazing tone and reliability.\n\u003cp\u003e\u003cstrong\u003ePricing above is for a single tube. Includes matching in any quantity you need at no extra charge.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/our-tube-testing-equipment\"\u003e\u003cstrong\u003eAll power tubes are Platinum Screened \u0026amp; Tested\u003c\/strong\u003e\u003c\/a\u003e to the highest standards, including a 72-hour burn in process, and testing at real-world voltages.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvery power tube is different.\u003c\/strong\u003e Two tubes can be brand new in the original box, with one testing at [as an example] 6500 micromhos, the next one at 8600 micromhos. Both tubes would be considered \"new\" by the factory, and not defective. While the weaker tube isn’t \"defective,\" it will certainly have a shorter life. So if you pay 10% less, you might get a tube with a significantly shorter life. The big lie from manufacturers of tube equipment and tube dealers themselves is that they “reject” these tubes. It’s not true. You can imagine the nightmare that would create for the tube factory if people are sending back 50% - 80% of the tubes that get shipped, coming back in all kinds of condition.\u003c\/p\u003e\n\u003cp\u003eAs the owner of Upscale Audio, a company that has supplied tubes into over 50,000 components, and someone obsessed with treating your amp like it’s my amp, I can tell you in no uncertain terms the factory doesn’t take them back. The only tubes they will take back are tubes that have shorts, gas, or measure BELOW the minimum number they assign for that tube type (it varies from type to type, so don’t bother trying to figure that out).\u003c\/p\u003e\n\u003cp\u003eI’ve overcome that issue for you. I can say with calm assurance that we pay the factories more for our tubes than any other tube seller, and we ensure that we receive the absolute cream of the crop. This flies against the logic of how to run a business: The way you make money is to pay less for the goods you sell! That’s what most ANY business owner will tell you. We also don’t sell certain brands of tubes because while they might be cheap and sometimes good, they can be more trouble than they're worth. We pass on a lot of money as a result.\u003c\/p\u003e\n\u003cp\u003eUpscale Audio is the only dealer that does what we do on a grand scale, and have a deep understanding of high end tube electronics. We’re the only dealer that manufacturers give a thumbs-up to, and recommend to their customers. And I promise you only the best.\u003c\/p\u003e\n\u003cp\u003e- Kevin Deal\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"No Cryo","offer_id":31987637682236,"sku":"GOLD LION 6V6GT","price":57.95,"currency_code":"USD","in_stock":true},{"title":"Yes Cryo","offer_id":31987637715004,"sku":"GOLD LION 6V6GT C","price":65.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/gold-lion-6v6gt.jpg?v=1741631393"},{"product_id":"primaluna-12ax7-1","title":"PrimaLuna -12AX7-","description":"\u003ch1\u003ePrimaLuna 12AX7\u003c\/h1\u003e\n\u003cp\u003eThis is the stock 12AX7 as found in the award-winning \u003cstrong\u003ePrimaLuna\u003c\/strong\u003e products. This tube is quiet, reliable, and sounds great.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePricing above is for a single tube,\u003c\/strong\u003e and includes matching in any quantity you need at no extra charge. Tubes are tested to Platinum Grade standards.\u003c\/p\u003e","brand":"PrimaLuna","offers":[{"title":"Default Title","offer_id":41204642807992,"sku":"PL-12AX7-G2","price":59.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/files\/DSC_9855.jpg?v=1742406179"},{"product_id":"gold-lion-ecc83-12ax7-cv4004","title":"Gold Lion ECC83 \/ 12AX7 \/ CV4004","description":"\u003ch1\u003eGold Lion ECC83 \/ 12AX7 \/ CV4004\u003c\/h1\u003e\n\u003cp\u003eThese tubes tested extremely low in noise and microphonics across the board, so we do not have any Driver\/Buffer Grade.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlatinum grade -\u003c\/strong\u003e The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGold grade -\u003c\/strong\u003e Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"\/grading-and-matching-small-signal-tubes\" target=\"_blank\"\u003e\u003cstrong\u003eClick here for a more in depth discussion on how we grade tubes.\u003cbr\u003e\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003ePrice includes matching in any quantity you need at \u003cstrong\u003eno extra charge.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Gold Lion","offers":[{"title":"Gold Grade \/ No Cryo","offer_id":40189180051640,"sku":"GOLDLIONCV4004 G","price":59.95,"currency_code":"USD","in_stock":true},{"title":"Gold Grade \/ Yes Cryo","offer_id":40189180084408,"sku":"GOLDLIONCV4004 GC","price":67.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ No Cryo","offer_id":40189180117176,"sku":"GOLDLIONCV4004 P","price":69.95,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":40189180149944,"sku":"GOLDLIONCV4004 PC","price":77.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":40189180182712,"sku":"GOLDLIONCV4004 KS","price":89.95,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":40189180215480,"sku":"GOLDLIONCV4004 KSC","price":97.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/gltube.webp?v=1741630837"},{"product_id":"western-electric-300b","title":"Western Electric 300B Vacuum Tube","description":"\u003ch1\u003eWestern Electric 300B Power Tube\u003c\/h1\u003e\n\u003ch3\u003eA truly natural-sounding triode made in a modern facility in America.\u003c\/h3\u003e\n\u003cp\u003eWestern Electric revived production of the 300B in 1997, and in 2017 moved to a modern facility where they produce this legendary triode whose use dates back to the early years of telecommunication.\u003c\/p\u003e\n\u003cp\u003eThe WE 300B is a piece of great audio history that's still utterly relevant because of its wonderful sound, but also now because of modern manufacturing that assures close tolerances and great consistency. All tubes are factory tested and matched by Western Electric.\u003c\/p\u003e\n\u003cp\u003eThe sound is balanced, powerful, and refined with quality bass from the lowest registers up. The midrange is truly a thing of beauty with tremendous presence. High frequencies are transparent, sweet, and, in Western Electric's words, \"burnished and beautifully seductive.\"\u003c\/p\u003e\n\u003cp\u003eThis 300B offers extraordinary air and space between performers, and the quiet, focused soundstage has immense width and depth. \u003c\/p\u003e\n\u003cp\u003eThe air and space between performers are extraordinary, performers appear on a quiet and focused soundstage whose width and depth are masterfully rendered. You don’t have to search to find the sweet spot with a WE 300B amplifier, it’s all around you.\u003cbr\u003e\u003cbr\u003eFind out what tube aficionados all over the globe know, the WE 300B is the most natural, elegant, and emotive triode anywhere.\u003c\/p\u003e\n\u003ch4\u003eAbout Western Electric\u003c\/h4\u003e\n\u003cp\u003eFounded in 1869, Western Electric's history is intertwined with the history of transmitted and recorded sound. An American brand through and through, it was owned by AT\u0026amp;T until it was bought and revived in 1996 by entrepreneur Charles G. Whitener of Westrex Corporation. The goal was to manufacture vacuum tubes and high-fidelity audio equipment.\u003c\/p\u003e\n\u003cp\u003eIn 1997, a newly created run of Western Electric 300B tubes began shipping worldwide, to great excitement among the tube audio community. In 2017, a modern tube manufacturing operation was set up in Rossville, Georgia with the goal of modernizing 300B manufacturing, adding additional tube lines, and house research and design of new products under this proud revival of an original American brand.\u003c\/p\u003e\n\u003ch3\u003eCharacteristics\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eEf, Eb, Ec:\u003c\/strong\u003e 5 V AC, 300V, -61 V\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003ePlate Current:\u003c\/strong\u003e 60 milliamp\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eAmplification Factor:\u003c\/strong\u003e 3.85\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlate Resistance:\u003c\/strong\u003e 700 Ohm\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eGrid to Plate Transconductance:\u003c\/strong\u003e 5500 micromhos\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003eMaximum Plate Voltage:\u003c\/strong\u003e 450 V\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaximum Plate Dissipation:\u003c\/strong\u003e 40 W\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaximum Plate Current for Average Tube (Fixed grid bias, Adjustable bias):\u003c\/strong\u003e 70 milliamp, 100 milliamp\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Western Electric","offers":[{"title":"Matched Pair","offer_id":41952541737144,"sku":"WE-300B-2","price":1499.0,"currency_code":"USD","in_stock":true},{"title":"Matched Quad","offer_id":41952541769912,"sku":"WE-300B-4","price":3099.0,"currency_code":"USD","in_stock":true},{"title":"Single Tube","offer_id":41952541704376,"sku":"WE-300B-1","price":699.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/products\/WEbox.jpg?v=1741630539"},{"product_id":"ram-labs-super-low-noise-ge-5751","title":"RAM Labs Super Low Noise GE 5751","description":"\u003ch1\u003eRAM Labs Super Low Noise GE 5751\u003c\/h1\u003e\n\u003ch3\u003eComputer-graded to within 1 dB of the tube’s theoretical noise limit for phonostages and other critical low-level applications. A buy-out from the legendary RAM Labs\u003c\/h3\u003e\n\u003cp\u003eThe GE 5751 is a nine-pin, high-mu dual triode developed for dependable voltage-amplifier service. Each triode section has its own cathode connection, while the center-tapped heater allows operation from either a 6.3 V or 12.6 V supply. GE’s original design emphasizes sturdy, vibration-resistant construction and reliable operation under demanding conditions.\u003c\/p\u003e\n\u003cp\u003eWith a nominal amplification factor of 70, the 5751 provides less gain than a 12AX7, which is typically rated at 100. It shares the familiar 12AX7-family pin configuration but has different electrical characteristics. In equipment designed or approved for it, the 5751 can reduce overall stage gain while retaining the high-mu dual-triode architecture used in many preamplifier circuits.\u003c\/p\u003e\n\u003cp\u003eCompatibility should always be confirmed with the equipment manufacturer. A 5751 should not be treated as a universal replacement for every 12AX7 application.\u003c\/p\u003e\n\u003ch4\u003eRAM Labs Super Low Noise Selection\u003c\/h4\u003e\n\u003cp\u003eRAM Labs’ Super Low Noise grade is selected to measure within 1 dB of the theoretical noise limit for the tube. This is RAM Labs’ most stringent published dual-triode noise grade and is intended for phonostages and other critical low-level applications in which even a very small amount of tube noise can become audible after substantial amplification.\u003c\/p\u003e\n\u003cp\u003eEvery dual triode is tested and graded using RAM Labs’ proprietary computer-based system. Measurements are taken separately for both sections, with the results recorded on the tube box. These include noise voltage over a bandwidth of 400 Hz to 20 kHz, RAM Labs’ proprietary RAM Factor, susceptibility to microphonics, AC gain at 1 kHz, and a DC plate value used to identify operating variations.\u003c\/p\u003e\n\u003cp\u003eThe Low Noise and Super Low Noise versions are the same GE 5751 tube type, but they pass different selection thresholds. Low Noise tubes measure within 4 dB of the theoretical noise limit, while Super Low Noise tubes must measure within just 1 dB. Both grades are also evaluated for microphonics, gain, and operating variation; the published numerical distinction between them is the tighter noise requirement.\u003c\/p\u003e\n\u003ch4\u003eAbout RAM Labs\u003c\/h4\u003e\n\u003cp\u003eRoger A. Modjeski founded RAM Labs in 1981 after working as a design consultant and chief engineer for Harold Beveridge Inc. Modjeski was known both for his Music Reference amplifiers and preamplifiers and for his extensive research into the measurement, selection, and application of vacuum tubes.\u003c\/p\u003e\n\u003cp\u003eAt RAM Labs, Modjeski developed a computer-based signal-tube tester using proprietary software originally written for an Apple II computer. He later expanded the system to test power tubes, establishing methods for evaluating both bias and transconductance under relevant operating conditions. RAM Tubes continues to use his research and testing principles following his death in 2019.\u003c\/p\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eVintage GE-manufactured 5751 dual triode\u003c\/li\u003e\n\u003cli\u003eRAM Labs Super Low Noise grade\u003c\/li\u003e\n\u003cli\u003eSelected to within 1 dB of the theoretical noise limit\u003c\/li\u003e\n\u003cli\u003eRecommended for phonostages and other critical low-level applications\u003c\/li\u003e\n\u003cli\u003eComputer tested for noise, microphonics, gain, and operating variation\u003c\/li\u003e\n\u003cli\u003eSeparate test data recorded for both triode sections\u003c\/li\u003e\n\u003cli\u003eLower nominal gain than a 12AX7\u003c\/li\u003e\n\u003cli\u003eCenter-tapped heater for 6.3 V or 12.6 V operation\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003cp\u003e\u003cb\u003eManufacturer:\u003c\/b\u003e General Electric\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eTube Type:\u003c\/b\u003e 5751\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eConstruction:\u003c\/b\u003e High-mu dual triode with separate cathode connections\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eBase:\u003c\/b\u003e 9-pin miniature\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMounting Position:\u003c\/b\u003e Any\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eNoise Grade:\u003c\/b\u003e Super Low Noise (SLN)\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003ePublished Noise Selection:\u003c\/b\u003e Within 1 dB of the theoretical noise limit\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMeasured Parameters:\u003c\/b\u003e Noise voltage, RAM Factor, microphonics, AC gain, and DC plate value for each triode section\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eNoise Measurement Bandwidth:\u003c\/b\u003e 400 Hz–20 kHz\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eHeater Voltage:\u003c\/b\u003e 6.3 V parallel or 12.6 V series\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eHeater Current:\u003c\/b\u003e 350 mA parallel or 175 mA series\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eNominal Amplification Factor:\u003c\/b\u003e 70\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003ePlate Resistance:\u003c\/b\u003e 58,000 ohms\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eTransconductance:\u003c\/b\u003e 1,200 micromhos (1.2 mA\/V)\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMaximum Plate Voltage (Design Center):\u003c\/b\u003e 300 V\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMaximum Plate Dissipation (Each Section, Design Center):\u003c\/b\u003e 1 W\u003c\/p\u003e","brand":"Ram","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":53806219100344,"sku":"RAM-5751-SLN-P","price":119.0,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":53806219133112,"sku":"RAM-5751-SLN-P-C","price":127.0,"currency_code":"USD","in_stock":false},{"title":"Kevin's Stash \/ No Cryo","offer_id":53806219165880,"sku":"RAM-5751-SLN-KS","price":129.0,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":53806219198648,"sku":"RAM-5751-SLN-KS-C","price":137.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/files\/GE_5751_Tube_Thumbnailcopy_669f8a16-3516-4785-8d7a-9486c93d535b.jpg?v=1784940358"},{"product_id":"ram-labs-low-noise-tested-ge-5751","title":"RAM Labs Low Noise GE 5751","description":"\u003ch1\u003eRAM Labs Low Noise GE 5751\u003c\/h1\u003e\n\u003ch3\u003eComputer-graded to within 4 dB of the tube’s theoretical noise limit for quiet performance in high-quality line stages. A buy-out from the legendary RAM Labs\u003c\/h3\u003e\n\u003cp\u003eThe GE 5751 is a nine-pin, high-mu dual triode developed for dependable voltage-amplifier service. Each triode section has its own cathode connection, while the center-tapped heater allows operation from either a 6.3 V or 12.6 V supply. GE’s original design emphasizes sturdy, vibration-resistant construction and reliable operation under demanding conditions.\u003c\/p\u003e\n\u003cp\u003eWith a nominal amplification factor of 70, the 5751 provides less gain than a 12AX7, which is typically rated at 100. It shares the familiar 12AX7-family pin configuration but has different electrical characteristics. In equipment designed or approved for it, the 5751 can reduce overall stage gain while retaining the high-mu dual-triode architecture used in many preamplifier circuits.\u003c\/p\u003e\n\u003cp\u003eCompatibility should always be confirmed with the equipment manufacturer. A 5751 should not be treated as a universal replacement for every 12AX7 application.\u003c\/p\u003e\n\u003ch4\u003eRAM Labs Low Noise Selection\u003c\/h4\u003e\n\u003cp\u003eRAM Labs’ Low Noise grade is selected to measure within 4 dB of the theoretical noise limit for the tube. RAM identifies this grade as particularly suitable for high-quality line stages and other applications in which low noise is important but the exceptionally stringent selection required for a high-gain phonostage may not be necessary.\u003c\/p\u003e\n\u003cp\u003eEvery dual triode is tested and graded using RAM Labs’ proprietary computer-based system. Measurements are taken separately for both sections, with the results recorded on the tube box. These include noise voltage over a bandwidth of 400 Hz to 20 kHz, RAM Labs’ proprietary RAM Factor, susceptibility to microphonics, AC gain at 1 kHz, and a DC plate value used to identify operating variations.\u003c\/p\u003e\n\u003cp\u003eThe published distinction between the Low Noise and Super Low Noise versions is the measured noise threshold. The underlying tube type remains the same, but the Super Low Noise grade must meet a substantially tighter selection standard.\u003c\/p\u003e\n\u003ch4\u003eAbout RAM Labs\u003c\/h4\u003e\n\u003cp\u003eRoger A. Modjeski founded RAM Labs in 1981 after working as a design consultant and chief engineer for Harold Beveridge Inc. Modjeski was known both for his Music Reference amplifiers and preamplifiers and for his extensive research into the measurement, selection, and application of vacuum tubes.\u003c\/p\u003e\n\u003cp\u003eAt RAM Labs, Modjeski developed a computer-based signal-tube tester using proprietary software originally written for an Apple II computer. He later expanded the system to test power tubes, establishing methods for evaluating both bias and transconductance under relevant operating conditions. RAM Tubes continues to use his research and testing principles following his death in 2019.\u003c\/p\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eVintage GE-manufactured 5751 dual triode\u003c\/li\u003e\n\u003cli\u003eRAM Labs Low Noise grade\u003c\/li\u003e\n\u003cli\u003eSelected to within 4 dB of the theoretical noise limit\u003c\/li\u003e\n\u003cli\u003eRecommended for high-quality line stages and other noise-sensitive applications\u003c\/li\u003e\n\u003cli\u003eComputer tested for noise, microphonics, gain, and operating variation\u003c\/li\u003e\n\u003cli\u003eSeparate test data recorded for both triode sections\u003c\/li\u003e\n\u003cli\u003eLower nominal gain than a 12AX7\u003c\/li\u003e\n\u003cli\u003eCenter-tapped heater for 6.3 V or 12.6 V operation\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003cp\u003e\u003cb\u003eManufacturer:\u003c\/b\u003e General Electric\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eTube Type:\u003c\/b\u003e 5751\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eConstruction:\u003c\/b\u003e High-mu dual triode with separate cathode connections\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eBase:\u003c\/b\u003e 9-pin miniature\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMounting Position:\u003c\/b\u003e Any\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eNoise Grade:\u003c\/b\u003e Low Noise (LN)\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003ePublished Noise Selection:\u003c\/b\u003e Within 4 dB of the theoretical noise limit\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMeasured Parameters:\u003c\/b\u003e Noise voltage, RAM Factor, microphonics, AC gain, and DC plate value for each triode section\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eNoise Measurement Bandwidth:\u003c\/b\u003e 400 Hz–20 kHz\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eHeater Voltage:\u003c\/b\u003e 6.3 V parallel or 12.6 V series\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eHeater Current:\u003c\/b\u003e 350 mA parallel or 175 mA series\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eNominal Amplification Factor:\u003c\/b\u003e 70\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003ePlate Resistance:\u003c\/b\u003e 58,000 ohms\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eTransconductance:\u003c\/b\u003e 1,200 micromhos (1.2 mA\/V)\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMaximum Plate Voltage (Design Center):\u003c\/b\u003e 300 V\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMaximum Plate Dissipation (Each Section, Design Center):\u003c\/b\u003e 1 W\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"RAM","offers":[{"title":"Platinum Grade \/ No Cryo","offer_id":53806219264184,"sku":"RAM-5751-P","price":99.0,"currency_code":"USD","in_stock":true},{"title":"Platinum Grade \/ Yes Cryo","offer_id":53806219296952,"sku":"RAM-5751-P-C","price":99.0,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ No Cryo","offer_id":53806219329720,"sku":"RAM-5751-KS","price":109.0,"currency_code":"USD","in_stock":true},{"title":"Kevin's Stash \/ Yes Cryo","offer_id":53806219362488,"sku":"RAM-5751-KS-C","price":109.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1564\/1247\/files\/GE_5751_Tube_Thumbnailcopy.jpg?v=1784940344"}],"url":"https:\/\/upscaleaudio.pro\/collections\/vacuum-tubes.oembed","provider":"Upscale Audio","version":"1.0","type":"link"}