• Riverstone Audio - Tested/Matched Pair (2 Tubes) 7-Pin GE JAN 5654W Fully-Tested Vacuum Tubes - Upgrade for 6AK5 / 6J1 / 6J1P / EF95 - GE 5654W Platinum Grade Pair

    A very closely matched pair (2 tubes) of vintage US-manufactured GE JAN 5654W vacuum tubes. All tubes are Amplitrex TESTED and MATCHED. Both plate current and Gm are matched to within 3%. We subject these tubes to multiple test cycles and plate voltages to determine stability. In addition to ip, Gm, leakage/gas, noise and life testing, the matched tubes undergo a final audio sound check to make certain they are indeed audio quality. Tubes that show the slightest abnormality are rejected. With our high standards, less than 50% of the NOS 5654W tubes we test are considered for use in these special matched sets. 5654W tubes were originally designed as a low noise premium-grade substitute for 6AK5 and EF95 vacuum tubes. The "W" designation refers to ruggedized, military grade, tubes; better quality control and internal design changes to enhance reliability and minimize microphonics/noise. This great sounding vintage tube has found new life as a replacement for 7-pin 6J1, 6J1P (6ZH1P-EV), 6AK5 and EF95 tubes and are commonly used by audiophiles looking for improved sound quality. All tubes selected for our tested/matched pairs will have identical date codes and are guaranteed to test at NOS levels of 5000 micro-mho or higher and a plate current (ip) of 7.2 mA or higher. (Tested in fix...

    • Brand: Riverstone Audio
    • ASIN: B01BFJDTW0
    • UPC: 763769918220

  • Riverstone Audio - Matched Pair (2 Tubes) 6N6P (6Н6П) NOS Vacuum Tubes - NEVZ (Novosibirsk, Russia) - Amplitrex Tested and Matched, Platinum Grade Pair - NOS 6N6P (2 Tubes)

    Tested AND Matched Pair 6N6P (6Н6П) vacuum tubes manufactured by NEVZ (Novosibirsk, Soviet Union). The 6N6P tubes we select for our Platinum Grade pairs are the most thoroughly tested vacuum tubes available anywhere. To determine stability, tubes are subjected to multiple test cycles. The typical test duration (not including tube burn-in) is 15 minutes. Tubes are matched within 10% for plate both current (ip) and mutual conductance (Gm) and within 5% for tube gain. As a final quality check, all matched tubes are auditioned in an amplifier to determine sound quality. We have confidence in the quality of the tubes we select and back them with a no-nonsense one-year money-back warranty. We also guarantee that the tubes will test at NOS levels when received. ***Please Note: To the best of our knowledge, all 6N6P tubes we use in our Platinum Grade sets are NOS tubes. The mark "CCCP" on the glass envelope of the tubes denotes export from USSR (the CCCP mark was not used after 1991).*** To protect the tubes during shipping and storage they are are supplied in Riverstone Audio's custom "Tube Cradle" boxes.

    • Color: NOS 6N6P Matched Pair
    • Brand: Riverstone Audio
    • ASIN: B07HNXMVH8

  • Riverstone Audio, 6N3P-E Matched Pair (2 tubes) - Vintage NOS Russian Vacuum Tubes Replacement for 6N3 / 6N3P / 5670 / 5670W / 396A / 2C51 - Amplitrex Tested/Matched - Platinum Grade Pair (6N3P-E)

    Our Platinum Grade vacuum tubes are the most thoroughly tested 6N3P-E tubes available. To determine stability, tubes are subjected to multiple test cycles and are matched within 6% for mutual conductance (Gm) and within 5% for tube gain (final testing of these tubes is performed under auto-bias at a fixed plate current ip = 8.8 mA). All matched tubes are auditioned in an amplifier to determine sound quality. FEWER THAN 35% of the 6N3P-E tubes we test meet our high standards for audio use and are chosen for Platinum Grade pairs - we select tubes that show stability during multiple test cycles and exhibit low noise and excellent audio sound during final testing in an audio amplifier. You will not find a more rigorously tested pair of vacuum tubes anywhere. The 6N3P-E tube is the high reliability version ("E" suffix in the tube code) and is a great upgrade for Chinese 6N3 tubes. ***Please Note: We carefully inspect all tubes we use and to the best of our knowledge the 6N3P-E tubes we use in our Platinum Grade sets are NOS tubes. We also guarantee that the tubes will test at NOS levels when received.*** To protect the tubes during shipping and storage, the tubes are supplied in Riverstone Audio's custom "tube cradle" boxes. As a US seller we have confidence in the quality of what we ...

    • Color: 6N3P-E
    • Brand: Riverstone Audio
    • ASIN: B07J671QV3

  • Tung-Sol 12AX7 Preamp Vacuum Tube, Single

    Premium high gain Twin Triode with ultra-low microphonic. Improved reissue of the Vintage NOS Tung Sol 12AX7

    • Brand: Unknown
    • ASIN: B0018SJLFS
    • UPC: 723175698451

  • Riverstone Audio - Matched Pair (2 Tubes) 9-Pin GE NOS/NIB JAN 5670W Fully-Tested Vacuum Tubes 6N3, 6N3P, 2C51 5670 396A Tube Upgrade/Replacement - 5670W Platinum Grade Pair

    A pair (2 tubes) of closely matched mil-spec 9-Pin GE JAN 5670W vacuum tubes. These platinum grade tubes have undergone detailed testing and audio testing. The vintage NOS GE 5670W tubes were obtained from factory sealed boxes and are a low-noise replacement for 2C51 and other 5670 tubes. 5670W tubes are also often used as a replacement for 6N3 and 6N3P vacuum tubes (the glass envelope of the GE 5670W tube is approx. 5 mm shorter than 6N3 and 6N3P tubes). The "W" designation in the 5670W tube number refers to ruggedized, military grade tubes; better quality control and internal design changes to enhance reliability. We test/match all 5670W vacuum tubes using Amplitrex AT1000 tube testers. Testing is performed using auto-bias mode (plate voltage is fixed at 150 V and plate current at 8.2 mA); grid voltage is measured to determine deviation from expected NOS level. Vp versus ip curves are also examined to determine balance between tube sections and overall tube performance (Vp-ip curves are generated under fixed-bias mode). Additional quality checks include shorts/leakage, gas, noise and a life test. These vacuum tubes are well balanced between tube sections. All tubes in our matched tube sets are guaranteed to test at NOS (new old stock) levels. Tube boxes are clearly labeled with...

    • Brand: Riverstone Audio
    • ASIN: B01DLBABE4
    • UPC: 605945647312

  • Tube Amp Doctor 6V6GT-STR Premium Selected Vacuum Tube, Matched Quad

    This all new TAD 6V6GT-STR combines the exceptionally sweet voiced NOS 6V6GT like the RCA or GE 6V6GTY with up to date demand to withstand the higher operating voltages due to raised AC supply.Surprisingly tight bass which you would not expect except with the very best choice of real NOS 6V6GT treasures.TAD recommends the TAD 6V6GT-STR for all 6V6 applications where a powerful but sweet tone is desired; Works great in Single Ended Class A Amps like the Fender -Tweed- Champ, Vibro-Champ, Fender Champion 600 or the Univalve. Also perfect choice for Reverb Driver in Vibrokings and Dual Professionals.Available in Singles, Matched Pairs or Matched Quads

    • Color: Matched Quad
    • Brand: Tube Amp Doctor
    • ASIN: B005LS3K4E
    • UPC: 609722132145

  • Riverstone Audio - 6J9P-E (6Ж9ПE / 6zh9P-E) Matched Pair (2 tubes) - Vintage Russian Vacuum Tubes - Amplitrex Tested - Replacement for 6J9, E180F, 6688 Tubes - Platinum Grade - NOS (2 Tubes) 6J9P-E

    Tested AND Matched pair of 6J9P-E (6Ж9ПE / 6zh9P-E) NOS Vacuum Tubes. Our Platinum Grade 6J9P-E vacuum tubes are an excellent replacement for the 9-pin Chinese 6J9 tubes used in a variety of audio circuits. You will not find a more rigorously tested pair of vacuum tubes anywhere. To determine stability, all tubes are subjected to multiple test cycles and are matched within 6% for plate current (ip) and mutual conductance (Gm). All matched tubes are auditioned in an amplifier to determine sound quality. Fewer than 40% of the 6J9P-E tubes we test meet our high standards for audio use and are chosen for Platinum Grade pairs - we select tubes that show stability during multiple test cycles. These tubes are also selected for low noise and for audio sound quality during final evaluation of the matched pairs in an audio amplifier. ***Please Note: To the best of our knowledge, the 6J9-E tubes we use in our Platinum Grade sets are NOS tubes.*** We guarantee that the tubes will test at NOS levels when received and back them with a no-nonsense ONE YEAR money-back warranty - THE BEST WARRANTY available in the audio tube business. To protect the tubes during shipping and storage, the tubes are supplied in Riverstone Audio's custom "tube cradle" boxes.

    • Color: Mil Spec. Version
    • Brand: Riverstone Audio
    • ASIN: B07JLYD1HG

  • Russian Vacuum Tube Valve 6N2P (ECC83 12AX7) 6V Heater NOS (4pcs)

    This vacuum tube has been tested at the factory shipment. It is an old stock item of military model manufactured in the former Soviet era from 1970 to 1990 's. Since the picture shows the average thing of stock, it may differ slightly from the actual one. (Printing, plate features, etc.) There is no guarantee of matched even in the case of exhibition with two or more sets. There are not individual boxes for military stock items. Please acknowledge it beforehand.

    • Brand: Generic
    • ASIN: B0794D3NQX

  • Russian Vacuum Tube Valve 6J9P-E (E180F 6688) NOS (2pcs)

    This vacuum tube has been tested at the factory shipment. It is an old stock item of military model manufactured in the former Soviet era from 1970 to 1990 's. Since the picture shows the average thing of stock, it may differ slightly from the actual one. (Printing, plate features, etc.) There is no guarantee of matched even in the case of exhibition with two or more sets. There are not individual boxes for military stock items. Please acknowledge it beforehand.

    • Brand: Generic
    • ASIN: B0794CGN9Y

  • Russian Vacuum Tube Valve 6N1P (6DJ8 ECC88 6922) NOS (2pcs)

    This vacuum tube has been tested at the factory shipment. It is an old stock item of military model manufactured in the former Soviet era from 1970 to 1990 's. Since the picture shows the average thing of stock, it may differ slightly from the actual one. (Printing, plate features, etc.) There is no guarantee of matched even in the case of exhibition with two or more sets. There are not individual boxes for military stock items. Please acknowledge it beforehand.

    • Brand: Generic
    • ASIN: B0794FC1ZM