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Professionally Tested and Matched Pair of General Electric (GE) JAN 5654W Vacuum Tubes.  6AK5, 6AK5W, EF95, 6J1, 6J1P Replacement

The mil-spec General Electric (GE) JAN 5654W was originally designed as a 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. This great sounding vintage tube has found new life as a premium replacement for 6J1, 6J1P, 6AK5 and EF95 tubes used in headphone and other audio amplifiers and is often used by amplifier designer's and tube roller's looking for improved sound quality. At Riverstone Audio, we personally inspect, test and pair these vacuum tubes for both plate current and mutual conductance.  As a final step, prior to shipping, all tube sets are also subjected to an audio test in a preamplifier.
Only the best tubes are selected by Riverstone Audio for use as matched pairs. All 5654 vacuum tubes sold by Riverstone Audio are precision-matched using state-of-the-art Amplitrex AT1000 digital testers.  We currently have an inventory of over 75,000 NOS GE JAN 5654W vacuum tubes - all still in their original factory-sealed cartons and with the manufacture dates that we have found provide the best quality 5654 tubes for high fidelity audio applications.  With an inventory this large, we are able to select the best tubes for our use in our matched pairs and quads. 

Riverstone Audio's Tube Testing Facility

Best Sounding Vintage Audio Tubes


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Start From A State of The Art Vacuum Tube Testing Facility

Riverstone Audio specializes in the testing of vintage US and Russian vacuum tubes used for audio applications. During the past decade, Riverstone Audio has tested over 70,000 vintage vacuum tubes. The proper evaluation of vintage tubes for audio applications requires considerable effort and specialized test equipment. Our workshop has the best available equipment for testing and evaluating the electrical and audio qualities of vacuum tubes, including several state-of-the-art Amplitrex AT1000 tube testers and various vintage and custom-built tube and audio test equipment. The Amplitrex tube testers allow us to determine a vacuum tubes electrical parameters with precision, including plate current, mutual conductance, grid characteristics, gas, life, inter-element leakage and noise. Additional test equipment allow us to evaluate vacuum tubes under different test parameters, including self-bias (cathode bias) test modes. Riverstone Audio personnel are trained professionals, with a detailed understanding of vacuum tube technology and amplifiers. We have the hands-on experience needed to select vintage vacuum tubes that will provide the best possible audio listening experience. Our senior engineers are experienced in running engineering research labs and closely monitor all aspects of testing, matching, and QC procedures and are also available to answer customer questions when they arise.


Our experienced technicians and engineers throughly test, select and match the best tube pairs for audio performances so you don't need to, by trial and error.


 Electrical parameter testing is performed 

 using Amplitrex AT1000 tube testers.


  • All 5654W tubes are fully tested for important electrical parameters, including plate current (ia), mutual conductance (Gm), grid voltage (or grid current depending on test mode), inter-element leakage, gas, noise and life.

  • Tubes are matched within 3% for BOTH Gm and plate current.

  • Matched pairs undergo a final audio test.


 Clearly Indicated Test Results

  • WE PROVIDE TEST RESULTS DIRECTLY ON TUBE BOXES - measured values for ia and Gm are attached to the tube boxes.

  • The data labels are Riverstone Audio’s quality promise to our customers.


We reject 50% to 60% of the vintage NOS tubes we test.

Why such a high reject rate? It will become clear as you scroll down and read on.  You will see how many tests and quality control steps a tube need to go through to pass our quality standards and to be matched for sale.

With our high standards, only fewer than 40% of the NOS 5654W tubes we test can be considered to use in audio amplifiers and are selected for Riverstone Audio's specifically matched tube pairs. We want to find tubes that provide detailed sound quality, low noise and long trouble-free operation. We use standards that are more strict than manufacture's specified NOS standards and match them within tight errors to meet the requirements for audio applications. We also test and reject tubes based on parameters that other sellers may not have the equipment and capacity to test. We have confidence that 5654W tubes sold by Riverstone Audio are most rigorously tested and matched tubes in the audio vacuum tube industry.



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