Matched pair. These are triode section by TAD matched for Gm and then matched for pairs on an Amplitrex AT-1000. Here are the virtues of JJ ECC83 MG tubes - This tube will be a classic JJ is a mainstay in the Vacuum Tube industry.
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I test all tubes thoroughly and with great care. I test to the best of my ability, and I report all results honestly.
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AMPEREX ECC83 12AX7 B O G E Y S . LEGENDARY ' TREBLE CLEF'. BUGLE BOYS. MATCHED SET. Closely Matched Codes: IO4 223 IO4 137. These are the Real Deal . ★ Honesty, Reliability and Integrity are Everything ★.
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Construction: short gray plate ring getter copper rods. Tested at: 71/79 plate current 7.9/8.2. The minimum is equal to 65% of the life of the tube. Glass: clear. Tested for shorts and gas. Date codes 912 0-26.
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ECC83 12AX7 Valve Tube. Long Black Plates, Square Getter. RCA, Made in USA. Used, Supplied in Original Box.
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Here's a NOS sleeve of Amperex W. Germany 12AX7A/ECC83 tubes. Made in 1982. On my B&K 747 Gm tester where results are read in percent of new Gm value 0-120%, they test as follows: 110-110, 108-108, 102-120, 118-117, 100-100.
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Sections are matched for gm to 10%. The Tung-Sol ECC803S 12AX7A has high gain, ultra low microphonics and superb linearity. The sound of this tube is full and musical.
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Triple Platinum Matched on Amplitrex AT1000. Amplitrex AT1000 Test Results 95%+ GM = Within NOS Specs 90%+ EM = Within NOS Specs. All tubes are tested with the Audiophile in mind for SHORTS, GAS, MUTUAL CONDUCTANCE and NOISE (large tube lots are not tested for noise).
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