Tester 12AX7 Expected Gain (Mu) value = 92. 12AX7 tubes have a center design target of 1600Gm. TESTED ON A MAXI PREAMP II TUBE TESTER FOR GAIN(Mu), TRANSCONDUCTANCE(Gm) AND NOISE(dB). Tester Noise (dB) Range -92dB - 0dB.
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