2x MAZDA ECC83 Valves. NOS specification: Ia = 1.2(mA), gm = 1.6(mA/V). This valve has also been tested in amplifier without any noise. Ia1 = 1.45(mA), gm1 = 1.8(mA/V). Ia2 = 1.55(mA), gm2 = 1.75(mA/V).
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