2x Mullard ECC83 Valves. This valve has also been tested in amplifier without any noise. NOS specification: Ia = 1.2(mA), gm = 1.6(mA/V). Ia2 = 1.3(mA), gm2 = 1.6(mA/V). Ia1 = 1.6(mA), gm1 = 1.7(mA/V).
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