One of the nicest looking 1983 amps in silver and black eh? Liked to have kept this...
Nothing wrong really, bit noisy - caps etc. Subsonic buttons makes loud pop - cleaned pots/switches etc. Has a micro controlled preheat function:
54Vpp = 27Vp =- 19V RMS
P = V^2/ R = 19 x 19 / 8 ohm = 45W
All inputs work - tested the phono also at low phono level out - seems RIAA amp curve generates a bassier response than std ins?
The THD figures for no load resistor from Allan at w2aew YT site are:
Only 2nd harmonic dBc avg dV = -42.8 dB from the Fundamental, so...
10^ (-42.8/10) = 0.000052481
Sum of V2..V3... = 0.000052481
SQRT of 0.000052481 = 0.00724436
THD = 0.00724436 x 100% = 0.72 THD at volume 6 or approx 1/2 full volume distortion - but way more than the rated 1/2 power into 8 ohms of 0.003 ...?