[Boatanchors] Heathkit GR-78 Receiver - Audio

[Mark Johnson]

Team;
 
Playing with a GR 78 portable SW receiver. I installed a newer style Nicad and Zener Diode to hold voltages around the 9.6VDC mark.....Receiver works fine but the audio output sounds slightly distorated to me. Voltage checking reveals around 7 VDC on the base(s) of each Audio output transistor. According to the doc, it should be around 4.6VDC. I can't get the voltages down to spec; assuming thats the cause of my slight distoration. Audio coming from the detector stage, (before the audio amp) through my Heath Signal Tracer seems to be fine. 
 
I know the audio amp was designed for communications quality audio but it's not quite right to me. I hate to admit I've done a little "shot gunning" with new parts in the audio amp; always a last resort, but no change. The question for the group is, am I trying to fix somehting that is working to spec? The audio is the same out of headphones and speaker. There is just the slightest distoration when listening to AM Broadcast. 
 
Thanks.
 
Mark V Johnson VE3DJU/VE3LU