I have had another look at the feedback issue, this time with more sensible eyes.
In my previous tests I made a mistake, I was not just disconnecting the feedback, I was disconnecting C19 the 100uf bypass capacitor in the emitter circuit of TX3, that was the reason it went from loud to quiet.
If I just disconnect R25, 22k, from the speaker then there is a slight increase in volume and it sounds a little fuller tone. So I guess I was wrong and it is negative feedback after all.
Mike
In my previous tests I made a mistake, I was not just disconnecting the feedback, I was disconnecting C19 the 100uf bypass capacitor in the emitter circuit of TX3, that was the reason it went from loud to quiet.
If I just disconnect R25, 22k, from the speaker then there is a slight increase in volume and it sounds a little fuller tone. So I guess I was wrong and it is negative feedback after all.
Mike
