Quote from: Littlewyan on November 15, 2013, 07:28:26 PM
Right we scoped the amp and there is no oscillation. Altho we did get it to oscillate a few times with no input and the volume turned up but that disappeared as soon as we plugged something into the input.
That leaves us with two possibilities. Either something in there is on the edge of instability - or you forgot to wire your input jacks as shown in the schematic, so that the inputs are grounded if nothing is plugged in.
Quote from: Littlewyan on November 15, 2013, 07:28:26 PM
We found The signal didnt distort until the PI output and then again a bit more on the Power Amp output.
That doesn't come as a surprise - the PI is just the second stage in this design, you'd need a really beefy booster to make your input stage distort...
I personally think you just have a minor leaddress issue - but check your input jacks first.
Toby