Questions regarding stability networks

[EL34Dave]

That looks rather like "If I don't understand it then that is because you didn't explain it properly". I'm sure you didn't mean to say this.

No, that wasn't my intent. I’m sure you and I have experienced people who excel at explaining complex technical topics very clearly and succinctly, as well as others who are mainly interested in showing how smart they are. I learn much better from the former.

To understand feedback you first have to understand complex numbers; without that you cannot understand, however perfectly someone explains it to you. Ideally you would also know some complex analysis too, as some aspects of feedback theory are counter-intuitive to those who are baffled by poles and zeros in the complex plane and would not know an analytic function if one dropped on their foot. Fortunately, it is possible to make some progress in using feedback without understanding it.

Again, I am not an electronics engineer, nor do I have the time or inclination to go there. I am not designing a circuit from scratch, just tweaking (for the fun of it) an already good variant of the ST-70. I’ve read elsewhere that it can be improved by tuning the stability networks for the best square wave performance. Will the amp sound any better? Who knows. I probably couldn’t tell the difference anyway.

 

[DF96]

Best sound may or may not coincide with best square wave. However, poor sound may accompany very poor square wave, which may be why people use square wave as a criterion. It is an easy test to do; people do what they can.