What I can tell you about the biasing of the output stages is that a fairly reputable company, Marantz, used some special diodes that tended to match the temperature/voltage drop properties of the output stage transistors. That was a quite non-trivial thing, getting all of the bias voltages to track so 6that the idling current would stay fairly constant. When those diodes fail then the output idling current goes way up and the whole thing gets very hot, and eventually fails. Then it becomes quite expensive to repair. Thus I would not suggest using an LED device to provide the bias voltage drop.It might work, or it might not.
To see some circuits that are a bit extreme with temperature compensation look at some automotive audio power amplifiers.

 

OK brain farts fixed, I hope.

 

What I can tell you about the biasing of the output stages is that a fairly reputable company, Marantz, used some special diodes that tended to match the temperature/voltage drop properties of the output stage transistors. That was a quite non-trivial thing, getting all of the bias voltages to track so 6that the idling current would stay fairly constant. When those diodes fail then the output idling current goes way up and the whole thing gets very hot, and eventually fails. Then it becomes quite expensive to repair. Thus I would not suggest using an LED device to provide the bias voltage drop.It might work, or it might not.
To see some circuits that are a bit extreme with temperature compensation look at some automotive audio power amplifiers.

Your reply was quite out of date for this thread the above post is my current thoughts on the subject.

 

Your reply was quite out of date for this thread the above post is my current thoughts on the subject.

That happens to me. I have still not mastered a lot of this website and forums. Sorry about that. But being out of date, or just far after the fact, is part of what happens with me sometimes. But the answers are still technically sound.

 

No problem, I'm just curious how well this works, if it does.