BowToEd wrote:
I breadboarded this circuit and now think I want to pursue a better design.
The circuit was laid out on an IC breadboard and powered by a 12v gel cell battery. The midpoint voltage between the two output transistors was a little low but nothing I couldn't design out. Other than semiconductor substitutions, the rest of the circuit was pretty much stock.
I listened to some PMJ featuring such talents as Haley Reinhart and the magnificent Robyn Adele Anderson. I noticed some fuzz that was slightly annoying to me and it could hardly pass for quality audio.
I'm not going to give up on this design yet. It's designed for a supply of 18 to 22 volts and I was using 12.9 via a battery. If I use a stronger power source, I should be able to realize at least one watt of power.
All in all, the thing makes noise in a speaker. I think I'll end up making a different design before building something permanent, though.
Ed
If the amp only produces a few watts I'll assume you will be using efficient speakers. 90db efficiency is usually enough. My 330mW 1920s tube amp plays loud on 99db efficient speakers.