psevdonim said:how does the 741 in this schematics https://www.electronics-lab.com/projects/audio/041/index.html work ?
If R10 would go to pin 6 of 741, I'd understand it. But here the C2 interrupts the connection.
TheVictim said:The circuit has complexity that just isn't needed. There is no reason to use darlington pairs in a push-pull here anymore. Even if you still used the 741 you can use a single supply voltage biasing the non-inverting input with 1/2Vcc, then use a power amp like a 386 (or something with a bit more performance, but it is a good match for the venerable 741).
TheVictim said:Digging through my junkbox I found a STK439. Quite dated, but it will deliver the necessary output, and in stereo, in one package.
No, it sounds fine (except for the poor quality from the 1458 dual 741 opamp).Hero999 said:Even with your modification it will still sound crap.
psevdonim said:I can't quite agree with the function of C2, because it's 5600pF, so it has little effect to audio range, and it's connected more to the speaker rather than to output transistors.
This schematics is about 25 years old. Does anyone know, who the original constructor is and where was it published for the first time ?
TheVictim said:When making impedance calculations for circuits using darlingtons, do you multiply the gain of each stage within the darlington together, or is another method used?