Question

Any Electronic Nerds in here? Need help building Pocket Guitar Amp using one 741 opamp and one 386 opamp

Answer 1

Do you need help with the circuit?

Answer 2

I have a few different diagrams that I've tried... But I can't seem to get 15W while matching impedance... All I have are these two op amps, and I can't find any diagram incorporating both. Can I get 15W out of just one 386 or 741?

Answer 3

Have to admit, never thought of doing something like this. It may work with just one type of op-amp but I'm not sure.

I just found something really neat. It's a circuit that uses 2 386 op-amp. I'm not sure if you wanted to make your circuit from scratch but here's a link that may save you time:
http://www.runoffgroove.com/littlegem.html

I'd read up on the "Little Gem Mkll"

Answer 4

I am indeed building from scratch. Yeah, it's a wonder why you don't see them paired up...
And I will definitely read up on that.

Answer 5

Yes. What differentiates the 386 from the 741? Is one used for signals of a certain range of amplitudes?

Btw, what problem do you think would arise if one were to use one of each? Saturation?

Answer 6

I think the problem I have been having is impedance matching. I can get a pretty high output, but the speaker is clipping..

Answer 7

It may be due to an op-amp generating flicker noise; this happens when you have a high gain = high output.

Are you only using resistive impedances?

Answer 8

try this circuit

Answer 9

@linalynne @sugadev_lee I've just got the one speaker here, I'm not sure what you mean by resistive impedances.

Also, I don't have the 358 handy. I've only got one LM741 and one LM386. I've tried constructing high output amps out of both, with every config f trans/resist/cap I can think of.....

I was really hoping someone could help me invent the circuit. I realize the two amps are aimed at different applications, but I know we can get them to work together. And I'm not savvy enough with a data sheet to be able to imagine the answer here.

Answer 10

Resistive impedances as in you only have resistors in your circuit. (no capacitors...etc)
Btw, adding capacitors would help reduce noise, which you've said you had in your output (the speaker clipping).

Because I've never done something like this, I'd like to work with you to build a circuit that integrates both op-amps; it'll definitely be an interesting project!