Tiny, Simple Amp

Hi,

There are loads of DIY circuits on the internet. I was wondering if someone could recommend one for me, which is as simple as they come, easy to put on a PCB, and well documented.

The sound quality doesn't have to be amazing. It only have to be powerful enough to turn a line level audio signal into a signal to drive a 5cm speaker.

Any advice or input would be much appreciated,

James

You can try an LM386. They're cheap and easy.

https://www.electro-tech-online.com/custompdfs/2011/01/LM386.pdf

Lots of info on the web about them too.

Use LM386 monoblock amplifier as search terms for Google.
You will find plenty of websites that have full schematics parts lists and wiring informtion for simple perfboard setups. They're great little single channel amps. Want stereo? Build two Build four and you can bridge them. Don't be cheap on power supply and power supply filtering that'll probably have the greatest influence on quality.

I would use a TDA2822M.
It has the same 8-pins case as an LM386 amp but provides 1.1W at clipping into an 8 ohms speaker with a 6V supply (4 AA or AAA cells).
The LM386 provides only 0.45W into an 8 ohms speaker at clipping with a 9V supply. The 9V battery will not last long.

The LM386 needs a huge output capacitor but the TDA2822M is bridged so doesn't use an output capacitor.

Tiny 2.25" speakers sound awful.