Suggestions for cheap "bench amp"?

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Thanks for the info on the connector. Any advantage to using that over just plugging in RCAs?
It would be great if I knew how to find or read a data sheet. lol
I'm not that advanced yet, I think I need that simple chart. I'm just curious what general output I should expect from my 20v/3A power brick driving 4/8/16 ohm loads.
 
Ok, progress!
I got my enclosure designed and cut, and for the most part I'm very happy with it. I'll likely make a few tweaks and cut another one to adjust some hole positions and such, but this one should be fine for testing purposes.
This morning I rigged up everything temporarily just to make sure the board was working properly, and it is, except that I'm getting some pretty noticeable noise through the speaker with no input. I'm not sure of the correct terminology, but I'd call it 'background hiss' or maybe white noise. It's not super loud, but it's definitely there when there's no signal input. Oddly, if I turn the amp all the way up to full power, the noise disappears completely.
Is this typical of these types of chip amps, or is there something wrong with this board?
I'm powering it from a variable voltage power brick. I've tried it at everything from 12v to 24v, with no perceived difference in the background noise, or volume during audio playback, which I find a little odd.
I've tried a different power brick, and that one didn't work at all, but I suspect a faulty PSU there.
Any thoughts?
 

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Yes, Project 186 is a good bench amp and Rod details it well. I use one with 25V rails and it's more than adequate and super quiet.

Project 186

BTW, almost all the TPA3116 modules I've tried have hiss or other noises.

I'd also recommend Rod's project 186---his stuff WORKS, sounds good, and won't cost an arm and a leg!

I'll also throw my endorsement in here. Rod's stuff is quality and I like supporting his site with my dollar. Not many have provided more knowledge to the community than Rod.

Project 186 uses the boards and circuit from project 19.
Single Chip 50W Stereo Amplifier
 
Hi all,
Thanks for the input, but Rod's stuff looks far beyond my skills at this point.
I think I'll stick with my current amp and live with the noise. It's not too bad, I was just wondering if it was typical (seems it is) or if there was something wrong with this one that would require a return.
I'm very pleased that I received the version with the single, screwed down heatsink, and the can-style caps. Looks like a cleaner design all around.

I'm also quite happy with the way the enclosure turned out. I may even make a few tweaks for easier building, and offer these for sale somewhere as a complete, finished package.
I'm sure there are others like me who would like a simple 'pocket' testing amp, but who don't want to spend a fortune. I could probably sell the whole thing for about $35 plus postage, assembled and tested.
Anyone think that would be a viable product? Likely not here, since most everyone can roll their own, but maybe on eBay or locally.
 
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