2pcs TDA2822M DC 1.8-12V 2.0 Channel Stereo Amplifier Mini AUX Audio Amplifier Board Module AMP for Arduino

They work well as advertised. Structurally well made... Sound works good for what I need...i'm not using it to listen to music, and I havn't, so I dont know what music would sound like on it. Installation is easy.

First off, these are great! for those who are having noise issues, as is the case with these types of circuits, always use shielded cables for input signals, and definately use a clean (no "switching" noise) power supply... Any type of 'switching' power supply that does not have adequate filtering WILL put noise into the output!! as for what i am using these for... I make my own custom 'sound generator chambers', i which i use to calibrate precision microphones systems.... they are stable and work quite well for what i do, in my opinion... as for distrotion, matching the output impedances, and not 'overdriving' the input, solve that problem in most cases... my 5 cents :-)

These are functional. However volume and sound quality aren't very impressive compared to other products available for a similar cost. For experiments and projects where low fidelity and medium volume are acceptable these are functional. If you intend to use them for music I'd pay the few extra dollars.

Perfect for my application, sounded great!

Do these amplify? Yes. The problem is, they don't do very much unless your feed signal is already pretty loud, at which point it's a question of why bother. I don't know if the "5W" is split between both channels or per output but the output of these is terrible. The sound quality is "acceptable" (I didn't really have any issues with it but if you're looking for hifi then look elsewhere). I hooked mine up to a raspberry pi zero (GPIO witchcraft) through a filtering circuit and the results were less than stellar. It works and the audio is relatively clear but they just don't have the gusto to be worth using for the speakers i've got. Build quality is decent, connector blocks are excellent.

Great ! works well for the price you can;t beat it !

They amplify sound but are unusable due to how they pick up any little RF signals that may be present and amplify those too. I was only able to get a sort of clean sound by getting 30 feet away from my router. There was still a lot of hiss even then. You'd have to make a faraday cage enclosure to have any hope of using this anywhere other than the middle of nowhere.

Some electronics knowledge is helpful.