I had problems installing this mod. I accidentally undersold and lost a couple of very small components while installing this. So now I have a GameBoy Advance SP without sound. Too many tricky solder points. Perhaps this mod could be redesigned to avoid undersold these microscopic components? I can't recommend this one unfortunately.

Works and makes the volume exponentially louder. However this mod is significantly more difficult to do, compared to some other mods, as you'll have to solder the ground of the amp to the very small end of a resistor. If you experience way more feedback than normal, check that ground point or solder a wire from the amp ground to the charge port or link ports ground and it should help clean up the audio.

Even with a good ground, you'll still have some feedback in which case, you should get a power cleaner mod which will help eliminate any remanence of buzzing or feedback!

It's a great mod, just takes time and some minor troubleshooting!

When installing this thing I had some trouble soldering to the tiny resistor. Aside from that it was an easy install. I also threw the funny playing speaker. With the amp and the new speaker my gameboy screams at me at full volume. Easily
3X the OG volume. Although it does produce quite a lot of audio noise. So be prepared to buy a power cleaner. (Tip thermal tape is your friend)

Nice and loud also easy to install

Amazing products

DEFINITELY louder! ... Now I just need a better speaker to handle the extra power...