Game Boy CleanAmp v1.2 Audio Amplifier Universal - RetroSix

The GB/GBP/GBC instructions for this amp ask you to bypass the gameboy's amp, but this product is missing an important feature, that without makes audio actually worse.
A fair number of games actually play music or sounds in stereo. The built in amp will combine the Left and Right audio if you use the speaker. This product does not. instead opting to take only one side. Surely someone who "reverse engineered and analyzed lots of the Game Boy's components." would realize this.

For the GBA the instructions ask you to amplify the speaker output. I guess that works if you just want to make the GBA louder.

I wouldn't have wasted my time if I had known it only amplifies the right audio channel. I know the gameboy only has one speaker, but the audio typically outputs both channels to that speaker. While this mod does make the volume louder, its only for the right channel. You'll miss so many of the instruments and sound effects in games that use both channels. It was very noticable in pokemon crystal, sounded like a different song entirely. This also makes LSDJ, nanoloop, impossible to compose chiptune music with. Very frustrating that this isn't at least stated anywhere. I would have bought a DIFFERENT audio amp that supports stereo to mono mixing.

While it works, noticeably amplifies the sound and cleans it up, it is not stereo sound. While the GameBoy only has a single speaker, it appears the actual games are splitting certain sounds between a left and right channel. This mod only amplifies one channel, so many games are missing sounds. Tetris is missing notes, super Mario land is missing coin sounds, etc. There are ways around this from what I understand, but that is not ideal and you have to wire up additional mods. I hope this can get fixed with a newer board revision. As it stands, this is kind of unusable.

So I ended up grabbing a new power regulator along with the audio amp. Right now, I'm using the factory speaker that came with the Game Boy. Overall, quality is good and sound is effective (and very loud). Since I was careful and used plenty of flux, I did not run into any issues with the quality of the solder pads on the board. A few improvements for this mod and the offerings of items on Handheld Legend:

- The directions for the DMG-01 install have me solder a small wire on the end of a component (resistor or capacitor. Not sure). If we are having pads on the board already, why not just have another pad available to solder onto? Even when being careful, I still shifted the component. This part of the design introduced unneeded risk for the install

- Handheld Legend offers new speakers. Cool, except the wire length was not adequate for this mod. If I missed another item posting to get a new speaker with longer wires, that should be a more obvious option. Otherwise, consider defaulting the speakers sold with longer wires for things like this mod. Due to this, I just stayed with my original speaker

- I'd like to see recommendations for taking advantage of the increased power output of the amp. Better quality speakers? Higher impedance headphones? Is this mod a good direction to take for an audiophile Game Boy?

- It wasn't clear to me if this amp would clean up any of the white noise on the audio line (it doesn't, at least on the headphone output. Makes sense, but still). Perhaps a specific disclosure on this only amplifying total power of the output would be good, especially given the name of the mod (CleanAmp).

That's all I got. I'm a happy customer, but think there is still room for some improvement on the mod itself and how it's sold.

It’s nice and loud, but only one of the stereo channels is connected. Wack.

This little amp does a great job. I will say though, it is REALLY tiny. The soldering pads are very small, so you will want to make sure you have something to hold things steady and some small wire to go with it. And I would recommend at least the larger capacitors (680uF) from the dehum/dehiss kit: after I installed the amp without them, there was a fair amount of background noise. Once I put those capacitors in, the game sound is very clear. Video shows the stock speaker at max volume compared to the amp at max volume (without the louder solder bridges).