Since this amp seems very simple to put together, if you really wanted to go DIY you could do component upgrades. Most of the time they are transformer or capacitor upgrades. Some believe that component upgrades can push "cheap" equipment with good circuitry designs into something that's great. Tried looking up mods for this amp, couldn't find much.
Chris is right, you have to be careful with Class D type amps. Tom will upgrade the boards to whatever caps you want. You can either have him buy them, or mail the caps, etc. to him. He'll do the soldering for you. I asked Tom about an upgrade of the power supply caps from 4700uF caps to 10000uF caps. He said each one would cost about $15 more because he does not buy them in bulk. He said he would not recommend spending money on that though because it was just not worth it (I would not really hear any difference). I trusted his opinion and went with the stock caps. He did say that the toroid upgrade was a wise choice for multiple amps.
I can tell you from looking at what is on the board, these are high quality components.
