So, let me first start by saying "it is what it is." The amp is small (4" speaker) and light (3 watts). I got this used amp essentially free. Never could bond with it. I don't like to run amps off battery and this one makes a ton of noise with my 1Spot power supply. Much quieter stock with just a 9v battery. The Overdrive channel was just too much - too muddy, too crunchy. Unusable for me. Clean was fine. It wouldn't sell on Craigslist so I found the Greta speaker upgrade thread and decided to try the Visaton speaker. Result - much more usable, so far. Speaker isn't broken in, but the crunch seems to be lessened to something I can work with. I'm really happy with my 20 minutes of effort and a new $8 speaker. I also discovered the baffle was floating loose, so I hot-glued that back down and dusted the whole thing out. Fun little refurb project. Here's a few pics. If anyone else has or does mod these, I'd be curious to hear about it. MP3 in would be really helpful.