Ok so this is awesome. I've been tinkering for days now, and gosh dang it I can't get the darn speaker to go louder than a whisper. Followed the wiring diagram, tried two different amps and two different resistors. I'm using 60/40 lead/tin flux, and tried both the speaker linked in the post, and a different one, a 4ohm. This one. both speakers produce no more than a whisper. I used this amp. Using 26 gauge wire. Tried different resistors too, 330k on order right now. I'm about $70 into this $15 amp. Clearly I'm doing something wrong but just can't figure out what. OP and the subsequent post by Vulrath showed slightly different wiring schematics and I tried both. And while I don't have proper baffle on either speaker, the temp I rigged from card board did nothing. Sorry to bother you guys but if you have any thoughts on what Im doing wrong, I would gladly welcome a suggestion. Thanks and great work!