If you have seen these things mini ipod stereos etc.
Here is my rendition of it.
Ofcourse its no Zvex tube version. (although I may do my own version).
You could use a more powerful power amplifier. But it uses parts common to us guitarist DIYers.
I actually designed this as a christmas present for my g/f's brother, who is a DJ. He wants wireless headphones but doesnt want to shell out for a really good pair. He has a 0.5w FM transmitter. He plans to use his mp3 player with radio to tune in on his broadcast frequency. Connecting the headphone out of the "decks" to the fm transmitter. However, his mp3 player does not get loud enough to hear in live situations. Hence this little design. It converts the speaker level signal to the level expected by the 386 amplifier (I hope). Which is in turn connected to his headphones. that way he is free to dance or whatever the hell he does when "DJing" in his local club. I am submitting this here for advice on possible improvements, mistakes etc. What do you experts think, is this correct?
(http://homepage.ntlworld.com/paul.nelson666/Mp3%20player%20amp.JPG)
I haven't got a clue about output votages of the MP3 thing and how much you should attenuate it.
But we all know 386's can handle overload quite well. ;D
This is my stereo bench amp. Tiny wee thing, kicks out 2W - sounds great thru a 2x12" (hint).
Uses TBA820M chips (49p each), pcb layout included etc etc. 56R/100uF control gain(-ish).
http://tacashi.tripod.com/elctrncs/poweramp/poweramp.htm
(http://i30.photobucket.com/albums/c345/stompbox_layouts/miniamp.gif)