A few weeks back I put the speakers in. Here's the run down. I had already built a mounting plate to attach the vent surrounds to from the inside that makes the surrounds stick out the requisite .25" from the skins on the front. That attaches with screws inside the frame. I picked up some speakers at Fry's. They're 12 volt car speakers, 3.5" across. Those were the smallest they had. They have a little tweeter that protrudes, so I needed a spacer between the surround mounting plate to hold them back a bit. So I cut this with my circle jig on the router:
I've got several ways to cut circles. If the radius is bigger than 9" or so, the circle jig on the bandsaw is best, but it requires a skinny blade to turn with the cut or you get drift. I also have an adjustable circle cutting plate for the router where you move the router. This rig is just a piece of plywood that my router is screwed to underneath. And then I put a pin--a cut off nail--into a hole at the radius I want to cut. It produces clean, near perfect circles, especially small ones. These holes fit the speakers well:
So the speaker screw into this plate, and the plate screws into the mounting plate for the vent surrounds, and that plate is screwed to the frame.
I also got a little kit from Carl's electronics a few weeks back for a stereo amplifier. I think the kit was $20 and it took 15 minutes to solder together. I am running a signal from the ipod to that amplifier now and then the signal from the amp goes to the speakers. The amp takes 5 watts that I am running off of a power distribution board. I had seen some droids that had puny sound systems and I didn't want mine to end not being heard. This system is plenty loud. I have to dial the Ipod way back.
I just ordered a little remote control unit for the ipod today from Amazon that will let me control the tracks. It's not quite the capability of some of the remote systems, but I think it will be fine for now. I'm still going to work out the kinks in the Picaxe/VMusic2 system, but the ipod tracks will work now.