Current idea is to use the following as the main component. It’s powered via 12v DC and has some decent power for driving a load. The TPA3116 is fairly well regarded as a decent sounding Class D amp, so it’s looking like a good match for a 12v car battery. The best part is that it’s only $24.
The other element is the method to stream over the audio. I was looking at streaming via the Bluetooth A2DP spec, which provides 2x stereo sound. The mp3->a2dp->whatever compression doesn’t leave me feeling good about the effect of all that excess transcoding on the audio product.
A couple of good resources I’ve discovered so far indicate that it’s possible tell the bluetooth stack to use an optional codec, such as mp3 to stream. If the optional codec is available on both sides, it can thus be used.
Android should also be able to stream over the audio:https://source.android.com/devices/bluetooth.html
Still looking into what all that entails. If i go the mp3 direct route over Bluetooth using the optional codec tech, then I’ll have to dig deep into that stacks config.