There is also the Bela cape for the beaglebone which, along with a special os for the beaglebone, gives you a very low-latency platform for synthesis, programma

There is also the Bela cape for the beaglebone which, along with a special os for the beaglebone, gives you a very low-latency platform for synthesis, programmable with Supercollider or puredata, and lots of analog and digital io.