The chip doesn't really have the performance for audio processing. It operates at 1 MHz, but since it operates on one bit at a time, you'd probably only be able to perform a couple of additions on each audio sample. So not really enough for effects.
Thanks, that makes sense--maybe operate 16 in parallel? Logic (human) still probably wouldn't stop me from trying if I had one laying around--what the chip would do outside of the design discipline, that is. :)