> > Does CVSD work only for voice, or can it do music? tones? > > CVSD works excellently for any sound. I use a now-obsoleted > DSP for sound reproduction. They are hungry little monkeys > though, and as you say it's easy to gobble up memory. I'm in, > or will be in, the same position as you. One of these days I'll > have to implement CVSD without the DSP as I use up the last > of those available. To keep the fidelity I'm used to I don't see > a way around using a lot of external RAM. The system of CVSD > I'm familiar with is 1-bit serial, which may be difficult to compress. > If it were 8-bit parallel there may be some hope I would imagine (but I sometimes have an active imagination) that CVSD would be quite easy to implement on any PIC with an A2D (depending of course on desired audio bandwidth). For 5 kHz bandwidth (arguably better than an AM radio station) a sampling rate of 10 kHz+ or 100 uS / sample is required. Processing should be simple enough. Serial ROM access may be a bottleneck. RM . -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics