A 48Khz digital music player for the Commodore 64 (2018)

I don't understand why the `sidtable' conversion is done at run-time. It looks as if one could save quite a few cycles at no size cost by doing it when encoding.

The values in the table depend on the SID model. So on an older SID (6581) you have one table, and on newer SID (8580 or 6582) you have another.

Meanwhile, the Atari computers had a “volume-only” mode that let you send a voltage directly to the audio output.

By setting the paddle ports to a high-speed sampling mode, you could easily build an audio sampler.

Great computers.

Discussed at the time: https://news.ycombinator.com/item?id=16696246

Another trick is to put the replay routine in zero-page, so you can easily increment the pointer. It saves one cycle.

Not just PCM playback, but also realtime decompression, vector quantization.

About 2 bits used per 8 bit sample.

About 7 bits of PCM resolution out of good old SID chip.