graue/luasynth

Audio framework in Lua

luasynth's Issues

Add explicit sample rate support

One way to implement this would be to pass the sample rate as an argument to each unit's .new() constructor. Then the wrapper could make it available as state.sampleRate.

Stuff sounds different when sample rate changed

I've been using this command to test sample rate changes:

./luasynth osc -oscType Square -freq 200 -length 10 \
  | ./luasynth adsr -attack 30 -decay 500 -sustainLevel -6 -sustainLen 1000 \
  | ./luasynth filter -filtType Notch -center 600 -q 5 \
  | ./luasynth delay -len 900

separately with export RATE=44100, 22050, and 88200. It sounds slightly different at 44.1KHz and 88.2KHz (if you convert the 88.2KHz back down to 44.1KHz, invert it and mix with the 44.1KHz, there's an echoing buzzy sound). And it sounds really different at 22KHz, mostly I think due to the oscillator, and the way it's generating square waves (it should ideally be bandlimited and not a literal "square" wave), but I think there's more than that going on and I'm not sure what's up here.

This issue is a reminder to investigate.

Support Windows in driver

It wouldn't take much to make the main.lua command-line driver work under Windows — same stuff as this commit for moon-noise.

A slightly more ambitious goal would be to split out the FFI-dependent common functionality here (fwrite, fread, isatty and binmode) into a small library, perhaps put it on LuaRocks and make both projects use it.