I'm looking to make some microtonal music (19/22 tone equal temperament). I want to produce it with midi. Timidity++ used to be able to produce a WAV file from a microtonal tuned .MID file, but it is no longer developed and does not run on modern systems. Is there any free software that can do it? Scala seems like an option, but is a major pain on a Mac.
Microtonal is tricky on MIDI because it separates the space between half-tones into 128 equal notes. I'm surprised any normal MIDI player won't integrate pitch bend as a microtonal parameter - is that how you are doing it?
I've been trying to work on a continuous pitch controller in MIDI. the issue is that depending on the MIDI player, the 0-128 can send the pitch up/down a whole step (like most pitch wheels do) or up/down a whole octave. It seems as though this isn't actually standardized on software synthesizers.
PureData should be able to work with midi on any level you want it to. You can find it for free at http://puredata.info/. It's a bit tricky to get used to, though.
If you're not completely bend on using MIDI, I would recommend OSC. It's a protocol like MIDI, but the interval between half-notes can be split up with as much precision as you want. Not all programs support OSC though… it would be good to check other DAWs/synthesizers you may want to eventually use.
Check out alt-tuner, new microtonal software. It's not free, but it's very easy to use and runs on both PCs and macs: http://www.tallkite.com/alt-tuner.html
You can use the free software Scala to generate microtonal midis (and you can render them, afterwards, with a midi player like SynthFont). http://www.huygens-fokker.org/scala/