[ad8e]

It's possible to generate 12 ET too, by rounding all the keys and harmony changes. Just as 12 ET is a good approximation to Just Intonation, Just Intonation is also a good approximation to 12 ET. The tones lose some accuracy but gain compatibility with MIDI interfaces.

However, it would be hard for me to implement this feature, since I have no midi devices, no midi experience, and my browser (Firefox) also doesn't support WebMIDI.

I'm thinking about implementing record-and-replay, since the playback and storage-format are already done, but midi will likely be deprioritized unless there is significant interest.