[mdre]

Seconded, this looks great! Didn't have time to do more just than a test to see how it works, but I think I ran into a problem in fifths mode when the second key of the interval was outside the span of my two octave keyboard, so there should be perhaps some sort of an octave limiter setting. Oh, and I don't have any sound in the app, but I use VSTs anyway.

Also, would be great to have triad inversions. (larger chords aside...) I'll surely do some learning when I get some free time.

[FinalDestiny]

Thanks for the feedback! I'll see if there's a good way to manage the octaves.

Curious why the sound isn't working, are you using MIDI & which OS do you use?

[mdre]

I use Windows 10 21H2, a bass station 2 as a midi controller and I have like 5 audio output devices. Only one of them is the real one, which is my audio interface, so with no way of choosing the output there will be problems. Wondering if there is an easy way to use ASIO with js-based apps?

I ended up a DAW to get midi from the keyboard and route to both a VST and to a virtual loopmidi port - which I prefer to have nice sounds.

[FinalDestiny]

Wow, that is big brain as it gets! I'm sure it's possible but it may have to be done on the application layer. Thank you for sharing your workaround