Harmony Mapper

What it does

Pick a key and mode, click any chord to hear it, and see where it can lead. Stack lenses for secondary dominants, tritone subs, modal interchange, and chromatic mediants. Build progressions and export as MIDI.

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  This started out when I vibe-coded a guitar scale fingering generator. It came out pretty good, and I started adding stuff to it: chords, then how chords and scales interact. Then I added charts for other instruments I mess around with: piano, cello, alto recorder. There's a complexity toggle to go from basic harmony to extended/experimental stuff. It's honestly still mostly a toy, but I thought other people might be interested in playing with it. Source is on github, so it's easy enough to run locally and fork. https://github.com/aleshh/gtr-scales

• AS
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