Toz - Geometric Music

You've heard harmony. Now see it.

On the Tonnetz grid, a major chord is a triangle pointing up. Flip it — minor chord. Add a corner — seventh chord. These aren't icons. They're the actual geometric structure of the notes.

Toz makes this 200-year-old music theory map something you can play.

--- ON THE GRID ---

Draw Chords
Drag to connect notes. △ = major, ▽ = minor, ∟ = dominant 7th. Hear the chord as you draw it.

Build Progressions
Link shapes into a sequence. A bar at the bottom tracks your harmonic path.

Set a Key
Tap any note as your tonal center. Pick major, minor, harmonic minor, or melodic minor. The grid shows what's in — and what's out.

MIDI Input
Plug in a keyboard. Every chord you play maps to a shape on the grid, in real time.

Chord Map
A reference for every triad, seventh chord, and scale shape on the Tonnetz. Tap to hear.

--- MADE FOR ---

- Composers who think about harmony spatially
- Music theorists doing Neo-Riemannian analysis
- Students who'd rather see intervals than just read about them
- Anyone who's wondered what their chords actually look like

--- HOW IT WORKS ---

The Tonnetz puts the circle of fifths, major-third cycles, and minor-third cycles on one grid. Chords stop being abstract symbols — they have positions, neighbors, and distances.

Move one note. The shape transforms. So does the sound.

Toz Pro
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