Learn Hand Gesture Music Theory

Scale Degrees I–VII on the Left Hand

Roman numerals describe a note's position relative to the selected key. In C, degrees I through VII use the roots C, D, E, F, G, A and B. One to five raised left-hand fingers select I through V; the index-and-little-finger shape selects VI, and adding the thumb selects VII.

The degree is a movable relationship, not a fixed pitch name. Change the key to G and degree I becomes G while degree V becomes D. This lets one learned gesture progression transpose without teaching the camera a new set of shapes.

Use I–V–vi–IV to hear that movable relationship. In C, the roots are C, G, A and F; degree VI needs the minor world to make Am. Change the key to G and perform the identical left-hand degree order, producing G, D, E and C, with VI again set to minor for Em. The finger vocabulary has not changed, but every absolute root has moved. Watch the Roman numeral and note-name displays together for both passes. If the numeral is correct while a major or minor label is wrong, the degree gesture succeeded and the chord-world control needs attention. This distinction is more useful than memorising one chord list because it transfers to every available key.

See the complete two-hand control map →

Major and Minor Chord Worlds

The left wrist tilt can infer whether the current chord world is major or minor when tilt control is enabled. You can also lock the mode in Settings for a more predictable exercise. The world changes the third used to build a chord: four semitones above the root for major and three for minor.

GestureSynth keeps the selected scale-degree root while changing chord quality around it. This is a playable mapping rather than a full automatic harmonisation of every diatonic chord in a traditional key, so listen to the displayed chord and use the control intentionally.

Triads, First Inversions and Seventh Chords

The right-hand finger count selects one of four chord constructions. The first shape uses a root-position triad voicing, while the second places the third at the bottom for a first-inversion colour. The third adds a major seventh in the major world or a minor seventh in the minor world.

The fourth shape creates a dominant seventh in the major world or a diminished seventh colour in the minor world. These labels describe the implemented interval formulas. They are not guitar fingerings or a claim that every chord automatically follows classical voice-leading rules.

Build and hear Gmaj7 →

Volume, Filter and Octave Are Expression Controls

Right-hand height maps to volume, so harmony can stay constant while dynamics change. Right-wrist tilt moves a low-pass filter, altering brightness without changing the chord notes. Extending the right thumb lowers the voicing by one octave.

These continuous controls are musical expression rather than new chord identities. Practise holding one left-hand degree while moving only right-hand height, then tilt, then thumb. Isolating one dimension makes the connection between motion and sound easier to hear.

Practise the theory in a guided song → · Play chords with the focused player →

Hear Chord Formulas in the Chord Laboratory

Explore 15 chord qualities with exact spelled notes, chromatic root selection, inversions, local audio and WAV downloads. These camera-free reference tools extend the theory guide; suspended, augmented and added-tone chords are not new webcam gestures.

Major Chord Generator → · Minor Chord Generator → · Diminished Chord Generator → · Augmented Chord Generator → · Sus2 Chord Generator → · Sus4 Chord Generator → · Major Seventh Chord Generator → · Minor Seventh Chord Generator → · Dominant Seventh Chord Generator → · Diminished Seventh Chord Generator → · Half-Diminished Chord Generator → · Minor-Major Seventh Chord Generator → · Add9 Chord Generator → · Major Sixth Chord Generator → · Minor Sixth Chord Generator →

Explore Extended and Altered Chord References

Compare ninths, elevenths, thirteenths, six-nine, power chords and five altered dominants. Each generator spells its own exact formula, explains the decisive listening contrast and exports the current voicing. Extended root positions are complete reference stacks; practical voicings may omit tones.

Power Chord Generator → · Major Ninth Chord Generator → · Minor Ninth Chord Generator → · Dominant Ninth Chord Generator → · Minor Eleventh Chord Generator → · Dominant Eleventh Chord Generator → · Major Thirteenth Chord Generator → · Minor Thirteenth Chord Generator → · Dominant Thirteenth Chord Generator → · Six Nine Chord Generator → · Seventh Flat Five Chord Generator → · Seventh Sharp Five Chord Generator → · Seventh Flat Nine Chord Generator → · Seventh Sharp Nine Chord Generator → · Seventh Sharp Eleven Chord Generator →

Explore Suspended Chords and Upper Colors

Compare suspended sevenths, ninths and thirteenths, minor added-note chords, major sharp-eleven stacks and flat-thirteen dominants. Each generator spells its own exact formula, explains the decisive listening contrast and exports the current voicing. Extended root positions are complete reference stacks; practical voicings may omit tones.

Minor Add9 Chord Generator → · Major Eleventh Chord Generator → · Minor Six Nine Chord Generator → · Seventh Suspended Second Chord Generator → · Seventh Suspended Fourth Chord Generator → · Ninth Suspended Fourth Chord Generator → · Thirteenth Suspended Fourth Chord Generator → · Major Seventh Sharp Eleven Chord Generator → · Major Ninth Sharp Eleven Chord Generator → · Major Thirteenth Sharp Eleven Chord Generator → · Minor Major Ninth Chord Generator → · Augmented Major Seventh Chord Generator → · Ninth Sharp Eleven Chord Generator → · Seventh Flat Thirteen Chord Generator → · Ninth Flat Thirteen Chord Generator →