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Hindemith Chord Lab guide

Enter a chord on the piano roll, see its Hindemith group, and audition possible tension movements.

How to use

  1. Enter 3–6 notes on the piano keyboard. On a computer, drag a selected note to replace it. On a phone, tap to toggle notes and swipe the keyboard; dragging is not available.
  2. Select a chord in the progression; click it again to audition.
  3. Choose release, hold, or increase under “Next change” to see candidates.

Six chord groups

The groups are based on interval content. Grid positions show classification, not equal hearing distance.

Group I
No tritone, second, or seventh; not an augmented triad.
Group II
Contains a tritone, but no minor second or major seventh; not diminished.
Group III
No tritone; contains a second or seventh.
Group IV
Contains a tritone and a minor second or major seventh.
Group V
Built from a major third and minor sixth; the root needs context.
Group VI
Built from a minor third, major sixth, and tritone; the root needs context.

Groups I–IV indicate tension direction; Groups V and VI require context and are excluded from direction suggestions.

A change example

C4 E4 G4 is Group I; G3 B3 D4 F4 contains the B–F tritone and is Group II. The example shows how note content changes classification; voicing, register, and rhythm still affect what you hear.

Scope and source

The tool performs a quick six-group analysis from interval sets; it does not replace full musical analysis. Groups V and VI need contextual roots. The classification follows the ontocomc research paper (2025), page 3 and Appendix B. Notes range from A0–C8 and tempo from 40–180 BPM.

Pianet T samples · Greg Sullivan · CC BY 3.0 · Acoustic piano samples · AKAI public domain