Diagram of harmonic relations in music
A modern rendering of the Tonnetz . The A minor triad is in dark blue, and the C major triad is in dark red. Interpreted as a torus, the Tonnetz has 12 nodes (pitches) and 24 triangles (triads).
In musical tuning and harmony , the Tonnetz (German for 'tone net') is a conceptual lattice diagram representing tonal space first described by Leonhard Euler in 1739.[ 1] Various visual representations of the Tonnetz can be used to show traditional harmonic relationships in European classical music.
^ Euler, Leonhard (1739). Tentamen novae theoriae musicae ex certissismis harmoniae principiis dilucide expositae (in Latin). Saint Petersburg Academy. p. 147.