Twelve TheoryMath + Music Playground

Explore interactive music theory and music by numbers through Free Play, Math Mode, Chord Game, Harmonic Cone, Waveforms, Harmonic Polygons, Sheet Music, Musical Circles, and Ear Training.

Interactive module

Harmonic cone

Each cone section is one exact whole-number multiple of the fundamental.

Starting octave
A3
H1H2H3H4H5H6H7H8
Harmonic 110A3216.00 HzMatches equal temperamentRelative mass model · 1× fundamental

Hold a cone section to hear it. Hold more than one to combine harmonics.

1–8 play harmonics · O / P change octave

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