Lattice Harmony is an app for iPad that makes musical harmony a visual and interactive experience. Notes and chords are arranged on a two-dimensional triangular grid known as a tonnetz according to their harmonic similarities and their relationship to the tonic note. Chord progressions can be generated by interacting with the lattice using an intuitive multi-touch interface. MIDI input can be sent wirelessly to Lattice Harmony to generate a live animation of the harmonic structure of a piece of music.



  • Generate harmonies using an intuitive multi-touch interface
  • Chord voicings are chosen automatically to maximize harmonic and melodic continuity
  • Wirelessly connect to external instruments via WiFi and use Lattice Harmony as a MIDI controller
  • Includes dozens of instruments


  • Create animated visualizations of harmonic structure of music in MIDI form

  • Wirelessly connect external MIDI sources over WiFi


  • Lattice Harmony enables hands on exploration of just-intonation

  • Compare how a harmony sounds in just-intonation and in equal-temprament by flipping a switch