Improvisation generally consists in creating a Melody suitable for a given Chord Progression. This means that a score containing only chords is given, and a melody must be composed in such a way that it fits or sounds well with those chords.

That part of the melody corresponding to each chord is composed, in most cases, by notes belonging to a certain Scale related to the chord. According to the CHORD SCALE THEORY, the scales related to a given chord are those containing the notes of the chord.

IMPROCHART is an Improvisation Chart based on the CHORD SCALE THEORY, which automatically gives us all the Scales related to a given Chord. It consists of two rotating discs, one being card and the other plastic. It comes with instructions, scale tables and a practical protective case.