the present invention relates to a process and apparatus for use in musical instruments . in particular , the invention is useful for identifying a chord played on a keyboard of a musical instrument , such as the accompaniment manual of an electronic organ , and for identifying the root and the type of chord being played . pursuant to the invention , a microprocessor used in conjunction with the instrument selectively causes the associated circuitry of the pedal and / or accompaniment keyboard of the musical instrument to play automatically in an appropriate octave either the identified root or a sequence of notes which is compatible with the identified root and chord . a pedal override feature is also provided which overrides the chord identification invention when the musician plays one or more pedal notes .