Chord Board

The Chord Board is a color-coded slide rule that displays the notes necessary to form or transpose chords in music. The multi-colored chart is a 2-octave piano keyboard with numbered note positions ~ and a center slide that displays the notes. Created on the island of Oahu, Hawaii and registered in 1979 by Martin H. Samuel, the original Chord Board was printed by Datalizer of Addison, IL. As a practical means of reference, the Chord Board is popular with musicians, singers, songwriters, choirs, composers and arrangers.

Pierre Bernard, of Houdah Software in Luxembourg, programmed and published the Chord Board Slide Rule iPhone / iPod Touch App. (that displays and plays the notes and chords) in English in 2010 and in German in 2011.

The Chord Board App. may be used as a guitar, banjo, ukulele, bass, violin, viola or cello electronic tuner.

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