Micro-Frets

Micro-Frets was an American electric guitar and bass manufacturer established in 1967 in Frederick, Maryland by Ralph Jones. The guitars combined unique body shapes and idiosyncratic color schemes with proprietary technology such as the Calibrato vibrato arm, individual rolling nuts for each string, and even an early wireless transmitter. While never produced in great quantities, the guitars today enjoy a cult status. Past players include Carl Perkins, Mark Farner of Grand Funk Railroad, and Martin Gore of Depeche Mode. Genesis' Mike Rutherford converted a Micro-Frets Voyager into a 6-string bass.

http://www.guitarplayer.com/gear/1012/micro-frets-voyager/13032

http://guitarradioshow.com/micro-fret-guitars-500-words-with-adam-p-hunt/

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