SEVEN-OCTAVE, POLYPHONIC KEYBOARD MUSICAL INSTRUMENT Russian patent published in 2010 - IPC G10D17/00 

FIELD: physics; acoustics.

SUBSTANCE: invention relates to a seven-octave polyphonic keyboard musical instrument. The seven-octave polyphonic musical instrument has seven identical circular phonogram plates on pulleys placed in checkered order and rotating with given speed in turns from one of two motors, diametre of pulleys of which is twice or four times different, and keys. The second motor runs at idling speed. On the phonogram plates there are 14 sound tracks which determine the timbre of the instrument, whose figures are made using current-conducting material. Under the rotating phonograms there are fixed phonogram matrices which have insulated sound tracks which are connected by wires to keys which have up to five contacts, the first of which is connected to a low frequency amplifier. When the instrument is working, sound from contra octave to four-line octave are extracted from the first motor, and when the instrument is switched to the second motor, frequency of extracted sounds is amplified two or four times.

EFFECT: design of a musical instrument which provides high and accurate tuning, has timbre similar to sound of bow-instruments and is cheap to make.

7 dwg, 1 tbl