Gravimeter-based musical-instrument swell, expression, or crescendo pedal

摘要

There is provided a swell or expression pedal for controlling swell shades of a pipe organ swell box or pipe chamber, audio level of a virtual pipe organ, or musical instrument expression, responsive to pedal angle relative to the force of the earth's gravity, responsive to pedal depression by a musician's foot. The musician depresses the pedal when additional sound is desired, or to engage different ranks of pipe sounds. As the pedal rotates through an angle, a gravimeter responds to the angular change of the force of gravity relative to it to produce an electrical signal, analog or digital, responsive to the angle of the pedal. This electrical signal may be used to actuate a swell shade motor, controlling sound emanation from a swell box or pipe chamber, to control the functions of a virtual pipe organ, or to control the expression of other musical instruments.