Using a concept reminiscent of (but not identical to) the Moog guitar, Dr. Andrew McPherson applies an electromagnetic resonance system to an acoustic grand piano with amazingly musical results. The basic idea is that electromagnets can excite the strings to varying degrees, in addition to the usual hammers doing so. Key dip position is sensed by a Moog Piano Bar, and the resulting MIDI information is translated by computer into instructions for how intensely the electromagnets should radiate. The end result is nothing less than synth-like envelope control over an acoustic piano.
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