Bob Yannes

Robert "Bob" Yannes (born 1957) is an American electronic engineer who designed the SID audio generator chip for the Commodore 64 and co-founded digital synthesizer company Ensoniq.

He designed the Ensoniq 5503 Digital Oscillator Chip (DOC) which was used in both commercial synthesizers and the Apple IIGS home computer.

He started out as an electronic music hobbyist before being hired as a chip designer at MOS Technology which had become a part of Commodore.

He designed the single-chip sound synthesizer voice chip SID (6581) with enough resolution to produce high-quality music.

Given less time constraints than for the SID chip design, a proper MOS op-amp could be implemented to eliminate signal leakage and an improved filter to achieve high resonance.