Robert "Bob" Yannes (born 1957) is an American

electronic engineer Electronic engineering is a sub-discipline of electrical engineering that emerged in the early 20th century and is distinguished by the additional use of active components such as semiconductor devices to amplify and control electric current flow ...

who designed the SID audio generator chip for the

Commodore 64 The Commodore 64, also known as the C64, is an 8-bit computing, 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in ...

and co-founded digital synthesizer company

Ensoniq Ensoniq Corp. was an American electronics manufacturer, best known throughout the mid-1980s and 1990s for its musical instruments, principally Sampler (musical instrument), samplers and synthesizers. History In spring 1983, former MOS Technol ...

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

Apple IIGS The Apple IIGS (styled as II) is a 16-bit personal computer produced by Apple Inc., Apple Computer beginning in September 1986. It is the fifth and most powerful model of the Apple II family. The "GS" in the name stands for "Graphics and Sound" ...

home computer.

Biography

Robert Yannes graduated from

Villanova University Villanova University is a Private university, private Catholic Church, Catholic research university in Villanova, Pennsylvania, United States. It was founded by the Order of Saint Augustine in 1842 and named after Thomas of Villanova, Saint Thom ...

in 1978. He started out as an electronic music hobbyist before being hired as a chip designer at

MOS Technology MOS Technology, Inc. ("MOS" being short for Metal Oxide Semiconductor), later known as CSG (Commodore Semiconductor Group) and GMT Microelectronics, was a semiconductor design and fabrication company based in Audubon, Pennsylvania. It is ...

which had become a part of Commodore. Albert Charpentier recruited Yannes partly for his music synthesis knowledge. He has been infatuated by

electronic music Electronic music broadly is a group of music genres that employ electronic musical instruments, circuitry-based music technology and software, or general-purpose electronics (such as personal computers) in its creation. It includes both music ...

since the early 1970s. He claims the song '' Lucky Man'' by

Emerson, Lake & Palmer Emerson, Lake & Palmer (informally known as ELP) were an English progressive rock Supergroup (music), supergroup formed in London in 1970. The band consisted of Keith Emerson (keyboards) of The Nice, Greg Lake (vocals, bass, guitars, producer) ...

influenced him more than any other single song, and also lists

Kraftwerk Kraftwerk (, ) is a Germany, German Electronic music, electronic band formed in Düsseldorf in 1970 by Ralf Hütter and Florian Schneider. Widely considered innovators and pioneers of electronic music, Kraftwerk was among the first successful a ...

and

Mike Oldfield Michael Gordon Oldfield (born 15 May 1953) is an English retired musician, songwriter and producer best known for his debut studio album ''Tubular Bells'' (1973), which became an unexpected critical and commercial success. Though primarily a gu ...

among his influences. He designed the ''MicroPET'' with help from Albert Charpentier which became an unintended prototype for the

VIC-20 The VIC-20 (known as the VC-20 in Germany and the VIC-1001 in Japan) is an 8-bit entry level home computer that was sold by Commodore International, Commodore Business Machines. The VIC-20 was announced in 1980, roughly three years after Commod ...

home computer. He designed the single-chip sound

synthesizer A synthesizer (also synthesiser or synth) is an electronic musical instrument that generates audio signals. Synthesizers typically create sounds by generating waveforms through methods including subtractive synthesis, additive synthesis a ...

voice chip SID (6581) with enough resolution to produce high-quality music. However, he was unable to refine the

signal-to-noise ratio Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to noise power, often expressed in deci ...

which he desired. He hoped the chip would find its way into

polyphonic Polyphony ( ) is a type of musical texture consisting of two or more simultaneous lines of independent melody, as opposed to a musical texture with just one voice ( monophony) or a texture with one dominant melodic voice accompanied by chords ...

/polytimbral synthesizers. The SID chip was his first attempt at a phase-accumulating oscillator, the heart of all Wavetable-lookup synthesis. After he left MOS Technology he co-founded

in 1982. The Ensoniq sound chips had multiplexed oscillators designed in such a way that it was possible to produce more voices per chip, typically 32 for Ensoniq's ''DOC'', ''OTIS'', and ''OTTO'' sound chips (48 for the final ''OTTO-48''). Given less time constraints than for the ''SID'' chip design, a proper MOS

op-amp An operational amplifier (often op amp or opamp) is a DC-coupled electronic voltage amplifier with a differential input, a (usually) single-ended output, and an extremely high gain. Its name comes from its original use of performing mathem ...

could be implemented to eliminate signal leakage and an improved filter to achieve high resonance. Current designs include waveform interpolation, digital filters, and digital effects.stud1.tuwien.ac.at - Interview with Bob Yannes
1996-08-30

References

{{DEFAULTSORT:Yannes, Robert Commodore people Computer hardware engineers Living people 1957 births