Despite traveling in circles that included jet-setting rockers, he always considered himself a technician. ''I see myself as a toolmaker and the musicians are my customers," he said in 2000. ''They use the tools."
A native New Yorker, Mr. Moog bristled at hours of piano lessons he was forced to take growing up in Queens but had fun in the workroom of his father, a Consolidated Edison electronics engineer.
After reading a magazine article about the theremin, he assembled one. Because of its wide range of octaves, the theremin can sound like a human voice, a stringed instrument, or a deranged animal, and it is manipulated by moving one's hands between two antennas.
Mr. Moog received a bachelor's degree in physics from Queens College, a master's degree in electrical engineering from Columbia University, and a doctorate in engineering physics from Cornell University.
According to the book ''Analog Days" (2002), a history of the Moog synthesizer, Mr. Moog walked into an elevator on his way to his Ph.D. defense and immediately became obsessed with the resonant frequency of the elevator: ''Bob started jumping up and down on the floor (and) somewhere between the fourth and fifth floors he hit the right frequency. The elevator suddenly started bouncing alarmingly in time with his jumps and ground to a halt. Four hours later he was rescued."
With inspiration from composer Herb Deutsch, he created the analog synthesizer and promoted it successfully at an audio engineering society convention in 1964. A novel feature of his instrument was its attack-decay-sustain-release envelopes, which control the way notes swell and fade.
By the end of that year, R.A. Moog Co. marketed the first commercial modular synthesizer.
The instrument allowed musicians, first in a studio and later on stage, to generate a range of sounds that could mimic nature or seem otherworldly by flipping a switch, twisting a dial, or sliding a knob. Other synthesizers were already on the market, but Mr. Moog's stood out for being small, light, and versatile.
