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Thomas Elroy Oberheim (*1936 in Manhattan / Kansas), known as Tom Oberheim, is the
inventor of the first polyphonic music synthesizer.
He has been the founder of three audio electronics companies. The companies are Oberheim, Marion Systems & Seasound. He participated in the
development of the MIDI standard.
Oberheim Electronics was founded in 1973 and manufactured audio synthesizers and a variety of other electronic musical instruments. Originally a manufacturer of electronic effects devices, and briefly an ARP Instruments dealer, Oberheim went on to create several ground-breaking products in the early days of synthesizers and electronic music including the
DS-2 (one of the first digital music sequencers) and the
Synthesizer Expansion Module (SEM). The first commercially available polyphonic synthesizers, Oberheims
Two-voice TVS-1,
Four-voice FVS-1, and
Eight-voice, which was the four voice frame with an external 4 SEM module, configurations were based on the SEM.
Originally released in 1974, the SEM is one of the classic discrete analog synths. The Two-voice synthesizer included a two channel voltage controlled sequencer, and the Four-voice and Eight-voice machines included a rudimentary Programmer, capable of recalling sound settings.
Oberheim's later synths like the
OB-X and
OB-Xa abandoned the relatively bulky SEMs in favor of individual or compact voice cards, and common cabinetry and power supplies. Oberheim continued to make synthesizers until the late 1980s. Other notable Oberheim synthesizers include the
OB-1 (monophonic), the
OB-8, the
Xpander, the
Matrix-6, the
Matrix-12, and
Matrix 1000.
Oberheim closed its doors in 1986, when it was acquired by
Gibson Guitar Corporation, a larger musical instrument manufacturer, who made, in collaboration with
Don Buchla, the
OBM-X.
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In 1987, after the sale of the Oberheim company, Tom Oberheim created the company Marion Systems (named after his daughter Emily Marion) the new company specialized, once again, in sound products. The first product was a 12-bit to 16-bit option for
Akai's S900 sampler. Marion Systems was formerly in Santa Monica and later Lafayette in California. After the end of Marion Systems, Tom developed Seasound.
Recently, Oberheim began selling an updated version of his original SEM with upgraded electronics. As with the original, the new SEM was a true analog synthesizer. In 2009, he released a second version of the SEM with MIDI control.