Thomas Elroy Oberheim (Born July 7, 1936, Manhattan, Kansas), known as Tom Oberheim, is an audio engineer and electronics engineer best known for designing effects processors, analog synthesizers, sequencers, and drum machines. He has been the founder of four audio electronics companies, most notably Oberheim Electronics. He was also a key figure in the development and adoption of the MIDI standard. He is also a trained Physicist.[1]Originally a manufacturer of electronic effects devices (most notably the Maestro phase shifter), and briefly an ARP Instruments dealer, Oberheim went on to create several ground-breaking p roducts 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). Oberheim’s Two-voice TVS-1, Four-voice FVS-1 in 1975, and Eight-voice in 1977, (which was the four voice frame with an external 4 SEM module) were among the first commercially available polyphonic synthesizers. Configurations were based on the SEM. 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 the Matrix-1000 marketed after the acquisition by Gibson.[5][6] In 2009, Tom Oberheim announced that he was manufacturing a new version of his classic analog SEM. In 2011?2012, Tom Oberheim announced a four-voice SEM called “Son Of 4 Voice” (SO4V), as well as an updated version of the classic Two-Voice known as the Two-Voice Pro. The “Son Of 4 Voice”, also known as SO4V, the Two Voice Pro started shipping in 2014. (Wikipedia Source)