Using a combination of what Tom had learned about analog synthesizers by becoming an ARP dealer in the Los Angeles area in the early 1970s and his 10 years as a digital systems engineer, Tom designed the DS-2A digital sequencer that would allow the musician to enter a musical sequence of notes and durations directly from the synthesizer keyboard. The 144 step sequencer interfaced with the most of the analog synthesizers available at the time including the ARP 2600, Odyssey, and the Minimoog.   Three transposition settings could be preset and recalled. Each note in a sequence could have a duration from 1/20 of a second up to 8 seconds.