He has released three albums of songs and performed extensively in clubs and concert halls as a solo artist and as a member of various ensembles.
In live performance, Dewan accompanies his singing with a home-built electric zither, outfitted with eight humbucker pickups and 88 strings, sometimes piped through a leslie cabinet or guitar effects pedals.
He was an original member of the Blue Man Group Tubes house band, for whom he composed musical scores.
When it is time for the projectionist to advance the strip to the next panel, Dewan's voice is typically heard singing "boop" in close imitation of the noise traditionally used for this purpose.
Dewan has created a series of what he terms "shrines", constructed of wood and other materials, such as light bulbs, clocks, photographs and bottles.
The shrines range from about one to six feet tall and often evoke New England church architecture with their lean geometrical spires.
The cabinetry he built for his recent series of electronic instruments, created in collaboration with his cousin, Leon Dewan, often continue some of the visual ideas behind the shrines.
Together they have designed and built a series of synthesizers in custom cabinetry, often reminiscent of either New England churches or 1940's school house architecture.
Dewan has created album art for others, such as the cover of David Byrne's Uh-Oh, They Might Be Giants' Lincoln, Beat Circus' Dreamland, and the interior artwork of In the Aeroplane Over the Sea by Neutral Milk Hotel.