Jason was born in Wichita, Kansas in 1977, but raised in Crystal Lake, Illinois. He studied jazz drums at DePaul University for three years. He only eased into the vibraphone after leaving school, playing it in the indie-rock scene around Chicago with bands like Pinetop Seven and the singer-songwriter Edith Frost.
In the early 2000s he began his collaboration with cornetist Josh Berman and drummer Mike Reed. Since then he was worked in the Chicago jazz and improvisation scene with multiple bands, including Rob Mazurek’s Starlicker and Exploding Star Orchestra, Mike Reed’s Loose Assembly, Josh Berman and His Gang, Nicole Mitchell’s Ice Crystal, James Falzone’s Klang and Ken Vandermark’s Topology and Audio One.
Adasiewicz formed his Chicago-based jazz quintet, Rolldown, in 2004, while living in Madison. In 2008 he founded the trio Sun Rooms, with Nate McBride and Mike Reed.