Dennis began learning the accordion at age ten under the tutelage of a Finnish American accordionist while living in Michigan. He played at Scandinavian dances in the Detroit area starting in the sixties.

He has a significant repertoire of Finnish, other Scandinavian and various ethnic and popular American standards. He learned many of his Finnish songs in the folk tradition having sat in front of the old bands at dances and listening to recordings.

He has been the accordionist and lead musician for the Kisarit Finnish folkdancers for more that 20 years.