Les played his first jazz gig in 1974 with his father, Duffy Senff. He attended high school in Redmond, OR, and attended Central Oregon Community College, playing in the college band. He earned his degree in finance from the University of Oregon and played with the Duck Marching Band. He currently works in marketing for Cenex Seed Co in Tangent, OR, while continuing to play the music he loves.

Les has been a member of the OJB since 1988. He has also performed with the Wall Street Jazz Band in Bend, the Starlighters in Eugene, the Silver Fox Band in Eugene, and the Willamette Valley Polka Band