Who was the sound engineer responsible for the Woodstock sound system?

Bill Hanley was the sound engineer responsible for the Woodstock sound system. His company, Hanley Sound, designed and supplied the large-scale public-address system that carried the festival's music across Max Yasgur's farm in Bethel, New York.

Hanley was a pioneer in concert sound reinforcement at a time when outdoor festivals had no established formula for serving audiences of Woodstock's size. The organizers originally expected roughly 50,000 people, but more than 400,000 arrived. Hanley's system used speaker towers and custom-built equipment to project sound over the enormous crowd and helped establish modern festival audio practices.

The system was innovative but could not perfectly cover the sprawling site; many attendees far from the stage heard only a distant or indistinct performance. That limitation is an important part of the story and does not diminish Hanley's role. Tom Dowd was a prominent recording engineer, Owsley Stanley worked in recording and live sound, and Bob Heil later became known for touring sound systems, but none was the principal engineer behind Woodstock's 1969 sound system.