Terry Welty is a veteran audio engineer, bass technician, and product designer with more than three decades of experience in the music industry. His career includes extensive worldwide touring and long-standing work with legendary bassist Geezer Butler, first as his sound engineer in the mid-1990s and later as his bass tech beginning in 2006—a role he continues to hold. Trained in the craft of audio repair, modification, and fabrication from an early age, Welty gained foundational expertise under industry leaders such as Bob Heil, Don Hartwig, and Stan Nickens, developing advanced skills in soldering, speaker reconing, equipment repair, and cabinet construction.

Welty has been part of the design teams behind several high-profile signature products, contributing ideas and technical insight to Geezer Butler’s Signature Bass Guitars with Lakland, Signature Pickups with EMG, Signature Wah-Wah with Dunlop, and the Ashdown Head of Doom amplifier. His background in hands-on engineering and product development also led to the creation of a new fuzz circuit that became the basis for Alan Robert’s Fuzz Off And Die pedal. Working in collaboration with craftsmen Jeff Bradley and Scott Fraser, Welty helped transform the original prototype—built in his basement in 2023—into a refined, artist-branded production model. His work continues to influence modern bass tone, gear innovation, and the technical standards of touring musicians.