GAMMA is a guitar effects pedal and amplifier brand of The Acoustic Control Corporation. Acoustic was founded by Steve Marks and his father in the late 1960s in Los Angeles, California. Renowned for its powerful Acoustic 361 bass stack, the brand became a favorite among musicians in the '70s and '80s, especially for performances in large venues. Iconic players like Larry Graham, Robbie Krieger, John Paul Jones, John McVie, and Jaco Pastorius contributed to the popularity of Acoustic amplifiers, utilizing them to craft their distinctive sounds. The line of GAMMA solid state amplifiers came first then around 2023 the effects pedal range was launched.