Mesa/Boogie Mark I

The Mesa/Boogie Mark I was the amplifier that introduced high-gain preamp distortion to rock, allowing players to achieve saturated lead tones at manageable volumes. Randall Smith's modification of a Fender Princeton — adding cascading gain stages — created a new category of amplifier. Jerry Garcia used a Mark I for its clean headroom and responsive touch sensitivity, while Carlos Santana's singing sustain defined the amp's lead voice. The combo format and relatively compact size made it practical for the Grateful Dead's unique approach to live sound reinforcement.