Smith's modifications gave the small amps much more input gain, making them much louder as well as creating a high-gain, distorted guitar tone.

[3] However, he would hop freight trains nearly every weekend from Santa Barbara back to the Bay Area to see friends and return to the Beat coffee houses and bookstores of Berkeley.

[3] Smith wanted to participate in the burgeoning San Francisco music scene, having been taught clarinet and a little sax by his father, but he took up drums, as it was the easiest to learn quickly.

Mesa/Boogie began with a practical joke when Smith was commissioned to secretly convert the 20-watt Fender Princeton of a local guitarist into a significantly louder 100-watt amp without altering its appearance.

"[3] In addition to the amp repair business, Smith supplemented his income by building concrete foundations for summer houses and rebuilding Mercedes-Benz automobile engines.

[4] As the demand for his amps grew, Smith decided to move his workshop out of the Prune Music storefront to get away from the distractions of the store having become a busy local hangout.

[9] Smith produced a number of custom variations of the Boogie through the late 1970s, with options including reverb, a five-band graphic EQ, various speakers (most often Altec or Electro-Voice), koa wood jointed cabinets, and wicker grills.

[10] The IIC was introduced in 1983 to fix a noticeable "pop" when switching channels, while subsequent improvements to the effects loop resulted in a handwritten "+" designation on the rear of each amplifier's chassis.

"[11] Early adopters included heavy metal guitarists like Metallica's Kirk Hammett and James Hetfield, who was dissatisfied with Marshall amps at the time and wanted something "percussive tight and in your face.

"[12] Guitar World cited the IIC+'s use on Master of Puppets as the primary reason for its "holy grail" status in the rock and metal genres, while noting the amp was also a favorite of top session musicians at the time like Steve Lukather.

As the 1980s came to a close, the complicated features and boutique styling of the Mark series began losing popularity in favor of simpler designs by Marshall, Bogner, and Soldano.

[3] With a "raw, aggressive bass-heavy sound"[14] and sporting a characteristic steel, diamond faceplate, the Rectifier was Mesa's take on a "big, monster-metal head" and intended to look threatening compared to the Mark amps.

While an array of bands have used Rectifiers—including Korn, Tool, Soundgarden, Foo Fighters, and Blink 182[9]—Smith has said the overwhelming success of the amp with its distinctive sound and styling has led many people to associate the entire Mesa brand exclusively with metal, despite the company's roots in the "Fender legacy" and its initial reputation as a "hippie outfit" aimed at blues players.