MXR Phase 90

The MXR Phase 90, introduced in 1974, is one of the most iconic phaser pedals in music history. Developed by MXR co-founders Keith Barr and Terry Sherwood, it was the first pedal released by the company and set a new standard for compact effects. The Phase 90 features a simple single-knob design that controls the speed of the phasing effect, delivering warm, swirling modulation. Its rugged construction and rich, versatile sound made it an instant success and a staple for guitarists across genres. Over the years, the Phase 90 has been reissued in various forms, including the Script Logo version (modeled after the vintage original) and the EVH Signature model.

Historical Development

Origins: The Phase 90 was inspired by radio signal phase-shifting circuits and adapted into a musical tool. It was one of the first compact phasers available, offering a user-friendly alternative to larger units like the Maestro Phase Shifter.
Impact: The pedal's success established MXR as a leader in effects pedals during the 1970s. Its warm analog tone and simplicity made it a favorite for live and studio use.
Reissues: Dunlop acquired MXR in the late 1980s and has since reissued several versions of the Phase 90, maintaining its legacy as a classic modulation effect.

Notable Players

Eddie Van Halen: The Phase 90 is synonymous with Van Halen's early sound, prominently featured on tracks like "Eruption" from Van Halen I. He often used it with a slow sweep before distortion for subtle modulation.
David Gilmour (Pink Floyd): Known to use phasers like the Phase 90 for atmospheric textures in his solos.
Josh Homme (Queens of the Stone Age): Frequently uses it to add depth and movement to his guitar tones.

Popular Settings

The single Speed knob makes it easy to dial in classic tones:

Van Halen Sweep: Set Speed to around 9–10 o'clock for a slow, subtle phase effect that enhances lead tones.
Funky Rhythms: Speed at noon for medium-fast modulation, ideal for choppy rhythm playing.
Psychedelic Swirl: Speed at 2–3 o'clock for fast, dramatic phasing reminiscent of Hendrix-inspired tones.

Legacy

The MXR Phase 90 remains one of the most celebrated phaser pedals ever created. Its warm analog sound, durability, and simplicity have made it a go-to choice for guitarists spanning rock, funk, metal, and beyond. Whether used subtly or dramatically, its timeless design continues to inspire musicians worldwide.