MXR Phase 90

The MXR Phase 90 is a phaser effects pedal originally designed in the 1970s by MXR.

The Phase 90 was released in 1974. It was the first pedal sold by MXR and helped launch the company. The original came in a simple orange enclosure with MXR's "script" logo. In 1977 MXR changed its logo to the current "block" logo. There was a transitional period in which some Phase 90’s with script logos had box logo circuits, and vice versa. Production ceased when MXR went bankrupt in 1984.

When Jim Dunlop bought the MXR brand, production resumed. The Dunlop production models have modern additions including an LED to indicate when the effect is engaged and the option of using a power supply instead of a battery. There are a few variants available, including the standard block logo version, a reproduction of the script logo version, and an Eddie Van Halen signature model. The 1974 Hand Wired Phase 90 is a recreation of an original 1974 pedal using NOS (New Old Stock) electronic components.

The Phase 90 has an orange enclosure. It has a simple control scheme consisting of only one knob.

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