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MXR Phase 90 -- ADVANCED

Phase Shifter, JFET based


A great-sounding phase shifter used by the likes of Eddie Van Halen ("Unchained") and many others.

You must use matched FETs for the circuit to work. The value of the zener diode depends on the FETs you use. Use sockets for these parts.


Possible mods: "The resistor you pull to get rid of the feedback (and change the sweep) is the red 22k at the top of the schematic. The resistor to change the level is the 150k which connects between the collector and base of the PNP transistor: 120k to reduce gain, 180k to increase it." Rob Strand

For offboard wiring instructions check the offboard wiring project page.

tonepad_phase90.pdf 115.2 KB-- Pez 90, Rev.6.Sep.30.2007

Yes. See our ordering page for all available boards.

MXR Phase 90 US$ 11.00

Small Bear Electronics



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