Don’t own one already? Purchase a stock MXR Phase 90 Block Logo Reissue or MXR Phase 90 Script Logo Reissue and have it modified.
The MXR Phase 90 has come in a variety of packages over the years but at the core is the same phase circuit. Our Classic Overhaul mod is designed to compliment the stock sound of the vintage models while adding additional options and improvements that gigging musicians expect. Our Modern Overhaul is designed to add some more experimental features to the Block Logo reissues.
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| Classic 1974 Overhaul Mod: $120 For Vintage or Handwired Reissues 1. True Bypass 2. Install LED and Pulsing LED circuit 3. Intensity Knob 4. 45/90 Toggle Switch 5. DC Jack | Modern Overhaul Mod: $90 For most Block Logo Reissues 1. Script Mod 2. Mix Knob 3. 45/90 Toggle Switch 4. Volume (internal) Trimpot 5. Slow Mod |
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| Flutter Mod Add-On: $65 Compatible with all Phase 90s 1. Second LFO circuit installed 2. New Rate and Depth knobs 3. Mini Rate LED installed on front | Expression Pedal Jack Add-On: $50 Compatible with all Phase 90s 1. 1/4″ Expression Pedal Jack |
The Script mod restores the reissues to be more in line with the vintage Phase 90 circuit. The modification reduces some of the pedal’s internal distortion, creates a more subtle and well balanced effect with a bit less resonance, and also reduces the upper-midrange boost in the signal. A large part of this mod includes removing R28 which is a feedback resistor.
The Intensity Knob allows you to decrease the strength of the phaser. The knob shown in the photo above is the Intensity control.
The Mix Knob allows you to mix your dry signal with the phase shifted signal. The dry signal is your original guitar tone. The wet signal sounds like a vibrato effect. The pedal in its stock form is about a 50/50 blend of those two sounds so you can dial in more or less wiggle than before.
The Volume Trimpot allows you to increase and decrease the output of the pedal. This is great if you find yourself overloading the next pedal in your chain or if you’re getting lost in the mix. This is a small dial that is mounted on the circuit board- you will need to remove the bottom panel of the pedal to make this adjustment.
The Phase 45 Switch replicates the more subtle tone of the MXR Phase 45. This modification involves installing a toggle switch to select either a Phase 45 tone and the “script logo” Phase 90 tone. The mod does not convert the pedal to a 100% replica of a Phase 45 but it does closely approximate the tone of the more subtle tone of the Phase 45 which cannot be simulated by simply using an Intensity control.
The Slow Mod comes from years of customers asking for a slower sweep from their Phase 90. The stock rate at the slowest cycle takes about 7 seconds to complete. Our mod changes that to around three times longer at the 22 second mark. This long, slow sweep is a great way to add texture without sounding out of place in a setting where swirling effects just do not belong.
Our Flutter Mod adds a second LFO with Depth and Rate knobs to give a totally unique sound to the pedal. We recommend setting the stock Rate knob down low for a long sweep (now with a 3X slower sweep thanks to the Slow Mod which is included as part of the Flutter Mod) and use the added Flutter controls to add some shimmering vibrato and pseudo-random univibe tones to the pedal. A picture of the completed mod can be seen above; A prototype video can be seen at the bottom of this page. Please note the pedal will no longer have room for a 9V battery as the circuitry will fill the battery compartment.
Check out our MXR Phase 90 Expression Pedal page for more info on controlling your phaser with your foot.
Below is an assortment of Phase 90 videos that we’ve recorded over the years: