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Electro-Harmonix XO Stereo Polyphase Guitar Effects Pedal

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Product 150134
Product Price $0.00
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The Electro-Harmonix Stereo Polyphase Effects Pedal resurrects the popular Polyphase pedal as part of the Electro-Harmonix XOdie-cast series. Now in ...Click To Read More About This Product

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Don't Forget

A powerful effects favorite returns in stereophonic triumph!

The Electro-Harmonix Stereo Polyphase Effects Pedal resurrects the popular Polyphase pedal as part of the Electro-Harmonix XO
die-cast series.

Now in stereo and an improved housing, the Stereo Polyphase Effects Pedal features the same features and controls that so many
guitarists loved and relied on to crank out lush, otherworldly tones from the original.

Featuring envelope/sweep switch, feedback level, rate, envelope sensitivity, envelope modulation, and modulation rate.

  • Controls
  • Env./Sweep: Switches the effect between a phaser with an adjustable speed automatic sweep, and a phaser with an envelope-driven sweep mode.
  • Feedback: Controls the phaser
  • feedback/resonance
  • Rate
  • Env. Sens.: Controls the sensitivity of the effect to the input signal.
  • Env. Mod.: Controls the depth of the envelope controlled sweeps
  • Mod. Rate: Controls the speed of the LFO
  • Comes equipped with a 24 Volt/100mA AC external power adapter. Use only the power adapter supplied.

Review Snapshot

by PowerReviews
Electro-HarmonixXO Stereo Polyphase Guitar Effects Pedal

(based on 3 reviews)

Ratings Distribution

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  • 1 Stars



Reviewed by 3 customers

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(3 of 3 customers found this review helpful)


Stereo PolyWOW

By Endy

from San Juan Capistrano, CA

See all my reviews

Comments about Electro-Harmonix XO Stereo Polyphase Guitar Effects Pedal:

This will offer you a breadth of new tones, but you do have to tool with it a while to understand the interplay between the controls. You are getting at LEAST three pedals in one, though; a phaser, a phase-wah (brilliant!), and a phase-envelope (SUPER BRILLIANT!). This will open us a lot of new territory, and can cover a range of bases normally requiring several pedals to fulfill. Once you start pairing it with other pedals though, this thing goes from excellent to out-of-this-world. Crazy versatile.
First up, I'm a bass player. I play a Geddy Lee Jazz through a pretty big pedal rig and an SWR Redhead. This is an incredibly powerful tool that does wonders for tone (I've played a bit on guitar with it and it shines brilliantly in both bass and guitar range., and services well both in the incredibly subtle 'flavor' effect way and in the stupidly psychedlic 'special' effect way. Easy control navigation, expression pedal input and stereo outputs make this top of the game in phasers. The frequency range is wide, and the relative positioning of the frequency dials let you focus on what frequencies you wish to highlight. In all modes, the feedback control determines the extremity of the effect. It doesn't get to the upper echelons of crazy, but it does get pretty q-ey. The rate control only functions in LFO mode, and ranges from a pretty big, maybe 10-second cycle to a microscopically small spread that adds an almost ring-mod wackiness to the sound. The shimmer factor is definitely very present, and you can change the LFO shape between triangle and square wave, the latter allowing for some pretty crazy textures when paired with a distortion beforehand at a faster rate; I use a big muff, and it sounds like a bloody Death Star when set up properly. The envelope mode is easy, intuitive, and MINDBLOWING; The cross between a phaser's sound and an envelope filter's dynamism provides some very killer wah tones. The sweep is determined by the interplay between the set gain level (allows you to tune for higher or lower output instruments, and basically serves as a sensitivity control) and either fast or slow mode; fast sounds right at home in a slow grooving fingerstyle funk, while fast is the kind of fun burp that is ideal for slap playing or funk guitar. Expression mode turns it into a wah pedal with a very interesting tonal play that is markedly different from standard wah pedals; almost more transparent, with a good handle on the original tone. Combined with pedals, it performs beautifully; paired with a tremolo, it creates beautiful staggered phase sweeps; a fuzz beforehand generates the best kinds of synthy nastiness; running it in envelope mode following another envelope filter creates talk-box like OWs and OHs, with a Bassballs-like quality (with obviously more tonal control). A favorite of mine is to run a slow filter sweep with a Freeze in front of it, allowing you to catch different points in the sweep (phasing the phased signal: Inception time!). Beautiful tonal machine.
Build is solid; solid chassis is pretty much indestructible. Knobs are solid. Input jacks are true bypass, tight and don't crackle. Power supply is not your usual, so don't lose the supplied wall-wart. Stereo phasing is a beautifully trippy innovation that DAZZLES on guitar, especially with a medium-fast rate. Too bad I play bass! The sounds, pots, and chassis are all top notch, nothing else I can say. I've dragged this thing through hard gigging, and it holds up like a tank. plus, the paint job is gorgeous. Gotta rock in fashion, you know?
I got this thing used. Even at full price, this thing is pretty well-equipped to boost your musical library by it's value. For my own discount here, though, I don't feel I can supply an accurate analysis of it's value at full price.

(1 of 3 customers found this review helpful)



By teles4ever

from North Bergen, NJ

See all my reviews

Comments about Electro-Harmonix XO Stereo Polyphase Guitar Effects Pedal:

If you're looking for a small stone, this ain't it. Small stone is pronounced, polyphase is very subtle. Even with all setting to the max phase with, this is not strong enough. rate can get really fast, which is good.Env. mode doesn't shine because of the subtleness of the effect. I believe phase pedals should be used before overdrive. this one has a envelope filter so in a way you have to use it before OD. and with all the subtle quality of this pedal, you will NOT hear a thing through overdrive.And I believe this is the time to introduce some stereo input pedals. It's funny how I can do stereo delay and chorus, flange, phase but cannot combine them in stereo. Hear me!!!


Incredibly versatile

By Anonymous

from Undisclosed

Comments about Electro-Harmonix XO Stereo Polyphase Guitar Effects Pedal:

I got the polyphase because I didn't just want a phaser that would turn on and do that same old tired sweep that has been used a million times. With 3 modes of control plus a lot of knobs to tweak, I can get a lot of different sounds. With fuzz I like to go into expression pedal mode and leave it at a sweet spot to get really throaty almost synth like tones with the feedback/resonance up. Another thing I like to do is go into square LFO mode at a fast to medium speed and push the expression pedal all the way forward so that you don't hear any phasing, then play a chord and pull back on the expression pedal. Sounds cool. Slow envelope mode allows you to give this great texture to clean rhythm playing without being bogged down with an LFO dictating your rhythm. The phaser also sounds great with my synth.

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