Mod Electronics Phase/Off review – a phaser pedal so good you won't mind assembling it yourself

For the DIY enthusiast with a steady hand on the soldering iron, this phaser from Mod Electronics might just do the job of one, two, or even three classic modulation units

Mod Electronics Phase/Off
(Image: © Mod Electronics )

Guitar World Verdict

You might have to build it yourself, but the sounds are well worth firing up the soldering iron for, with this 2 and 4-stage phaser capable of doing the classic Phase 90 and Mu-Tron thing, and a whole lot more besides.


  • +

    Incredibly versatile phaser.

  • +

    Wonderful sounds.

  • +

    The self-assembly aspect keeps the price down.


  • -

    Well, you have to make it yourself.

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My fascination with building things ended a long time ago when I played with Legos. Since then, I’ve become more of a prima donna when it comes to assembling anything, but I still know many musicians who love tinkering with and building gear. 

So, for my brethren who fall under the latter category, Mod Electronics has provided them with the satisfaction of building their own pedals and amplifiers with DIY component kits that come with detailed, step-by-step instructions. From what I’ve gathered, as long as you have patience, a steady hand, and decent soldering skills, you can tackle any of these kits. 

Now, while I didn’t take part in building the Mod Electronics Phase/Off pedal that was sent for review, I’m going to use this space to relay how incredible it sounds. And frankly, if I ever find my way around a soldering iron, I just might build one myself. That’s just how remarkable this Phase/Off stompbox is.

According to Mod Electronics, the Phase/Off “is a four-stage phaser pedal based around the Sound Semiconductor SSI2140 voltage-controlled multi-mode filter.” For neophytes not familiar with what that means, the legendary Prophet-5 Rev’s 1 and 2 polyphonic analog synths used “SSM” filter chips to achieve their acclaimed idiosyncratic sounds. 

The new SSI2140 filter chip is an improved update of the original SSM chips used in those vintage synths, and is now being employed in the Phase/Off and configured as an allpass filter to contribute to its distinct phase shifting. The Phase/Off features knobs for Depth, Rate and Regen to go anywhere from subtle to intense modulations of its triangle LFO phasing. 

Mod Electronics Phase/Off

(Image credit: Mod Electronics )

In addition, a “Stages” mini-switch toggles between four-stage or two-stage phasing, while the “Mode” mini-switch can be set to LFO (for classic phasing) or to Manual (disabling the LFO in a fixed phase mode controlled by the Depth knob for alternative filtering effects). Lastly, the pedal comes in a heavy-duty aluminum housing (that can be custom-painted), is true-bypass, and operates on 9VDC with no battery connection. 

Call it unconscious bias toward an off-brand stompbox, but I didn’t expect the Phase/Off to sound so musical in its smooth phasing. I’ve been quite fond of my Phase 90 and Mu-Tron Phasor variants, but the Phase/Off took me by surprise by unintentionally being able to combine the sonic characteristics of both of those classic phasers into one unit.

Set to four-stage phasing and with all three knobs set in-and-around noon, the Phase/Off nails the ramped-up swoosh of a script-era Phase 90, but can also drizzle in a drippy funked-up swirl that sounds so infectious with clean guitar. 

Mod Electronics Phase/Off

(Image credit: Mod Electronics )

Pushing the controls to their outer limits delivers thick and chewy extremes of swoosh reminiscent of a Mu-Tron Phasor. Hell, if you dial the knobs a particular way, you can almost ape the ringing pulse of a Uni-Vibe with a dollop of phase.

You can’t go wrong either way, but I’ll point out that its two-stage setting offers warmth and softness to its swirl, whereas, I believe, players are more likely to hang with the richly detailed and lush four-stage phasing.

I mentioned earlier that there’s a synth chip at play here, and what’s so cool is you can hear a hint of that filtering when you dial in settings for throbbing vibrato, vocal-like “Wow” sounds, synth stabs, and psychedelic rise-and-fall swoosh. It’s all so sweetly packed into this pedal that I’d say it’s worth the time and sweat for the build.


  • PRICE: $79
  • TYPE: Phaser pedal (requires self-assembly)
  • CONTROLS: Depth, Rate, Regen, Mode switch (LFO, Manual), Stages switch (2-stage/4-stage)
  • POWER: 9V DC from pedalboard power supply (not included), ~50mA
  • CONTACT: Mod Electronics

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Paul Riario

Paul Riario has been the tech/gear editor and online video presence for Guitar World for over 25 years. Paul is one of the few gear editors who has actually played and owned nearly all the original gear that most guitarists wax poetically about, and has survived this long by knowing every useless musical tidbit of classic rock, new wave, hair metal, grunge, and alternative genres. When Paul is not riding his road bike at any given moment, he remains a working musician, playing in two bands called SuperTrans Am and Radio Nashville.