New Gear Review: Mod Rex Effects Pedal by Electro-Harmonix
Offering four different modulation sections to process your signal, the Mod Rex furthers Electro-Harmonix’s long lineage of creating unique and innovative effects.
Electro-Harmonix, the Long Island City-based effects pedal company, has been bringing innovative effects to the market for so long that it’s almost surprising that they are still pushing boundaries.
From the very first gnarly tones of the Big Muff to the dripping, thick chorus tones of the Neo-Clone, Electro-Harmonix pedals tend to leave an unmistakable footprint, both sonically and literally.
Enter into that fray the new Mod Rex, a pedal that syncs four different modulation options to a single clock and comes with a bevy of features that give it a unique sonic mangling character.
Features
The Mod Rex comes in a sturdy doublewide case that will be familiar to those who have used EH’s Memory Man Deluxe pedals. As mentioned, the Mod Rex contains four separate effect slots, each of which can be bypassed by selecting “0” in the menu. Each effect can be modulated with its own tempo subdivision, or disabled entirely. The tempo subdivisions range from a whole note to 16th notes, with all the usual variations in between.
The first effect in the signal path is a filter, with low pass, high pass, and band pass options. There are small knobs for the frequency (somewhat confusingly labeled ”depth”) and resonance.
Next comes a pan effect, followed by a tremolo effect. The Mod Rex is able to operate in either mono or stereo; when in mono the pan effect simply becomes a second tremolo, albeit with reversed waveforms. Those wave shapes are the usual suspects—inverted sawtooth, triangle, regular sawtooth, and square—but the ability to select waveform per effect is a very unique feature, and this means that the sonic capabilities of the Mod Rex are immense.
The last element in the chain is a variable mod effect with four choices selectable via a small button: vibrato, flanger, chorus, and phaser. The depth knob here controls the amount of the effect, which makes much more sense than in the filter component. These modulation effects are certainly capable of a lot, and the deep heritage of Electro-Harmonix is clearly felt, yet the limited controls for each means that the Mod Rex might not make a clean substitute for your favorite modulation pedal currently.
It’s important to note that the signal path on the Mod Rex is not exactly as the front panel is laid out; first comes the filter, followed by mod, tremolo, then pan.
While Electro-Harmonix has released multi-effects pedals in the past, the Mod Rex is new in that it has the ability to store 100 presets, each with their own associated BPM. The tempo can also be locked globally with a small button right on the front panel—a very handy addition. There is also a main volume knob, which is not always a feature of modulation-based effects.
The tempo can also be input via a tap tempo footswitch on the front panel, clock to MIDI, or even external pulse via an expression pedal input. MIDI input also means every parameter can be controlled via CC, which is useful when connecting the Mod Rex to your DAW workstation. The front panel does an admirable job of displaying a lot of information, and the four-digit LED display is a smart solution to showing four settings at once while maintaining real estate. Tempo changes fluidly with tap tempos; you won’t get any jumps in audio here.
In Use
Putting the Mod Rex through its paces reveals a lot of sonic possibilities, especially considering the fact that it can be used on a variety of sources due to the pedal’s ability to work in either mono or stereo modes.
Turning off all but one of the effects still gives you a unique opportunity to tempo sync a modulation effect like phaser or vibrato, which isn’t common in the world of pedals. The easy-to-read and simple screen is another feature that makes using the Mod Rex a breeze. Lots of knobs and buttons to tweak make it a great tabletop pedal for synths and drum machines as well, and tabletop users will be pleased to hear that the footswitches are soft press and easy to activate with your hands.
Adding the Mod Rex to a synth signal can transform it completely; the same can be said for guitars or drum machines that run through its path. Given that each effect can have its own tempo subdivision, it’s incredibly easy to set up a preset that has a plethora of potential for polyrhythmic fun.
To Be Critical
One minor niggle that I did notice when using the Mod Rex was a slight clicking sound heard when turning on effects (this occurs when selecting any other subdivision than zero). This was largely dependent on input material however, so your results may vary.
Another minor complaint I had was with the roles of the knobs. The Mod Rex has large knobs to change tempo subdivision for each effect, while smaller knobs (similar to those on the Korg Volca series) change depth, and feedback/resonance. It would have made more sense if those roles had been inverted, given the fact that I was more liable to tweak the depth than the tempo subdivision. And unlike the other three effects where the depth knob effectively acts as a dry/wet control (allowing you to carefully choose how much of the effect you would like), the depth knob on the filter section of the Mod Rex controls the filter’s cutoff frequency. It would have been nice to have a separate dry/wet control for this effect as well.
Finally, having the filter first in the chain was a bit limiting sonically. It may be more preferable for some to have this in reverse order, with the filter following the other effects.
Summing it Up
Electro-Harmonix’s Mod Rex brings a lot to the table, especially given its price of $249. Lots of sonic possibilities, impressive syncing capabilities, and a small footprint means this pedal is going to be useful to all sorts of musicians. MIDI input and the ability to store presets are also valuable additions to this already feature-packed unit.
The Mod Rex is useful for guitarists and tabletop setups alike, though maybe more so the latter given the small size of some of the knobs. That being said, there’s a lot to like in the Mod Rex, unsurprising given its proven pedigree.
Leo Maymind is a producer, DJ, and writer living in Los Angeles, CA. He is obsessed with sound, and you can reach him at lmaymind@gmail.com.
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