Electro-Harmonix Nano Operation Overlord Allied Overdrive Review

EHX shrinks its hugely flexible OD pedal with impressive, amp-like results.

Electro-Harmonix Nano Operation Overlord Allied Overdrive
(Image: © Electro-Harmonix)

GuitarPlayer Verdict

An amp-style overdrive that offers great versatility for guitar, bass and beyond.


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    Amp-like tone and feel.

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    Powerful EQ.

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    Tiny footprint.


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The Electro-Harmonix Operation Overload pedal is a great-sounding stereo overdrive pedal that puts tons of tones at your fingertips. But what if you, like many other guitarists, don’t really need stereo operation? EHX has thoughtfully delivered the new Nano Operation Overlord Allied Overdrive, a mono pedal that creates the same overdrive and distortion tones as its bigger sibling, but in a smaller box.

The first thing you’ll notice about this EHX overdrive is that it is tiny. Yay! The second thing you’ll notice is that the power-strip-hogging wall wart is not. Oh well. More important than any of that is the sound quality, and the little Overlord scores a victory on that front, with open, amp-like tones and smart features that make it compatible with just about any instrument, including bass and keyboards.

EHX has squeezed six control knobs on the Nano pedal’s face. They include volume, dry level and gain, and treble, mid and bass controls for the active three-band EQ. There’s a boost button to select between Normal and Boost modes, and a three-way switch to choose lo, normal or hi input levels, making it easy to match (or mismatch) the pedal to hotter or weaker signals..

The heart of the Nano Overlord is three JFET gain stages that provide the amp-style overdrive. I plugged a Fender Strat into the Nano Overlord and got a super-transparent Jimi tone — not too clean, but not too distorted. The three-band EQ provides a lot of range, but I really liked the tone with everything at noon. Cranking the gain knob higher gradually dirtied things up, but not to the fuzzy or fizzy realm. When I wanted more distortion and sustain, I engaged the boost (switchable both on the front panel and via an external switch).

With just these functions, I had a great range of rock and blues sounds that worked equally well with single-coils and a humbucker-equipped Dean guitar.

The Overlord gets even more interesting with the dry level control, which lets you add your uneffected signal to the overdriven tone. This is cool for guitar, but it works really well for bass, where you need to retain some articulation amid the dirt. Using the dry level, I was able to keep all my attack and low end while still enjoying some cool Entwistle-style grit.

The control also worked wonders on a Hammond organ instrument in Garage Band when I plugged my iPad into the Overlord. This is a sweet drive pedal with a super-tiny footprint that adds life and vibe to a lot of instruments. Props to Electro-Harmonix for delivering a hip take on a tried-and-true concept.


CONTACT ehx.com
PRICE $89 street

CONTROLS Volume, dry level, gain, treble, mid, bass. Boost switch. Hi/normal/low input-level switch
EXTRAS Three amp-like JFET gain stages provide low- to medium-gain sounds in Normal mode. In switchable Boost Mode a classic pedal-style overdrive circuit is added before the JFET stages to increase overall distortion