New Gear Review: Nano Metal Muff by Electro-Harmonix

Joining its two larger siblings, EHX’s Nano Metal Muff aims to offer the same massive tonality in a much smaller package.

Long Island City’s Electro-Harmonix have long been a household name in the world of effects pedals. Their classic Big Muff distortion needs no introduction, and has spawned a bevvy of other Muff models over the years which offer various takes on its iconic sound.

The evolution of the Muff line includes darker offerings which bear the name Metal Muff. Available in three iterations which include a larger model with Top Boost, as well as a “Micro” model with a few less controls, the Nano Metal Muff clocks in at the smallest of the bunch.

But metal guitars need not sound nano. So, can this tiny black box supply the big, nasty, up-front tones needed to cut through metal? Let’s find out.

Features and Use

The Nano Metal Muff is very simple mono in/mono out stompbox that fits in the palm of your hand. It runs on 9v of power via either the jack on the back of the pedal or battery. Like the Metal Muff with Top Boost, there are three bands of EQ available on the Nano, however the most notable difference between Nano Metal Muff and both its larger siblings is that the Nano offers an on-board noise gate.

Anyone who has ever “chugged” knows that the spaces in between those punishing palm mutes sound best when they’re tight. And having spent much of my professional touring career playing metal, there are few pro rigs I’ve seen which don’t include a noise gate in the chain. I do wonder why EHX didn’t include this feature in the Nano’s larger siblings, however it is a welcome inclusion here and a nice additional selling point for those already attracted to its compact size.

From a tactile standpoint, I found the design choices on the Nano Metal Muff to be smart on EHX’s part. The EQ knobs are conveniently detented at the noon position, providing valuable reassurance you’re not boosting or cutting when not intending to. Each band of EQ on the Nano Metal Muff has a unique dynamic range: the Bass knob offers +/-14dB, the Mids band offers +/-15dB, and the Treble band offers +/-10dB.

The activity of the aforementioned noise gate is indicated by a small green LED on the top of the faceplate. When fully counter-clockwise, the gate is not engaged; the further you turn it clockwise, the more you will hear the gate. Being that this is such a compact pedal, it’s natural you won’t find controls for attack and release here.

There is a “Status” LED next to the gate indicator which shows whether the pedal is engaged or bypassed (or rather in “buffered bypass” mode, which is its default and only way to bypass). Here, the output jack is connected to the input jack via a “buffer circuit”, providing an output impedance of 600 ohms.

Now let’s remember, this is a very small pedal, so the knobs are close together. This is to be expected here, and not something I consider to be a fault; just be careful when tweaking your settings and refrain from complaining about your fat sausage fingers.

Ok, but how does it sound?

Putting the Nano Metal Muff through the paces, it became clear very quickly that it covers full-throttle, high-gain duties masterfully, and with ease. The further past 12 o’clock you push the distortion, a nice smooth and sustained quality begins to emerge, with a hint of added compression as you push further towards max distortion.

The more I tweaked the settings, I found that the harder you push this pedal, the more color emerges. Is it tube-like? I would say not. However, it rips. If you stack a couple of these on either side of your stereo mix and smash out some power chords, brace yourself.

I found the three-band EQ to be useful and utilitarian, and expectedly not surgical. The implementation of the various headrooms per-band were interesting to me from a design standpoint, and practical in use; you never are reaching to boost more or cut less than the pedal has to offer. The mid band provided crucial bite and cut while still retaining an impressive richness, even when pushed hard. The lows added crucial size and weight which was controlled nicely by the gate in relevant applications. The highs proved to be clear and present while not overly shrill, so long as they are applied carefully and with taste.

This initial sort of buzzy/fuzzy non-tube-like quality of this pedal brought me back to my early teenage days before I owned a tube amp and really understood what that sounded like. But not in a cheap, first guitar pedal kind of way. If you go direct with this pedal, you may get a little of that quality. However, you can also push it to around 80% of where you want your overall distortion to be, and get the rest of your grit from some natural tube breakup.

To Be Critical

I feel it’s worth mentioning that as blistering as the Nano Metal Muff can sound, I wouldn’t describe this pedal as being particularly versatile. I found the more modest distortion settings to fall a bit flat, both dynamically and in terms of tone. For lesser distortion settings, I would likely aim to pair this with another unit or two for added dynamic control and character. However, who would reach for this pedal for modest gain applications? Plug it in, turn it up, and shred. That’s what it’s built for.

I suppose you can also argue that you can’t use the gate independently here if you’d like to apply it to your signal only sometimes. This can negate the inclusion of this feature if say, you’re using it live and switching back and forth from lead to rhythm parts. Perhaps on a future model that isn’t of the Nano branding, EHX would consider putting the gate and distortion on two separate switches. Then again, there are also dedicated gates!

Summing it Up

Overall, I think the Nano Metal Muff is a great value for what it brings to the table. At a very modest price of $72.70, this pedal delivers not only pro-sounding distortion, but also the added functionality of an on-board gate, which is so commonly paired with heavy guitars.

Though probably not the top candidate to run the complete gamut of metal tones (is there another pedal that can at this price point?), this little black box of shred is a very worthy contender for clean and controlled punishment where needed, thanks to its lean and powerful EQ and handy gate. The Nano Metal Muff is indeed another job well done by the folks at Electro-Harmonix.

Dan Gluszak is a producer, mixer, and engineer based in Los Angeles, California. He also doubles as a touring and session drummer.

Please note: When you buy products through links on this page, we may earn an affiliate commission.