Electro-Harmonix Nano Metal Muff review – a surprisingly versatile distortion pedal that does more than just metal

A small but mighty fuzzstortion for all your metal needs, but this has an appeal beyond the denim and leather cohort

Electro-Harmonix Metal Muff Nano
(Image: © Future / Phil Barker)

Guitar World Verdict

A surprisingly versatile distortion pedal that push your amp into throaty drive or split the atom when maxed, it won't take up much space on your 'board, or much of your budget.


  • +

    Wide range of gain sounds.

  • +

    3-band EQ offers plenty control over your sound.

  • +

    Pedalboard-friendly size.

  • +

    Onboard noise gate.


  • -

    The knobs might be fiddly.

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Few pedals companies have been as prolific as NYC-based Electro-Harmonix over the years. And that tradition continues apace today, including the production of multiple versions of some of the brand’s most popular pedals – but how many Big Muff versions do you need? Scrap that: we all know you can never have too many Big Muffs! 

You can get a total of eight different Muffs in Nano-sized enclosures, but only three of them get the Nano prefix. Here, we are looking at the Muff that is built for the rigours of metal guitar.

Billed as being “built for the player who demands nothing less than hard-hitting distortion and an intense, aggressive sound”, the Nano Metal Muff features three-band EQ alongside the standard Volume and Gain (Distortion) knobs. 

It also features a noise gate with a variable threshold, which can be very effective in cutting out any hiss and hum if you set it just right.

At its mildest, with Distortion at minimum and the output volume cranked up, the pedal is capable of a raunchy overdrive, but it goes way beyond that to full-on cranked-to-the-max distortion. 

Electro-Harmonix Nano Metal Muff

(Image credit: Electro-Harmonix)

Now, that could be true of many distortion pedals, but it’s the three-band EQ that’s main deal here – each knob covers a huge range, so you can really sculpt the sound, maybe tweaking the midrange with a scoop or some cocked-wah resonance, or going further into some extreme tone-wrangling.

It’s black and says Metal on the box, but it’s way more than that.


  • PRICE: $84 / £79
  • TYPE: Fuzz/distortion pedal
  • FEATURES: Buffered bypass, noise gate
  • CONTROLS: Volume, Gate, Distortion, Treble, Mid, Bass, Bypass footswitch
  • CONNECTIONS: Standard input, standard output
  • POWER: 9V battery or 9V DC adaptor (not supplied) 24mA 
  • DIMENSIONS: 70 (w) x 111 (d) x 50mm (h)  
  • CONTACT: Electro-Harmonix

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Trevor Curwen

Trevor Curwen has played guitar for several decades – he's also mimed it on the UK's Top of the Pops. Much of his working life, though, has been spent behind the mixing desk, during which time he has built up a solid collection of the guitars, amps and pedals needed to cover just about any studio session. He writes pedal reviews for Guitarist and has contributed to Total Guitar, MusicRadar and Future Music among others.