Build Quality:4.9 out of 5 stars
Hardware:4.8 out of 5 stars
Electronics:4.8 out of 5 stars
Sound:4.8 out of 5 stars
Value:4.9 out of 5 stars
Average:4.8 out of 5 stars

Check on Amazon

Electro-Harmonix Metal Muff Distortion with Top Boost Guitar Effects Pedal


  • Versatile
  • Powerful
  • Good built quality


  • Way too much treble
  • A bit time consuming

I have said this many times but I will repeat myself once again: once you step into the distortion territory, there is no going back. This simple, yet powerful effect is extremely addictive, pulling you harder and harder each time. Those, who do not get too crazy, might be satisfied with the distortion their amp can bark up. And let’s be honest, some of the models out there can truly distort the hell out of your sound. But I am sure, the majority of you are looking for more. If so, today you will encounter a whole new definition of “more”. Electro-Harmonix Metal Muff with Top Boost will turn your world upside down, shatter the window or two and simply gnarl up your whole existence. If you want to explore some more details and find out the capabilities of this pedal, then keep on reading!


If you have been researching pedals for long enough, you would have encountered Muff series somewhere along the way. Big Muff Pi has been one of the most prominent distortion pedals, but Electro-Harmonix did not stop there (and thank god they did not). They came out with Metal Muff with Top Boost, which is true beast when it comes to delivering mind-blowing metal mayhem. It has meticulous controls with 3-band EQ, a set even some amplifiers do not possess. This way you can really dig deep and tweak everything to perfection. The most distinctive feature here is the Top Boost circuit which can be engaged with a footswitch. Yeah, you have guessed it, it boosts your signal and accentuates the leads to the extreme. Just like any other pedal out there, Metal Muff with Top Boost can be powered either with 9V battery or an optional power supply. The battery compartment is protected with a shell that is screwed down. The design is top-notch, featuring a black textured surface with huge white writing displaying the name of the pedal. When you look at it, you know you are dealing with ethereal distortion and girth. The chassis itself is robust, protecting the insides like a pro. Metal Muff with Top Boost is guaranteed to stay in your rig for years to come since it would be hard to break even if you wanted to. The only downside here is that this pedal is the size of two stompboxes and if your pedalboard is crowded, you might have hard time finding some space for this bad boy.


As I have already mentioned, the control section of the Metal Muff will not leave anyone cold. They allow you to tweak even the smallest details and be in charge of your sound to the fullest. The quality of the knobs themselves is quite nice, at least none of the encoders will fall off mid-performance. But let’s move on to more important stuff: the parameters each of them can modify.

There are two footswitches mounted on the surface. Boost activates the Top Boost circuit, while Bypass allows you to choose, whether the pedal is engaged or bypassed. The control section itself starts with Vol knob, which sets the level of the output. Then we have Top Boost, which works in accordance with the footswitch and intensifies narrow band of the higher frequencies. Treble can deliver up to 10dB of cut or boost in the high-end, Mid can tone down or accentuate the mid-range by 15dB, while Bass emphasizes or attenuates the bottom end by 14dB. Last but definitely not least, we have Dist knob, which adjusts the amount of input gain and is responsible for all the distortion that this pedal can emit.

Electro-Harmonix Metal Muff Sound

Metal Muff with Top Boost is one of the best sounding distortion pedals out there (without any exaggeration). It offers a wide variety of distortion flavors and can easily take you from classic rock crunch to the most defined metal craze. I suggest increasing the effect gradually so that you can see what accommodates your sound in the best way. But if you know that you can handle searing distortion that is saturated with power and girth, you can even be brave and dive right into it. The Dist knob on its own shifts between soft bluesy tones to straight-up fuzzy treat. But as you engage the Top Boost circuit, things take a whole new turn. It accentuates the harmonic content in your sonic range and adds extra bite. You can even dial back some treble and create that punchy low-end depth with just a touch of crispness. Metal Muff with Top Boost is not definitely everybody’s cup of tea, but if you learn how to tame the beast, you will achieve the most spectacular results.  


Electro-Harmonix and its Muff series have fascinated musicians for a while now. However, Metal Muff with Top Boost is a slight different touch to that series. It has the character of its own and offers unworldly distortion without depriving your sound of its best qualities. The ability to achieve almost any type of the effect with simple adjustments makes this fella an essential tool for any rig. If you are not afraid to saturate your sound with texture, character and searing girth, then you should definitely try this one out. Just take your time, experiment with everything Metal Muff with Top Boost can offer and you will be left amazed. Good luck!

Check Availability

Click here to view more from 10 Best Distortion Pedals.


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.