Do you love classic rock? If your answer is yes, there’s no doubt that the MXR M78 Custom Badass Distortion will serve you well. As the name implies, it has that late ‘70s hard rock overdriven tone.

From saturated rhythms to burning leads, you can get all the essential crunch from this trusty vintage-style distortion pedal with modern capabilities.

MXR has, in fact, made pedals since the late ‘70s. However, the MXR M78 Custom Badass ’78 Distortion is a modern invention. In essence, it’s a classic design but hot-rodded almost beyond recognition. You can squeeze lots of gain out of this sports car-red old-school stompbox.

MXR M78 Custom Badass Distortion Sound

Distortion might be the effect where different pedals sound the most unique. This is mostly due to the frequency curves they produce. A classic rock distortion tone must be meaty and wild without excess grit and harsh treble content. That’s the exact kind of drive you’ll get from the MXR M78 Custom Badass Distortion.

The fuzzy and smooth yet defined tone with all dials in the middle reminds me of classic albums by bands like Led Zeppelin and Thin Lizzy. Turning the distortion up another quarter makes the sound so dense you could almost cut it with a knife, without getting muddy at that. Max out the distortion with the CRUNCH button, and you get a sweet bite with sustain for days. Best of all, it’s still controllable and defined.

The MXR M78 Custom Badass Distortion is very responsive to your playing and maintains a dynamic signal at high settings. This balance between harmonic enrichment and dynamics is the formula for a truly huge guitar sound. It’s worth noting that you’ll want a guitar with humbucker pickups for the best results with powerful overdrives like this.

I also want to point out that it’s not only a nostalgia-inducing effect. It’s suitable for more modern styles as well, especially if there’s an alternative or indie element to your music.

MXR M78 Custom Badass Distortion Features

Under the hood, this is a factory-modded overdrive circuit that they gave higher gain for an over-the-top hot tube distortion effect. The circuitry is top quality, and the whole pedal seems like it could handle decades of touring.

There are actually two different clipping modes, and these are what you switch between with the CRUNCH button. The second one pushes the clipping diodes harder, giving you more harmonic content.

As for controls, it has the typical three-knob setup. OUTPUT controls the volume, DISTORTION sets the intensity of the effect, and TONE lets you adjust the bass and treble. The range of these parameters is quite generous with a maximal system gain of 43 decibels.

With these controls and two clipping modes, you can get a vast variety of sounds out of the MXR M78 Custom Badass Distortion pedal. Rhythms and leads, old-school and modern rock tones, it’s all there. And if you love classic rock, it’s one of the best distortion pedals you can get.


  • Size: 4.5 x 5.5 x 2.5 inches
  • Weight: 0.84 pounds
  • Input impedance: 1 megaohm
  • Output impedance: 6 kilohm
  • Nominal input level: -22 dBV
  • Maximum output level: -2 dBV
  • Noise floor: -84 dBV
  • Bypass: Hardwire true-bypass
  • Powering options: 9-volt battery or DC power supply (not included)

In case you want more details about the features and specifications, here’s the user manual.

Is MXR M78 Custom Badass Distortion Your Best Retro Distortion Pedal?

If old-school hard rock is your passion, it’s definitely among the best distortion pedals you can get. It has the sound and the look, and it gives you a modern level of control. You can switch between vintage pedal drive and amp-like crunch instantly with the CRUNCH button.

Whether you want to rock out with a convincing cover band or play your own meaty rock songs, the M78 Custom Badass can take you there. For the face melting solos and smooth rhythm carpets of classic rock, this is an ideal dist box.

If this doesn’t sound quite like what you’re going for, take a look at these other great overdrive pedals.

That concludes this MXR M78 Custom Badass Distortion review. Thanks for reading.