Dunlop MXR Custom Badass Modified Overdrive

The MXR Custom Badass Modified O.D. is an overdrive pedal from MXR, the Dunlop brand, carrying the model number M77¹. Dunlop describes it as a classic overdrive circuit with modern modifications for improved performance and versatility¹. What sets it apart from most overdrives is its EQ flexibility: a 100Hz cut and boost control and a Bump switch that engages an alternate voicing, both added on top of the usual tone, output and gain knobs¹².

The pedal was introduced at Winter NAMM 2012, where Guitar World demoed it from Dunlop's booth as part of the MXR Custom Badass line³. Vintage Guitar had reported on it the previous November as an overdrive circuit with modern modifications⁴.

The controls: 100Hz and Bump

Three of the knobs, tone, output and gain, are the standard overdrive set. Premier Guitar's review notes that these are "practically de rigueur" for the type, and that the fourth control is what makes the pedal different².

The 100Hz control is the pedal's signature feature. Dunlop says cutting it gives a more focused EQ while boosting it gives a beefier tone¹. MusicRadar described it at launch as a 100Hz filter control designed to help retain the bottom end when boosting the mids in your tone⁵.

Premier Guitar's reviewer found it does more than tighten or fatten the low end²:

The Bump switch is a miniature button on the enclosure rather than a full-size footswitch. Premier Guitar's review observed that the four small knobs and miniature bump button look a little less robust than the big rubber knobs that once graced MXR pedals². Functionally, it engages an alternate EQ voicing that boosts the lows and mids¹, so you can flip between two voicings depending on the amp and guitar.

Overdrive, booster, or both

Dunlop lists the pedal as an overdrive, built on a classic overdrive circuit upgraded with the 100Hz control and Bump switch¹. RockBoard's PedalPedia entry for the M77 tags it as both overdrive and booster⁶, so players who want a mostly-clean level push with the gain low and the output up can use it that way, though its core design is overdrive.

The pedal is true bypass, as Premier Guitar's review confirms², so it leaves your dry signal alone when disengaged.

Where it came from

The Custom Badass Modified O.D. came from the same MXR team behind the MXR Custom Badass '78 Distortion, released the year before; MusicRadar reported at NAMM 2012 that the team behind that distortion had turned their attention to overdrive pedals⁵. Guitar World's Josh Hart, demoing the pedal at the Dunlop booth, framed it the same way: "Next up in the MXR Custom Badass line is the Modified Overdrive, a classic overdrive circuit with modern modifications for improved performance and versatility"³.

Vintage Guitar introduced the pedal in November 2011 as "an overdrive circuit with modern modifications," including the 100-hertz cut/boost control and a Bump switch that engages an alternate EQ voicing to boost lows and mids⁴.

Pairing it with the '78 Custom Badass Distortion

Dunlop's own recommendation for the pedal is to stack it:

The idea is classic overdrive-into-distortion stacking: the Modified O.D. shapes the front end while the '78 Distortion supplies the heavier clipping, and Dunlop's claim is that the combination yields amp-like gain structures without burying your core tone¹. The '78 Custom Badass Distortion itself carries a Crunch switch that boosts the harmonic content, as Pedal of the Day's review notes⁷, giving the pair two switchable voicings between them.

Videos

Click to load

Click to load

Click to load

News

Questions