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Marshall ShredMaster Review

Marshall ShredMaster Review

The heavy pedal that became famous at the feet of Jonny Greenwood delivers surprises with colors that range from explosive to doomy, and yes—shreddy.

Top U.K.-build quality. Surprising range of unique distortion colors. Interesting interactions between EQ controls.

Could be too dark for shredders who rely on sizzling top end.


Marshall ShredMaster


It’s a great irony that the player most popularly associated with the Marshall ShredMaster is probably Radiohead’s Jonny Greenwood. Clearly, Greenwood is a guitar magician. But he is hardly a shredder in the conventional sense. So, what is it about the Marshall ShredMaster that it was given such a … um … shreddy name and yet finds favor among so many not-shreddy players? As is turns out, the explanations are many. And there are plenty of reasons shredders would find much to love in this sturdy, U.K.-made pedal too.

Blast and Squish

The ShredMaster was short-lived in its original incarnation. Introduced around 1991, it was discontinued just a year later. The timing of its release explains how it would have fallen into Greenwood’s hands and shown up on the band’s 1993 debut Pablo Honey. (I’m going to bet that the ShredMaster is doing a fair bit of the heavy lifting in “Creep’s” super-crunchy choruses.) The ShredMaster shows up all over Radiohead’s other ’90s LPs too—usually paired with Greenwood’s solid-state Fender Eighty Five. This pedal/amp pairing gives us some clues as to why the relationship endured.

See, the ShredMaster has a wonderful capacity for dark, compressed tones—the kind that would probably blend well with Greenwood’s humbucker-equipped Telecaster Plus and a bright, powerful solid-state amp. But those dark and compressed tones can also work well for super-fast picking when you’ve got high-octane pickups and a high-gain amp in your chain, working as a kind of glue as you move through fast lines and legato phrases. That’s one explanation for how this pedal bridges the chasm between metal and big indie. But while the ShredMaster doesn’t have as wide a vocabulary as Marshall pedal stablemates like the Guv’Nor, it’s an impressive source of heaviness that can work across many styles.

Because the ShredMaster can seem dark at EQ levels that, on other pedals, would translate to fairly even response, it’s important to get a feel for how the bass, contour, and treble controls work together. Of these, the contour is probably most critical. At settings in the clockwise half of its sweep, it adds a bossy midrange—PAF humbuckers gain a trashy metal edge but single-coils can sound a touch cloudy and fizzy. Left-of-center settings scoop the mids, sound more amp-like, and let more detail shine through. For most of my experiments I preferred to live in this zone.

In general, toppier treble settings also sound best. They enable single-coils to growl and will enhance sustain in humbuckers—giving bridge pickups a feral edge or, in the case of neck PAFs, a smoky heaviness that works well even with considerable volume and tone attenuation. (In general, the ShredMaster isn’t super responsive to changes in guitar input.) One should not be afraid to use a lot less bass from the ShredMaster either. While it can add welcome heft to a scooped, treble-heavy setting, it’s often a source of fogginess that puts a damper on the pedal’s most exciting and dynamite sounds. A good practice is to park the bass at noon, dial up treble and contour to levels that make your guitar sing best, and then add or subtract bass to taste.

The Verdict

Marshall wasn’t misleading us when they gave the ShredMaster its name. Its compressed, high-gain capabilities make the pedal a great partner for fast fretwork. But what any open-minded player will discover is that the ShredMaster, in spite of its name, can play many roles. It can lend heaps of mass and enhance sustain, as well as add a singing or stinging side to leads, or menace to a tame signal that needs to cut and slice on demand. And while its $249 price tag exceeds that of many pedals that drive an amp to nastiness, the ShredMaster’s unique voice and high-quality, U.K. build suggest it’s a pedal that could serve at the front line of any studio pedal collection or as a fixture on a board—offering both gigantic distortion tones and many exciting surprises over the course of a long and useful life

Marshall BluesBreaker, DriveMaster, The Guv'nor & ShredMaster Demos | First Look