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MidValleyFx Double-Amp Distorter Review

MidValleyFx Double-Amp Distorter Review

Two wide-ranging op-amps with a delightfully rowdy edge.

A Patrick James Eggle Macon Single Cut (a Les Paul style guitar with PAF-style humbuckers) into a Friedman Small Box set for semi-clean, and a 2x12 cab.
0:00 – Pedal off, amp sound only.
0:06 – Gain at minimum, Tone at maximum, Volume at 55%, Clip switch down
0:28 – Gain at 75%, Tone at 6-%, Volume at 55%, Clip switch up



Can move from aggressive to surprisingly great low-gain tones. Quality handbuilt circuit. Nice price.

Not always the smoothest or creamiest distortion.


MidValleyFx Double-Amp Distorter


Ease of Use:



Oregon-based MidValleyFx is very much a home-brew concern, with Andrew McNicholas crafting pedals shaped as much by his own guitar-noise preferences as by classic templates, while his wife, Tori, designs the pedals’ graphics and manages other aspects of the business. The pair often dabble in the obscure and esoteric, but the twin-LM741 op-amp-driven Double-Amp Distorter proves they also make pedals of great utility. This stompbox boasts medium- to high-gain distortion capabilities with voicings ranging from clear and cutting to thick, meaty aggression.

Double Trouble
The Double-Amp Distorter’s control complement is, in general, a classically simple interface, with knobs for gain, volume, and tone. But there’s also a 2-way switch to alter how the silicon 1n4001 clipping diodes do their work. (MidValley also uses 1n4007 diodes in the Double Distorter). The up position generates swift attack and extra clarity. The down position generates a spongier, more compressed feel. The pair of LM741 op-amps, meanwhile, will generate as much gain as most guitarists are likely to need.

The pedal is powered via a traditional 9V center-negative barrel jack, with no provision for an internal battery. The circuit itself is comprised of a perforated board that’s entirely handwired with discrete components. It’s very old-school and reassuringly well built.

A Distorter by Name…
And a distorter, most definitely, by nature. I tested the Distorter with a Les Paul, a Telecaster, and Marshall- and tweed Deluxe-style amps, and very much enjoyed the pedal’s truly broad range of distortion tones—which offer much more versatility than the simple control panel suggests. Everything from dynamic, touchy-feely classic-rock and blues lead tones to savage and jagged heavy and stoner rock sounds can be summoned from this circuit.

Everything from dynamic, touchy-feely classic-rock and blues lead tones to savage and jagged heavy and stoner rock sounds can be summoned from this circuit.

Though the Double-Amp Distorter can be subtle, it still generates a fair bit of dirt at its minimum gain settings. And while it’s often reminiscent of ’70s and ’80s drive pedals like the MXR Distortion+ and Pro Co RAT, it’s still very much its own thing, with the ability to color relatively run-of-the-mill distortion tones with an appealingly ragged edge when you want it.

In audible terms, the differences afforded by the clip switch are often subtler than you might expect. That said, the switches can result in perceptible changes in feel, with the increased compression in the lower position and sharper attack in the upper position guiding your playing approach in constructive ways. The tone knob is subtle, too, in lower- to mid-gain applications, but there aren’t any offensive extremes in either direction. It’s very user friendly and the taper and range are mostly just right.

With gain wound up around 1 o’clock, the Double-Amp Distorter produces raw, heavy-rock voicings with a ’70s-inflected edge. Beyond those gain settings, however, the pedal verges on fuzz—with spitty, snarly, sizzling sounds and rowdily fun and loose picking dynamics that can be fine-tuned with the clipping control. In these high-gain ranges, the tone control is arguably more useful, shaping everything from thick, bovine, grungy voices to eviscerating grind. It’s thrilling, fun stuff that opens up a lot of performance possibilities.

The Verdict
While the Double-Amp Distorter might not be a first choice for guitarists seeking the hyper saturation of modern high-gain lead tones, it’s more than capable of fat, edgy, versatile drive that can move across broad expanses on either side of the RAT and Distortion+ realms. And though it’s a touch retro in its leanings, it also enables very artful and original dirt tones that won’t get you pigeonholed as a backward-looking purist.