Review: EarthQuaker Devices Aqueduct Vibrato

EarthQuaker Devices' Aqueduct delivers a torrent of vintage and modern tones that put a fresh spin on the age-old vibrato effect.
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True pitch-shifting vibrato is one of the oldest guitar effects, but EarthQuaker Devices’ new Aqueduct Vibrato redefines it for the modern age. Like its namesake, its a channel of watery goodness, allowing you to effortlessly conjure up liquid vintage vibrato tones, shimmering Leslie effects, modern synth-like warbles and even whammy-bar-style bends using the pedal’s various modes.

The Aqueduct has wide-ranging controls for rate and depth, as well as a dial for selecting from among eight modes: Sine, Triangle, Ramp, Square, Random, Envelope Depth, Envelope Rate and Envelope Pitch. Sine is smooth and subtle, delivering the familiar classic effect. Triangle, with its sharper rise and fall, is more pronounced, while Ramp produces a sharp downward bend, followed by a slower return to pitch. Square has the most abrupt pitch change and can be used to create trills as well as hammer-on and pull-off effects. Random, the most extreme mode, produces unpredictable seasick undulations as the depth knob is turned clockwise.

There are also three envelope-controlled settings in which your pick attack controls depth (Env D), rate (Env R) or pitch (Env P). With these modes, the rate and depth knobs take on new functions, such as setting envelope sensitivity. In Env P mode, depth acts as a wet/dry mix, allowing you to blend touch-sensitive modulation with your unaffected signal. The Aqueduct also features a silent footswitch that utilizes EarthQuaker’s Flexi-Switch technology, which provides for both traditional and momentary latching styles.


I found Sine mode perfect for creating classic-sounding vibrato — everything from subtle oscillations to swampy howls. Ramp mode’s waveform proved ideal for a rotary speaker emulation: With the rate control dimed and the depth set at 11 o’clock, it produced a gorgeously swirling Leslie effect. Triangle mode generated some excellent rubbery tones and its faster rise and fall can produce intense, even stomach-churning, pitch modulations.

Square mode, with its abrupt pitch shifts, proved to be a mind bender. At low depth settings, it creates a pronounced vibrato effect, but with depth at its maximum, the pitch alternates between a whole step below and a whole step above the note being played. It was especially cool to use in momentary mode, allowing me to drop in trills at will. The Random mode was also a blast for creating the effect of warped vinyl. Used at extreme depth settings in conjunction with a fuzz pedal, it made for a convincing simulation of an intoxicated 2,000-pound bee.

But it’s in the envelope-controlled modes that the Aqueduct really shines. The ability to increase the effect’s depth or rate with the intensity of my pick attack allowed for delicious layers of nuance. Env P is especially cool, as it makes whammy bar–like bends possible: Hitting the strings hard causes the pitch to drop and slowly return to normal as the strings continue to sustain. As with any envelope-controlled device, it helps to have hot pickups, but the Aqueduct responded well with both humbuckers and single-coils. With its versatile modes and the generous sweep of its rate and depth controls, Aqueduct delivers a torrent of vintage and modern tones that put a fresh spin on the age-old vibrato effect.


Aqueduct Vibrato


CONTROLS Rate, depth, mode selector (Sine, Triangle, Ramp, Square, Random, Envelope Depth, Envelope Rate, Envelope Pitch)
FOOTSWITCH Silent relay, true bypass, with momentary and traditional latching
POWER External 9-volt DC adapter
DIMENSIONS 4 3/4” x 2 1/2” x 1 1/2”

KUDOS Eight amazing vibrato flavors; a wide speed range; three envelope-control modes