Aphex Xciter Pedals

By Michael Molenda If you’re a studio hound, then you already know that Aphex is one of the top dogs of psychoacoustic processing. In 1975, the company freaked out record producers and engineers with its Aural Exciter—a transient harmonics generator that enhanced the minute sonic details of sou

By Michael Molenda

If you’re a studio hound, then you already know that Aphex is one of the top dogs of psychoacoustic processing. In 1975, the company freaked out record producers and engineers with its Aural Exciter—a transient harmonics generator that enhanced the minute sonic details of source sounds. Whatever went into this magic box not only came out sounding more vibrant and more present, but the signals also possessed an airy, sensual sheen that catapulted vocals and lead instruments far above the mix. Not surprisingly, just about every major-market record utilized the effect to some extent, and, even today, Exciter processing is arguably the most “organic” method for escalating harmonic grooviness.

In 1990, Aphex shook up the studio world once again with its Big Bottom processor. Big Bottom offered a way to produce massive rumble without cranking up power requirements (as bass players know, it takes a hunk o’ watts to produce studly lows). This process has been quite a boon for those producing dance music, movie soundtracks, video-game sound, and rock albums for downtuning guitarists. Suddenly, bass signals become deeper and more resonant at practically all audible playback levels.

But, until now, Aural Exciter and Big Bottom technology has seldom ventured outside the studio. Aphex’s new Guitar Xciter and Acoustic Xciter pedals ($199 retail/$149 street each), however, put both processes right underfoot. And, trust me, you’ll dig how these babies can energize, invigorate, and intensify your fave guitar sounds.

Box Talk
The pedals themselves instill immediate confidence. Although Aphex is traditionally a studio-
oriented company, it’s obvious its designers understand how evil and destructive the gigging grind can be. Here, the technology is enclosed in a rugged, aluminum casing, and all switches and knobs are battened-down and road tough. (Although the front-mounted mini-switches that select passive/active, ground/ground lift, and wet/dry source are susceptible to being pushed in if the pedal moves against a power cord, monitor speaker, or other such obstruction.) The pedal’s four rubber feet are pretty solid, as well. I banged the bottom of the pedal against stairs, road cases, and splintered wooden stages, and couldn’t knock off even one foot.

A top-mounted LED illuminates whenever the pedal is active, and bold white lettering on a black background ensures that knob tweaks can be easily addressed in low-light situations. Power is supplied by a 9-volt battery (accessed by unscrewing four Phillips screws on the pedal’s underside) or an optional power adapter. As with most pedals, battery power starts draining the moment you plug a cable into the input jack. (Aphex estimates that you can expect 100 to 150 hours of use from a fresh alkaline battery.) There is no discernable sonic difference between using a new battery or AC power.

Guitar Xciter
I tested the Guitar Xciter with a Les Paul, a Strat, and a Guild X-160 hollowbody, and ran each guitar direct into a Mackie 32•8 mixer, as well as through a Marshall JCM 900, Carvin’s Vintage 16, and Hughes &Kettner’s Warp 7 combo. This Xciter pedal is voiced from 40Hz-210Hz for the Lo Tune (Big Bottom), and from 500Hz-5kHz for the Hi Tune (Aural Exciter). You can select each process separately—or use them in tandem—by simply twisting the respective Lo or Hi Blend knobs to 0 (off) or anywhere from 1-10 (on).

Going for the Hi process first, I set the Blend at 5, and began auditioning the range of the Hi Tune knob. (First impression: You can get some hip filter sweeps by rocking the knob back and forth.) No matter which guitar I used, I was able to find a frequency setting that added subtle sparkle and airiness. And when I added a maxed-out Pro Co Rat distortion pedal to the mix, the Xciter made it easy to increase note articulation without resorting to severe—and somewhat unnatural—EQ tweaks.

In a similar test with the Lo process, body resonance and thump was magnificently enhanced for all guitars. The coolest application, however, involves using the Hi and Lo controls simultaneously. The sonic spectrum of your guitar seems to expand into the stratosphere, as the Xciter bestows warm, chunky lows and ethereal highs. Note attack can be somewhat sharpened or muted with the Tune knobs, and facile tweaking absolutely intensifies kerrang, thump, shimmer, and punch. One warning: Unless you’re into feral noisemaking, I’d recommend caution when using the Blend knob, because you can definitely enhance a guitar’s “bad” qualities (gronky mids, buzzy treble, etc.), as well.

In all cases except the most extreme, however, the Xciter effect sounds very natural—there’s no obvious sense that you’ve tweaked EQ knobs to dial in a tone. I even tried to replicate the pedal’s tonal enhancements with mixer EQ adjustments. While the basic character of the sound could be approached, boosting frequency bands couldn’t match the dimension, shimmer, and “wide screen” quality of the Xciter processing.

Acoustic Xciter
The acoustic side was represented by a Martin ALternative II (with a Fishman Prefix Pro system) and an old thinline Kramer Ferrington. (Direct tests were the same as above, but I used the Genz Benz Shenandoah for the amp test.) The Acoustic Xciter’s voicings are 40Hz-210Hz for the Lo Tune, and 300Hz-3kHz for the Hi Tune.

Again, the most smashing effects were attained by using the Lo and Hi processes in tandem. A few Lo tweaks really helped expand the resonance of the Kramer, and I was even able to calm some of that guitar’s piezo spittle with the Hi Tune. The bigger-bodied Martin sounded tremendous, with a thick, blossoming low end and heavenly highs. And, if you don’t have an acoustic amp, the Xciter can really open-up the sound of an acoustic played through a conventional guitar amp. Of course, hitting the Blend too hard on the Hi Tune brings out string squeaks and fret noises—and getting too nuts with the Lo settings exposed body thumps and feedback rumbles—so subtlety is the key for the best results.

X Factors
I’m enraptured with anything that helps guitars rage, roar, and jump off the bandstand (or leap out of stereo speakers), and these pedals do the job. If you’re looking for a tone that goes to “12” or “13” instead of “11,” then get Xcited.