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Z.Vex Distortron & Mastotron Pedal Review

The Mastotron and Distortron are two light-on-the-wallet, heavy-on-the-fx additions to Z.Vex''s lineup

The history of Zachary Vex Effects clearly illustrates how far unique ideas and personality can take an upstart company. His product line is mainly known for eccentric presentation with wildly creative paint jobs, the almost obsessive attention to offering minute control, and the ability to produce outlandish, unique tones that often inspire users to craft entire songs around them. His innovative designs (such as the Fuzz Factory, Wah Probe and Lo-Fi Loop Junky) have already achieved legendary status in the music world, and have influenced countless others to create designs that toil beyond the realm of normal convention.

One of the first three Fuzz Factories was snapped up by David Sylvian, and two Fuzz Factory pedals can be heard on 1999 on Semisonic’s hit “Closing Time." Vex’s work caught on quickly after that, when such legends as Billy Gibbons and Steve Albini promptly acquired his pieces as well. The Z.Vex name has since spread like wildfire, being featured on records and performances by Dinosaur Jr., Nine Inch Nails, Matte Henderson, Portishead, Johnny Lang and The Smashing Pumpkins, just to name a small handful.

In a world chock full of Tube Screamer clones, Z.Vex’s mission has always been to push the envelope of what an effect is capable of. However, as the company has developed over the years, more conservative entries have popped up for those who just want to rock. Both the Box of Metal (high-gain distortion and gate) and Box of Rock (moderate overdrive with boost) have been tremendously popular. While both fall into the well-populated distortion pedal category, they still exhibit the tremendous attention to detail and unique voice that the company has become known for. Joining these two moderately-priced pedals are two more, the Distortron distortion and Mastotron silicon fuzz. These two creations are not only the newest members of the Z.Vex family, but inaugural members of the new Vextron Series—designed for players with a smaller budget who still want to have a piece of the Z.Vex pie.

Download Example 1
Distortron: Vol 10 o'clock, Tone 1 o'cl, Drive 12:30; Subs 2, Gain Lo;
Download Example 2
Vol and Drive max, Tone 10 o'clock; Subs 3, Gain Hi;
 Egnater Tourmaster ch. 2 through Egnater 4x12" with Celestion Vintage 30's; Duesenberg MC Signature bridge humbucker; recorded in Sound Studio on an iMac using Digidesign MBox 2 (2 SM57s).
Hot on the heels of the supremely successful Box of Rock, the Distortron is a classic rock powerhouse in a compact pedal form. Vex describes it as “highly specialized to simulate the everything-on-ten sound of a classic Marshall JTM45 amplifier.” Like the Box of Rock, the Distortron is a different kind of departure for Z.Vex. It aims at achieving a time-honored guitar tone rather than a wild, off-the-wall sound. The decision to design this pedal shows off Vex’s love of the non-master volume Marshall heads of the past (beneath the mad scientist persona is a guitarist with a love of roaring British guitar tone). Achieving that sound with a classic Marshall is a relatively easy task; it’s also easy with the Distortron. The pedal consists of only three knobs: Volume, Tone and Drive. A tiny three-way switch to control the amount of Subs (subharmonics) sits between the Volume and Tone controls. This switch alters the amount of low end the pedal provides. In normal Z.Vex fashion, this control greatly affects the overall tone of the pedal. Position 3 is full-bore, representing the Box of Rock’s maximum Sub amount. Switching through 2 to 1 causes the tone to become noticeably thinner. This is especially helpful for amplifiers that naturally have large amounts of bass response, such as the 1973 Marshall Super Bass head that I tested the pedal with. In position 2, with a 2006 Gibson Flying V, it surrenders thick, articulate chords and a comfortable attack that is easy on the ears. Z.Vex suggests starting with the Drive control at the one o’clock position and adjusting to taste. The pickups in the Flying V are rather hot, but even at higher drive settings, the tone never muddied up and lost its articulate nature. One noticeable trait of the Drive is that when it’s maxed, the tone takes on an interesting nasal quality, but it’s not too overbearing to be annoying (at this point, it was practically begging for some classic Scorpions riffs).

After switching to a mid-90s Gibson Les Paul Studio with a Seymour Duncan ’59 in the bridge position, I dropped the gain control to 11 o’clock. Just like the Marshalls of yesteryear, the Distortron clearly shines with lower output pickups. Pick attack is much more evident, and sustain and decay are considerably more natural and smooth, with a great punch in the mids. Lowering the guitar’s volume control gives a terrific rhythm tone, with a clean upper register and growly midrange. Running the Distortron like this is really shows off how receptive it can be to pick attack, as it becomes highly sensitive to how hard the player smacks the strings.

The drive section also includes another mini-switch that sets the pedal to low- or high-gain modes with a simple flip. The “Lo” position is the standard Box of Rock level, and “Hi” gooses the gain stages for a slightly higher level. On lower drive settings, the effect of this switch is more noticeable; higher drive settings don’t offer as perceptible a dissimilarity, except when digging in harder with the pick to produce pinch harmonics and the like. Using the Distortron in high-gain situations sounds really, really good, but it sounds fantastic in low- to mid-gain applications.
Buy if...
you want classic rock tones in a touch-sensitive, articulate drive.
Skip if...
you need a more modern distortion sound.

MSRP $149 - Z.Vex Effects -

Hit page 2 for the Mastotron review...

Download Example 1
Vol 10:30, Tone 10 o'clock, PW max, Fuzz 4, Relax/Push max push; Subs 3 o'cl;
Download Example 2
Vol. 10 o'clock, Tone 1 o'cl, PW 12 o'cl, Fuzz 11 o'cl, Relax/Push 11 o'cl; Subs 2;
Egnater Tourmaster ch. 2 through Egnater 4x12" with Celestion Vintage 30s; Fender Road Worn Tele, bridge then neck pups; recorded in Sound Studio on an iMac using Digidesign
Stampeding through the speakers like the prehistoric animal its namesake implies is the aptly-titled Mastotron, Z.Vex’s powerful and rowdy silicon fuzz generator. The Mastotron has more in common with some of Vex’s classic creations, such as the Fuzz Factory and Wooly Mammoth, in that the tones it can produce range from a monstrous wall-of-fuzz to the soundtrack of a favorite 8-bit video game of yesteryear. A total of six controls shape the output of this beast: Volume, Subs (like the Distortron), PW (Pulse Width), Fuzz, and Relax/Push (source impedance). The three-way Subs control runs the gamut from huge, window-rattling low-end to a thin, reedy chirp. It’s a very dramatic difference.

Unusual and creative controls are one thing that has made Z.Vex’s products stand out in the past, and it’s nice to see that the Mastotron continues this tradition with two unique additions to its front panel. The first of these is a Pulse Width knob: a twist of this control allows the player to smoothly change the waveform from a full square wave (on the left) to narrow pulses (on the right). The last knob is labeled Relax/Push, and it adjusts the source impedance. Players with active pickups in their instruments often run into problems with over-compressed and unresponsive tones when using distortion and fuzz pedals. This is sometimes caused by active pickups producing a much hotter signal or a flatter frequency response than a passive pickup, which can lead to dull, squashed sounds. The Relax/Push control lowers the impedance as it is turned left, which Z.Vex says “softens” the input for active pickups. Those using the Mastotron with passive pickups are encouraged to max this control all the way to the right. With bass, this pedal is a certifiable monster. The low end stays super-tight and focused, and is somewhat reminiscent of Z.Vex’s bass creation, the Woolly Mammoth. Z.Vex also suggests that players try putting some odd effects in front of the Mastotron and playing around with the Relax/Push control to get unique sounds.
Buy if...
an inexpensive, tight fuzz with signature tone and lots of control is the name of the game. Bass players looking for a big fuzz tone should give it a whirl, too.
Skip if...
you need a more subtle, classic fuzz tone.

MSRP $149.99 - Z.Vex Effects -

The Final Mojo
As the introductory members of the new Vextron Series from Z.Vex Effects, the Distortron and Mastotron offer plenty of tonal options. For players who’ve been craving Z.Vex’s Woolly Mammoth bass fuzz, the Mastotron should provide more than enough punch, power and versatility for either bass or guitar players. For those leaning towards the classic rock side, the Distortron is an extraordinary tool for shaping the more articulate, nuanced guitar tones that genre commands, and it’s easy on the wallet at the same time.