OnkartGromt Grombass And ZVex Mastostron

 IN ASSEMBLING THE PEDALBOARD of my dreams, I’ve found selecting a fuzz box most vexing; some are excessively noisy, while others can sound limp and soulless. When these two new fuzz boxes came in—the OnkartGromt Grombass and the ZVex Mastotron—I wasted no time parking them on my pedalboard and taking them for a tote around town.
By Brian Fox ,

IN ASSEMBLING THE PEDALBOARD of my dreams, I’ve found selecting a fuzz box most vexing; some are excessively noisy, while others can sound limp and soulless. When these two new fuzz boxes came in—the OnkartGromt Grombass and the ZVex Mastotron—I wasted no time parking them on my pedalboard and taking them for a tote around town.

GROMBASS

From the birthplace of fjords and a-ha, the Grombass is a new distortion unit from Norway’s OnkartGromt. The Grombass (rough translation:“fat bass”) is a stylish stompbox with three distinct distortion modes. A 3-way toggle switches between GERMNIUM, LED, and SILICON diodes (the electrical components that clip a signal to create distortion), arming the Grombass with a trio of fuzz sounds that range from mildly aggressive to meaty and massive. The GERMINIUM setting was the pedal’s mildest, adding just a bit of grit, while SILICON sat at the other end of the spectrum, imparting a sinister fuzz with less low end. My favorite sounds came in LED mode, which deliciously combined big bottom with sweet sizzle. In all three modes, the pedal operation was delightfully devoid of excess noise.

The cool-blue brushed metal box and playful black lettering gave the Grombass a somewhat whimsical vibe, and the pedal’s bright, beacon-like blue indicator light left no doubt when the effect was engaged. The 9-volt battery behind the Grombass’s back plate (secured by four screws) sat snugly inside the chassis throughout testing. It took a bit to get my head around the pedal’s GEAR and MUFFLER controls, but the MUFFLER is essentially a low-pass filter linked to the GEAR knob, which is a secondary gain control. I found it a little puzzling, but fussing with the knobs and switches yielded no shortage of cool tones. Though the Grombass costs a bit more than comparable stompboxes, its trio of fuzz sounds make the price seem reasonable. Add in points for style, and the Grombass becomes a sensible choice that working stiffs should be able to a-fjord.

MASTOTRON

Minneapolis-based electronics wiz Zachary Vex has earned a reputation for his small, somewhat quirky pedals, and can count all-star tone hounds like Trent Reznor, Nels Cline, and Jack White among his devotees. Zach’s rep seems certain to grow with the ZVex Masotron, a diminutive fuzz box with a few nifty twists. The pedal’s clever RELAX–PUSH knob serves to match an instrument’s pickup impedance. With both passive and active Jazz-style basses, the feature made it easy to dial in a sweet spot where the fuzz sounded tightest. The VOL, TONE, and FUZZ knobs functioned much as I expected, but the Mastotron’s SUBS switch and PW knob were a cool departure from the norm. The SUBS switch acts like a lowpass filter. For bass, the third position sounded thickest, but I could imagine using the others to great effect in the studio—on a song’s introduction, for example. The PW knob controled pulse width, blending from a square wave to a more jagged-sounding narrow-pulse waveform. From smooth and organic to rough and robotic, the pedal’s fuzz sounds were varied and colorful.

I loved the look and feel of the Mastotron, from its tiny footprint to its smoothturning, rugged-feeling knobs. After a bit of rehearsal to-and-fro, the pedal’s 9-volt battery loosened itself from its internal restraints. Such clatter threatened to batter the Mastotron’s tender bits, but a pinch of foam rubber made an easy fix. (ZVex responds:“We are addressing the issue with our production team, and plan to switch to a more robust battery fastener.”) Bottom line: the- Mastotron’s ultra-quiet operation and superscrumptious saturation transported me to a place of fuzz-fueled revelry where such minor irritants were no big whoop.

ONKARTGROMT GROMBASS
Street $270
Pros The LED mode’s smooth fuzz sound is a delight
Cons None
Contactonkartgromt.com

TECH SPECS
Power 9V DC or battery
Weight 14 oz
Switch True-bypass
Made in Norway
Warranty Two years

ZVEX MASTOT RON
Street $149
Pros Massive fuzz from a tiny box
Cons None
Contactzvex.com

TECH SPECS
Power 9V DC or battery
Weight 9 oz
Switch True-bypass
Made in Taiwan (circuit board), assembled in the U.S.A.
Warranty One year