Friday, September 14, 2012

Review: ZVex Mastotron

Review: ZVex Mastotron

Never has the name of a pedal more accurately described its sound. The Mastotron is a gigantic, prehistoric, hairy beast! And I mean that in the best way possible. With five knobs and one three-way switch, it has all of the tweakability of the Fuzz Factory without any of the unpredictability. It can go from a wall of fuzz to a quest of 8-bit video game synth sounds to a a medium overdrive to the meanest thickest bass fuzz you have ever heard.

The fuzz, tone, and volume knobs are self explanatory. It’s the other two knobs and the three-way  switch that hold the keys to the Mastotron magic. First, about that three-way switch, it’s labeled “subs,” and it controls the amount of low frequencies. Setting it on 3 will rattle the fillings out of your teeth, 2 is a nice middle ground, and 1 removes most of the low-frequencies and leaves you with a thin and cutting tone. The knob labeled “PW” stands for pulse width, all the way left is traditional square-wave fuzz, turned to the right is narrow pulses (the secret to those Nintendo tones). Finally, we have the knob for Relax/Push. This one adds source impedance to the incoming signal and “should be set fully clockwise when using passive pickups.”

Word on the street is that the circuit inside the Mastotron is very similar to the Wooly Mammoth. And I know that Jim James from My Morning Jacket is a big user of the Wooly Mammoth. I can tell you that using the settings in the picture above I was able to rock the lead part to Holdin’ On To Black Metal with a huge smile on my face. With these settings, you have a really rich and versatile fuzz tone that combines the best elements of a few classic fuzz pedals. It has the smoothness of a Muff, the wooliness of a good fuzz face and the attack and decay of a tonebender. Slight adjustments of the fuzz, PW, and tone knobs brings you varying degrees of those sounds.

Let me be clear though, it doesn’t sound like any one of those pedals. It’s more like throwing the three of them in a blender and playing through the results. Or maybe multi-tracking through each of them in parrallel and then blending the three together. It’s a best of all worlds fuzz tone.

But all of that is with the “normal” settings. Start moving the subs switch to the right or left and cranking the dial on the pulse width and you’re opening up a new world of fuzz tones. And that’s even before using (abusing?) the Relax/Push control.

I don’t know why the Mastotron brings out the dental analogies for me, but it does. Setting the subs at 1, the fuzz and tone full up, and the PW all the way to the right makes a sound that is like a dentist drill. It’s not a pretty sound, but it is effective for a part that you want to stand out in a mix. Leaving all settings the same and switching the subs to 3 brings us into serious video game territory. Using the neck pickup and rolling off the tone knob on my guitar had me rocking out to the Super Mario Bros. theme.

So there you have it, many flavors of fuzz in a small package at a pretty reasonable price. It's hard to go wrong with this one. 


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  2. Hi

    Great review!

    Does the volume change when subs are engaged - ie if I built one would it make sense to have the subs as a second footswitch with a toggle switch to choose 2/3 so that subs could be introduced mid song? If there is a drop in real or perceived volume this would not work but if it remained the same or raised in a boost-like way that would work

    Thank you

    1. The higher the number of subs, the higher the volume!