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3 Leaf Audio Proton Envelope Filter

Issue #10

Dan Veall was so carried away with 3Leaf's GR2 (reviewed in issue 9) that we gave him another from the Seattle wonders, just to watch his little red eyes light-up with joy!

After the fun I had with 3Leaf's GR2 in our previous issue I've been given another of the company's envelope filters to try this time, but this one based on another legend of the Funk world. I'm pretty sure 1970s Funk and Soul music wouldn't be the same without this characteristic sound. A bit of Bootsy anyone? Stevie Wonder and Jerry Garcia, amongst others, also helped make the Mu-Tron III envelope filter famous. Mu-Tron's beast of a pedal was another that ate up pedal board real estate and didn't make life easy for guitarists, as it needed its own special power supply (and a suitcase to house it in!). Spencer Doren of 3Leaf Audio has taken the design of the Mu-Tron and in his view improved it, as well as treated it to a serious diet. Once again, he has managed to squeeze a beast of a box in to a small case. In fact, this time it's even smaller than the GR2 Groove Regulator.

The fewer controls of the Proton in comparison to the GR2 certainly does not mean there is any less flexibility in terms of available sounds, though. In fact, the Proton, like the GR2, is packed with useful and epically funky sounds!

I feel the sign of a great boutique pedal designer is to know what features are needed and useful while not 'over-cooking' things unnecessarily with too many bells and whistles. This could also be said about great amplifier manufacturers. Cluttered knob layouts lead to confusion. Most bass players like to keep things relatively simple, I think, and for that reason the Proton will be welcomed with open wallets - simplicity, ease of use and overall great sounds!

Like the GR2, the top left control is the 'sensitivity' but on this model it is labelled Gain instead. I think I prefer that as a name as it is controlling the level in to the filter circuit. Too low a level and the filter won't affect the signal. The Proton doesn't have the attack and decay controls of the Groove Regulator, however adjusting the Gain control does affect those functions as you advance the knob clockwise. Experimentation is needed to find that point on the dial that nails the sound you are after. Again, like the GR2, switching to a bass with a different output level may mean that you'll need to readjust this control.

To the right hand side is the Peak knob - this could be described as the effect resonance, or the 'depth' of the effect. I found that lower settings were subtle and much higher settings delivered an effect that would cut through any band mix. In some cases a few ear drums too! I'm sure this would have sounded fantastic daisy-chained with a distortion pedal connected after it (placing a distortion pedal after a pedal that relies on signal dynamics instead of before will ensure a stronger effect from the dynamic pedal. Distortion pedals compress the dynamic range on higher gain settings so if placed before can mean that the dynamic effect is subdued.)

Three switches below the two knobs include: Range, which controls the frequency range of the filter sweep - great for using with either bass or guitar, you can switch to the range that has the strongest effect or indeed, whichever you prefer! Moving on to the range switch, which again, like the GR2, toggles between a band pass mode that focuses the effect more aggressively in a specific region but loses low end. Or there is the low pass mode that allows low frequencies through the pedal as well so that the signal remains full. There's nothing worse than disappearing from a mix, swallowed up by the volume of other instruments when your low end disappears! The last switch on the front panel reverses the direction of the sweep effect. 3Leaf Audio suggests raising the gain control a little to make the effect more pronounced.

Having both of these pedals in at the same time for review was pretty exciting and I am pleased to report that they delivered signature funky tones. It was easy to get great sounds and I feel that even a novice to envelope filters would be grooving very quickly with either of these models.

Which one is for you? Well watch the video here and check-out iGuitar 9 to hear the GR2! To me, both are fine boutique pedals and which you choose will depend on your ears.

Issue 10

Issue #74

Jim Root

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