Mad Professor Simble Review

IMG_0004Having just explored the Dumble territory with the rare Dumbbell pedal, I was intrigued to find that Mad Professor Simble came up in my PedalGenie queue.  This is one of the newest and a well-respected entry in the playing field.  How does it stack up?


This is a four-knob overdrive but instead of my preference of gain, treble, bass and volume, this one sports unintuitive names lie Sensitivity, Contour and Accent.  I am assuming that the knob names were inspired by the amp it is trying to emulate but for the sake of user experience I would prefer to call Sensitivity gain, as that is what it is — the amount of overdrive.

Sensitivity can go all the way to clean, but you’ll have to compensate for the reduced volume by turning the Level up.  Until about 9 o’clock the pedal is totally clean, so you can use this as a clean boost.

Accent and Contour are interesting, in that the former controls treble pre-gain, while the latter is a post-gain treble control.  What this allows you to do is to really taylor the texture of the overdrive — from warm and woolly or bright and fizzy.  You choose your sweet spot in terms of the tone, and then use the Contour fine tune the overall brightness.  In real life this is a bit confusing, but once you understand how each knob affects the tone you can start to dial the right sound.

One other thing — this pedal features a relay-based true bypass, so the footswitch has that soft action, not the hard “click.”   It feel very nice.


Feel, feel, feel!  I feel like I focus on this quite a bit lately, but it is a major factor to consider.  How does the pedal respond and react to your playing?   In Simble’s case, it feels very natural, organic and dynamic.  I was floored by Dumbbell’s stupendous dynamic response, but Simble can hold its own in that department.  Very impressive.  The difference between soft and hard picking still results in a big change in both dynamic and the amount of overdrive.  If you have a good command of your touch, you’ll really enjoy the expressiveness that comes from being able to vary the tone based on your articulation.

With two knobs dedicated to sculpting the treble, this pedal can get rather bright when cranked, and harsh if both Accent and Contour are turned up.  That may be unexpected when you associate Dumble with dark and smooth tone.  My guess is that you’ll end up either setting both tone knobs around the middle, or have one up and then the other down to compensate.

What you can’t dial out is the woolly and hair low end.  I have never played the real thing so I can’t comment, but this fat low end must be one of the signatures of the Dumble tone.  It sounds quite nice on single-note lines, but just like Dumbbell it seems to muddy up in-between settings for a Strat, and on a humbucker guitar low strings may be overwhelming — the only way to somewhat compensate for that is to make the tone bright, which will help in the articulation department.  My belief is that pre-gain bass and post-gain treble (the famous Timmy configuration) gives an overdrive/distortion the biggest tonal range with the minimum number of knobs.  I wonder if the bass was rolled off the pedal would lose some of its signature Dumble-ness, but I do believe it’s more practical.


If you think a factory manufactured pedal can’t attain the level of dynamics and responsiveness that hand-wired pedals can, then you’ll have to think again with Simble.  Its dynamic range is so huge that you just feel like you plugged straight into a tube amp — it feels great for rhythm playing, and euphoric if you’re a lead player who rely on touch sensitivity.  But its squishy and woolly low end and the inability to dial it out robs some versatility or transparency.  I would say this pedal is worth checking out if you’re looking for a smooth mid-gainer in classic rock/blues/jazz type situation and warmth, smoothness and dynamics are more important than tightness and compression.

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