Wednesday, 18 April 2012

Soulsonic - Folk Driver


Soulsonic's Folk Driver is a design I would have covered earlier - I just forgot I hadn't included it! It's a really great little low gain overdriver that Soul came up with after Bjorn of BJF presented a challenge to create a "Honeybee" overdrive work-a-like. Here's a quick description by Soul himself:

"Hi everyone, as I'm sure many of you know, Björn Juhl sent me a Honey Bee pedal to play with. The idea was to listen to the sound and see if it can inspire a nice DIY project. Well, after spending some time with it, I've come up with something that sounds good and will certainly remind people familiar with the sound of the Honey Bee.

My goal was to keep the design as simple as possible, but still try to fit in some tricks. This uses both positive and negative feedback to get its sound. R8 is something I learned from the big old red RCA book - it's positive feedback to boost the gain of the first stage; it was suggested as an alternative to using cathode bypass capacitor in a tube stage, well, it works just as well with a transistor. The combination of R9+C4 is negative feedback to reduce the high frequency gain and give the signature smooth sound. It also promotes stability in the circuit. I settled on the clipping diode combination after trying several different kinds, and the 1N4001+1N4148 combo had the best sound for this thing and reminded me most of the HB.

The Timbre control adjusts both the low-frequencies and the amount of drive. At the 12 o'clock position is the minimum drive amount. At one extreme it's max gain with lows emphasized, and the other is max gain with the lows cut. It's sort of like having the HB's Gain and Nature controls on one knob."

And a quick demo of the Folk Driver in action:


You can see how it's a subtle enhancer rather than a full on overdrive. This makes it great for stacking! Everyone loves to stack yeah?!

So, here's the schematic for you:

And a vero layout:


1 comment:

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