SOLD WTS: Skreddy Hybrid Fuzz driver (Marc Ahlfs signature drive pedal)

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This is Marc Ahlfs signature drive pedal. He even discontinued the screwdriver for a short while because he thought this was the best one he made.

From the man himself:
"The Lunar's input is better suited for humbuckers and cleans up better with the guitar volume. I don't like how the Screw Driver's mosfet input sounds congested with humbuckers or how it darkens slightly when you clean up with the guitar volume. I designed the Screw Driver to not need the guitar volume for clean-up, and it was built using my Strat to achieve all it's target tones; in other words I make Pagey tones with my Strat -> Screw Driver, and I don't bother playing much with the volume knob when I play my Strat.

When you play a Les Paul style guitar, it's really part of the whole experience to adjust the volume controls to dial in the tone, and in my experience I generally have the pickup selector in the middle position and rarely have either volume knob full up.

The Lunar Module's input has zero headroom when using humbuckers. Great for fuzz, but not for cleans or overdrive (like it is with singles).

I love how the Screw Driver's hybrid fuzz (silicon -> germanium) section creates a proper vintage amp-like distortion with its soft edges and how it gets syrupy when you crank its gain, never harsh. And I love how the Lunar Module gets lots more fuzz and aggression and maintains a more neutral EQ rather than a jangly EQ signature like the Screw Driver (which certainly has its place, 'cause hey; variety is the spice of life).

So I started with the Lunar Module's input into the Screw Driver's output section and re-tuned it, both gain-wise and EQ-wise, to work with humbuckers (I'm using my Ibanez SZ520 with vintage Maxon PAF-style humbuckers, which is very close to a '59 Les Paul sonically and electronically) just as well as both pedals do with my Strat (that has Bill Lawrence L-280S noiseless singles).

Here is a list of changes:
- using Screw Driver's .047uf input capacitor instead of the Lunar's 10uf input cap
- limited the overall gain of the input transistor to give it more headroom
- changed the gain control of the input transistor from full-range boost to mid boost
- removed the high-cut from the bass side of the "tightness" control to retain clarity even when in bassy mode
- increased the series resistor on the bass side of the "tightness" control by a great deal so it doesn't overwhelm the fuzz section with boosted bass and excess volume when in bassy mode--instead just has a very natural sounding flubbiness at full counter-clock-wise and of course a tight, but not overly thin, response at full clockwise (much like the Lunar Module at this end of the range), and a neutral EQ at noon
- decreased the filter cap of the 2nd silicon transistor, by a bit, for better high-end clarity
- increased the output volume so that unity gain with loud pickups is still noon on the volume pot (with the Lunar it would have to be turned up to like 2:00 o'clock if I'm not mistaken)
- different output capacitor to match the openness of the humbucker's EQ when in bypass

So I ended up with the same clarity and touch sensitivity as the Screw Driver when using single coils has, excellent volume-knob cleanup, neutral and open EQ, and hotter range of fuzz available than the Screw Driver. Such a pleasure to finally be able to play with 'buckers and hear the same clear string attack and openness into a nice overdrive as it gets straight into the amp (better, even). And the fuzz sustains nice and liquid but not nasty sounding.

Okay, tried it with my Strat this morning.
It actually is a lot more Klon-like, very in the pocket with a nice mid crunch available in addition to the absolutely transparent tones available. None of the controls take it into over-the-top fuzz (humbuckers do get a lot more fuzz out of it than singles), but it's very responsive and still lots of power to tweak your sound. Just more polite and more mids-centric rather than boosting the full range of bass, which creates mush and havoc. The mid boost control is super yummy now and sounds awesome when you crank it as opposed to the "too much" that you could get previously when it was a full-range booster."


Excellent condition
Asking $290
Sms Nine seven 8 I eight 8 o O





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