The Black Acid is basically a fuzz face clone (circa 2012). It is a pool of thought and ideals. All the little iddy biddy nuggets of information learned from screwing around with this circuit over the last 10 years. Nothing revolutionary and no reinvention of the wheel just a different slice of the same cake.
The destination on the trip: The Black Acid has substantial weight and heavy saturation without having a complete strangle hold on the lower frequencies. It has the same perceived amplitude as the old Meathead Dark but with the lows being tighter with greater clarity. It has considerably more output than a stock Fuzz Face but I'd say that it retains more of the vintage nature than any of the Meatheads, I guess you could say the frequency spread is more even. The highs and lows are nicely balanced so the projection is good plus with the mids not being as forced the clean-up from the guitars volume control is very pleasant, though pleasant wasn't really plan here.
The construction style and the internal arrangement is the same as with the Priest. A much simpler circuit with components specially selected to get the job done. At the heart of the Acid is a pair of Magnatec BC109's. UK made transistors don't you know. A great quality component that really complements this circuit set-up. Even running flat-out and blowing the barn doors wide open there is cleanliness or crispness to the tone. Don't get me wrong, it's as sludgy as fuck but sludgy without having cotton wool forced into your ears.
The controls are pretty damn obvious but I'd say the rule of attenuation applies to this pedal, as in I'd advise starting out with the Drive and Fuzz controls wide open and them bringing them back to where you'd like be at. The Fuzz is as you'd find on any Fuzz Face or the Tone Benders Attack control, it's only really gonna kick-in with the heavy on last quarter of the turn. There be plenty of scope for cool tones and amp blending but if you want the heavy open it up. The Drive is basically the pre-gain of the pedal. It's like having your guitars volume control on the floor. The point of this is that it's a great way to un-flab the lows when you're driving the thing hard into the front end of a driven valve amp. It also gives up some great overdrive tones and just makes the box a whole lot more of a flexible tool. The Drive and Fuzz controls also have a pretty sweet interaction thing going off. The Black Acid ain't as 'yeah! lets fucking party!' as the Priest is on the controls front but put the time in and the rewards will be plentiful.