The Emanating Fist Electronics Black Acid is a fuzz pedal, subtitled the "Tone Distorter," that the maker describes as basically a Fuzz Face clone dating from around 2012. Its aim is a heavy fuzz that does not lose the bottom end: the maker describes it as having "substantial weight and heavy saturation without having a complete strangle hold on the lower frequencies." It sits in the same family as the Dope Priest and the Black Dust, sharing the Priest's construction style and internal arrangement1. For more fuzzes of this type, see the site's guide to Fuzz Pedals.
Sound and circuit
The Black Acid is the work of the captain of Emanating Fist Electronics, drawing on what he calls "all the little iddy biddy nuggets of information learned from screwing around with this circuit over the last 10 years." Compared with the old Meathead Dark from the same designer, it has the same perceived amplitude but with the lows being tighter and with greater clarity1.
At its heart is a pair of Magnatec BC109 transistors, UK made. Builders on the layout page have tried substitutions with good results: one found it "sounds awesome with high gain (about 160 and 295) 2N404As too," and another suggests BC549 or BC109 transistors with hFEs close to 300 and 500, saying that with careful biasing "this thing just roars, perfect for heavy riffing"1.
Controls
| Control | What it does |
|---|---|
| Drive | Sets the pre-gain of the pedal, like having the guitar's volume control on the floor; un-flabs the lows when driving a valve amp and can give overdrive tones1 |
| Fuzz | Fuzz amount, interacting with the Drive control1 |
The maker advises a particular way of setting the two knobs: "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 two controls have what the maker calls a sweet interaction, and this starting-wide approach is described as the rule of attenuation1. One builder on the page suggests the Drive control works as an input cap blend, and that a C1k (audio taper) pot works better for the Fuzz control than the linear pot, which he found useless around 80 percent of rotation1.
What builders said
The page's comments come from hobbyists who built the circuit from the published stripboard layout, so their reports are about the build as much as the pedal:
- Mulekicker, using BC109B and BC109C transistors: "Done. Sounds great, no gating in the note decay like my meathead. Great OD when guitar volume is rolled back." He also found the Drive knob adds or subtracts wooliness1.
- AlexS, comparing against his Meathead Deluxe clone: "Similar feel, but the tone is different like it says on the description"1.
- Craig, built stock to the layout with BC109B/C: "It sounds great... but the volume seems a bit weak"1.
The Black Acid is a small-run pedal from a boutique maker. The published layout dates from May 2017, and the reports above come from builders of that layout rather than from factory production units, so transistor choice and biasing make a real difference to the result1.
Videos
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Questions
Is the Emanating Fist Black Acid a Fuzz Face clone?
Yes. The Black Acid is described as basically a Fuzz Face clone, dating from around 2012, but developed by Emanating Fist Electronics over roughly ten years of working with the circuit. It is a Fuzz Face-style fuzz that aims to keep substantial weight and heavy saturation without strangling the lower frequencies, and it shares its construction style and internal arrangement with the Dope Priest.
What transistors does the Black Acid use?
At the heart of the Black Acid is a pair of Magnatec BC109 transistors, made in the UK. Builders have also reported good results with substitutions: one builder found it sounds great with high gain 2N404A transistors of about 160 and 295 hFE, and another suggests BC549 or BC109 transistors with hFEs close to 300 and 500, along with careful biasing.
How does the Black Acid compare to the Meathead?
The Black Acid is related to the Meathead Dark and the Meathead family by the same designer. It has the same perceived amplitude as the old Meathead Dark but with tighter lows and greater clarity. One builder who tested it against his Meathead Deluxe clone found a similar feel but a different tone, and another noted no gating in the note decay, unlike his Meathead.
How should the Drive and Fuzz knobs be set on the Black Acid?
The maker advises starting with the Drive and Fuzz controls wide open and backing them off to taste, a rule of attenuation, because the two controls have a sweet interaction. The Drive is the pedal's pre-gain, like having the guitar's volume control on the floor, and it can also produce overdrive tones when driving a valve amp.
Sources (1)
- Guitar FX Layouts: Emanating Fist Electronics Black Acid, Guitar FX Layouts (tagboardeffects.blogspot.com), 2017-05-07
