So I've been looking at the EQD Black Ash / Carbon Black Fuzz. EQD even posted some pretty gut shots of the real thing on their website - looks like a couple paper in oil 0.1nF, axial 4.7uF, some sort of polymer/film 2n2uF, and a bunch of 1/2W carbon resistors.
... so has anyone ever built one up with vintage bits vs. modern? Any difference? Or do I need to do something "for science"?
But... but... MOJO... Or, more likely slightly out of spec high capacitances... I do hear a slight difference between my "modern" Thagomizer and my "vintage" ones, but when I measure the tropical fish capacitors they tend to be a sneeze high...
I love this quote from Brian Neunaber (of Neunaber Audio, and who I've just recently learned was the designer of the Belton Brick!):
"While music is art, audio is a science that is understood. It is not black magic."
Vintage "Mojo" is poor parts tolerance leading to distortions that may or may not sound subjectively better to a certain listener's ear, and for every unit that has 5 more "Mojo" points than an average "good" unit, there's another unit that has 5 fewer "Mojo" points than an average "good" unit.
If you build with NOS parts, you either a) build with what you have (like they would have back in the day) and are just as likely to build a unit with fewer "Mojo" points as one with more, or b) you're gonna measure the parts to make sure they're within tolerance, and at that point could have just built with modern components anyway.
(And I really like the stock "Top" control myself with my setup, doesn't do much to the overall character of the fuzz but it's more like a targeted presence control)
It stands to reason that in a world where a company like Vishay is making elegant and aesthetically pleasing < 1% tolerance MF resistors and, wait for it....1% Axial Film caps, that 60s engineers would bitch slap us if they found out we were using old drifted components to make circuits.
I think real engineers would laugh at anyone ascribing any sort of ‘magic’ or ‘mystical’ properties to electronics.
EDIT: To be clear, non-characterized specifications are not the same as ‘mystical’ characteristics. The former is certainly the case—as materials, construction, layout all affect a circuit. It’s just quite rare that some of the purported characteristics ever come into consideration with low-voltage pedals circuits.
Carbon comp resistors are prone to cracking with age, and are prone to humming and buzzing. Different capacitors do have a very large amount of difference in circuits with 400v. I have a "foil end" tester that is simply a couple of alligator clips in the signal path with a switch to change the polarization.
Using it, you turn the amplifier on, and induce a noisy EM source like a motor or neon light. When you switch back and forth the buzzing from the noisy EM becomes quieter when the foil end is on the side with the least amount of impedance.
It is almost impossible to determine the foil end on a paper in oil cap because they are so quiet. Sozo's buzz like freaking crazy to the point that it's so noisy that it's hard to tell which side is the foil end.
Carbon film resistors have a warm tone extremely similar to carbon comp but without the buzz and are used in signal paths where metal film are used in non signal paths.
Again, this is in extremely high voltage applications, not very low voltage applications.
I'm sure many of you have looked at gut shots of vintage amps, nuff said. Those resistors and caps where used after extensive double blind tests for their tone, not their science.
One of the 5E3's that I built was getting run away oscillation when I would turn the volume up.
When chop sticking it, hooked to an oscilloscope, I watched that wave form go from a box full of squiggly lines to a perfect wave when I moved one wire. I could actually change the breakup on the amp by moving this one wire to different positions. Which is probably why no two 5e3's have the same sound (and also since they don't have a NFB circuit.) You can see the position of the blue wire that I settled on for the frequency response to my ears.
I have a friend that designs capacitors for the military for things she can't even tell me about. The shape and material of the capacitor are used for various applications she can't tell me about. If there were no difference between them she wouldn't not have a job that she can't tell me about.
On the other end of the "vintage mojo" subject, I met Leo Fender when I was a teenager, he was talking to Les Tuttle who was my friends dad. Les used to test Leo's designs and provide feedback since Leo didn't play guitar. They grew up together as next door neighbors. Leo was talking about how people were cloning his designs and even using the same cloth wire that he used. He said "I only bought that crap because I got a zillion feet of it for practically nothing".
3903s are out-of-production/old stock and I think their limited availability was the reason the black ash was a limited thing. If memory serves the ad copy rationale for the carbon resistors was along the lines of "since this was going to be limited we figured we'd put some other old junk in it too."
It's entirely likely that I'm remembering incorrectly... I remember having to scrounge a bit to find the 3903s but that might just mean that neither Tayda nor my local surplus place had them.
It's entirely likely that I'm remembering incorrectly... I remember having to scrounge a bit to find the 3903s but that might just mean that Tayda didn't have them.
3903s are out-of-production/old stock and I think their limited availability was the reason the black ash was a limited thing. If memory serves the ad copy rationale for the carbon resistors was along the lines of "since this was going to be limited we figured we'd put some other old junk in it too."
"It uses a highly curated cache of rare and irreplaceable components including paper-in-oil capacitors and NOS half-watt carbon composition resistors from EQD President Jamie Stillman’s personal stash"
the transistors weren't the "scarce" part, the resistors and caps were, and not because the values are rare, just because they're old.
Exactly, which makes the rationale of using CC resistors in guitar pedals snake oil.
I'm sure many of you have looked at gut shots of vintage amps, nuff said. Those resistors and caps where used after extensive double blind tests for their tone, not their science.
"extensive double blind tests for their tone" IS science. Like, almost the definition of.
(and the odds are *very* high that once values were settled on, a *lot* of A/B testing was done between brand A and slightly-cheaper-brand B to determine if going with A made enough difference that going with it over B would be worth it. Because a solid chunk of engineering is building to cost.)
(and of course that's how modern amps and pedals are designed too, just with parts with significantly tighter tolerances leading to less variation when produced in high quantity.)
Or, more likely slightly out of spec high capacitances... I do hear a slight difference between my "modern" Thagomizer and my "vintage" ones, but when I measure the tropical fish capacitors they tend to be a sneeze high...
