In the last month or so I've played "Vintage Fuzz Roulette", a particularly expensive risk laden activity involving spending your hard-earned money acquiring something from the past that is possibly "mojo magic" or "absolute nightmare garbage"!
The Japanese brand/manufacturer ELK is not particularly delved into history wise and in recent years has for the most part gained attention via the ELK Big Muff Sustainar, a copy Triangle Big Muff with some changes. That Muff-copy unit has gained attention due to its use by Wata, guitarist from BORIS, a Japanese noise rock(?) group. A reissue in the form of the Earthquaker Hizumatus, and some others from Muff makers has followed. Originals are in the region of $500-$700, variously named on the Muff theme.
Since I have other ELK units, I've picked up what I can but the Muff, due to price, eluded me. Until last month when two came up at a more reasonable cost. Acquired, both quite different, Ying and Yang.
And finally, the specific BORIS font/graphic version popped up for a sale a few weeks ago. I watched, reviewed the comments. "No, we can't show the insides, because it is already packed". Hmm...how convenient! I thought. It sold and I forgot about it. To my surprise, a week later, it's back up on auction for half the price. "Junk", "I can't fix" it. Well, "in for a penny, in for a pound" as we Brits say. Popped in a bid, forgot about it.....and in the morning I had won....
And I laughed

It was either worst case, an empty box, Second - not what it seemed, or best-case scenario genuine but needed a fix.
Arrived last night, popped open the back, and this is what I saw..and heard...
Fascinating. It's clearly not the original circuit. But it's also a circuit that seems familiar, yet I can't put my finger on what it is exactly. To be fair I haven't sat down and checked component values, however it sounds very good, a crispy drive to semi fuzz/smooth distortion. There's an Op-Amp 1458 in there, an LED and a mystery silver box (cap?). Clipping diodes. But two batteries, 18v? It's not a modern PCB nor perfboard.
So, for a bit of fun, what do you think it is?
My initial guesses were some Distortion Plus variant, Kent Armstrong Blue Clipper, Boot-Leg Rock n Roll.. There were quite a few "Fuzz" pedals that used the op-amp type circuit in the 70s paired with clipping diodes.
Anyway, no real complaints, a cool box!