original Big Muff V1 components question

[eatyourguitar]

ok so I got this vintage muff pcb from peps1 on ILF (pigeonfx.com). I'm trying to make this as vintage correct as possible. I have been reading all the stories. skreddy says that the fs36999 were actually at least 3 or 4 different transistors that all got stamped with fs36999 and were sold cheap in bulk to those who weren't picky. so to make this clear fs36999 = any general purpose npn circa 1968. the first muffs were produced in 1971. it all makes sense. the diodes are documented also but extremely rare and no one even thinks it has a unique sound. so they all use 1n914 or 1n4148. I already have 1n4001 so i may put some diodes on a switch. the tranny's i plan to use are 2n5088. 239c and 249c seem to be common in later years. the real deal 2n5133 in the TO-106 package is pretty rare and probably doesnt make a huge difference.

my question is do you think its pointless to order carbon comp resistors and ceramic caps just for this project or should I use metal film resistors and poly film caps. also any thoughts on the trannys and diodes?

[devnulljp]

fs36999 is Fairchild 2n5133
I've had a shitload of muffs, and those trannies sound different to everything else.
FWIW, the Creepy Fingers triangle I had had socketed trannies and I ran it with a pair of 2n5133s and a pair of 2n5088s in the booster sections. Sounded great.

[culturejam]

Carbon comps might add a little extra hiss/noise, or they might not. Ceramic is generally cheaper than film, but I can't really say what kind of audible difference it would make. Some people swear ceramic sounds way different than film, but I'm not able to hear it (at least not conclusively).

I built a Muff that had values that were close to that in the Skreddy Mayo, and they sound very very similar. I used MPSA18 transistors in my Muff, and there ain't nothing fancy about those.

[McSpunckle]

The transistors in the Big Muff really aren't clipping that much, since their gain is so heavily limited by the clipping diodes and input resistors. I don't see how a different transistor would make a huge difference. The way they're biased, the gain of the transistor also won't make a HUGE difference.

IMO, it's the resistor and capacitor values that make the difference more than anything.

Some vintage transistors might sound different, though. I've never tried it. I use MPSA18s, just 'cause that's what I use for any NPN that doesn't need to be lower gain.

[nbabmf]

Most FS5133 are waaaaay too low gain, so you really have to measure them and go throigh a lot of them to find suitable examples. I'd just as soon use 2N5088/5089 and not need to buy a hundred trannies to find 4 good ones.

[eatyourguitar]

ok so I'm probably gonna just use 2n5088. I can get 200 for $13.99 shipped. I'm guessing that they are silicon. I'm buying a an atlas dca so testing transistors is no problem. I've heard people say hfe 200 is pretty average for a muff. someone tested 5133's until they had 4 in the 700 to 800 range. thats crazy high. any suggestions on where to get those 5133's? they come up on ebay once a year.

I've heard different theories on have 4 matched transistors or gains increasing with each stage. like 200,200,200,200 vs 190,200,210,220.

[devnulljp]

My favourite triangle had 2n5133s w/ hfes around the 7~800 mark.
But yes those cap values are really crucial.

[culturejam]

I'm guessing that they are silicon. I'm buying a an atlas dca so testing transistors is no problem. I've heard people say hfe 200 is pretty average for a muff. someone tested 5133's until they had 4 in the 700 to 800 range. thats crazy high. any suggestions on where to get those 5133's? they come up on ebay once a year.

Yes, 2n5088 is silicon. You won't need to buy an Atlas DCA in order to test them, however. Any regular DMM with a transistor test function will work just fine. The Atlas is great for germanium because it also measures leakage.

I'd shoot for anything with gain 400 - 1000. As McSpunkle pointed out, the biasing of the transistors is set up such that the gain isn't terribly important. I believe EHX did this so they could just use whatever part was cheapest at any given time. It's very smart.

I wouldn't worry too much about matching gains. As long as they are all 400+, I think you're good to go.