finding two matched sets of NKT275s

[mordechai]

I am trying to source out two matched sets of genuine NKT275s (not the phoney baloney ones available on ebay) for two Fuzz Face projects, and not having much luck.  I've got a bunch of other, good types of Ge trannies but I'd really like to make these two projects as close to the originals, with the original parts, as possible.  Any suggestions?  I tried Langrex but they don't have any in stock.

[midwayfair]

I am trying to source out two matched sets of genuine NKT275s (not the phoney baloney ones available on ebay) for two Fuzz Face projects, and not having much luck.  I've got a bunch of other, good types of Ge trannies but I'd really like to make these two projects as close to the originals, with the original parts, as possible.  Any suggestions?  I tried Langrex but they don't have any in stock.

I'm afraid e-bay is your only hope, though you could certainly post a WTB ad on all the forums. Go for the red dot ones and you'll be fine.

The originals used several different types of transistors -- so you can use easier to find PNPs to get "as close to the originals, with the original parts, as possible." RG Keen's article notes that AC128 was used in the earliest ones. Coincidentally, because they were such a crappy transistor and not much good for anything outside of pedals, there's still a lot of them around. I saw a couple matched sets on e-bay last night, and I was just looking for diodes, not transistors!

But it gets better. There are even new production AC128s. You can buy gobs of them cheaply.

[mordechai]

I actually have a bunch of old stock AC128s that are about 30-40 years old.  But if you read the Sunface info page on the Analogman site, Mike says that he has never seen an original Fuzz Face with AC128s.  Besides, I have tested several and honestly, to my ears, I didn't care for them.  In the FF type circuits I've been making, I typically use 2N404a's -- very low leakage and great gain ranges, and they sound terrific.  But I want to get as close to original as possible with these two builds, and therefore want to find the right 275's for the job. 

If all else fails, I'll use some Tungsram AC125s.  I can't say enough about those parts -- I LOVE them.  They work beautifully in Tonebenders but I have used them in FF circuits and they can go from woolly to raspy to smokey to smooth really easily with the bias adjustment.  If I wasn't trying to be as true to 1967-ish specs as possible, I'd use them as my first choice.