Dating fuzz faces
As time wore on Germanium transistors were slowly being phased out in favour of the more stable and consistent Silicon versions, as a result Dallas-Arbiter began equipping the Fuzz Face pedals with these new transistors from 1968 onward with differing results.They do sound different from the original Germanium versions usually with a more harsh and aggressive clipping as opposed to the "soft" clipping characteristics of Germanium.
This is to be an exact copy of the Arbiter Fuzz Face pedal, this pedal is as simple as it gets with just four resistors three capacitors two potentiometers and two transistors. This was used by pretty much everyone in the late 60's and onward like Jimi Hendrix including David Gilmour (there's a pattern there isn't there) The first Fuzz Face came out in about 1966 and was powered by a single 9v battery with 2 matched germanium transistors, there were at least three types used NKT275 AC128 and SFT363E. The original germanium Fuzz Face has a warm fuzzy distortion that is easy to tame.
Even the new reissues are over £120, which I think is criminal for what's in it... Especially when they call one model the "Jimi Hendrix Fuzz Face" obviously that's going to cost more at around £170..... The rest is just my time, and enjoyment at creating something i can say "I did that"....