Germanium Orpheum Fuzz (DATA DUMP)

[simonm]

Recent lucky uk ebay BIN!
Been looking online, not many pics of the Ge Orpheums, I can't get to the trace side of the pcb, but this one has a changed resistor and is super lound, splatty and horrible!









switch is marked UND LAB INC LIST, tone pot is marked PA811-2308



GE branded transistor is A405 (batch code 5T 1D SG imprinted on top), the other one is not branded but has the same type of batch code (5T 1C ER) - 5T could be '65?



logo is screenprinted, not stuck on.

[Lee]

Good stuff I really like the older odd ball fuzzes. I really wanna try building one

[simonm]

any idea who made it anyone? any chance it was mike matthews? I love the plywood sides!

There is a schematic for this online, but it has 6 resistors, whereas this only has 5 unless there's one hiding underneath, and one different cap value - this one has a ton of output and bottom end thanks to the mod, I think it's the 47K from the collector of Q2 that's been changed to 470K. It's doesn't sound much like a fuzzrite to me, though the circuit is similar - the clone in this video has a pretty close approximation of the sound http://youtu.be/VdJWv4emZdY?t=20m

I built the Si version about 10 yrs and was happy with it, but eventually the circuit was evicted and the box was used for another fuzzer -
vero layouts for both versions here
http://tagboardeffects.blogspot.co.uk/2 ... -fuzz.html, but pot values are wrong
see schematic at
http://web.archive.org/web/201310170756 ... uzz-Ge.gif

[rafmax]

There is a schematic for this online, but it has 6 resistors, whereas this only has 5 unless there's one hiding underneath,

About resistors, here is my Si version

FullSizeRender.jpg (104.68 KiB) Viewed 4467 times

FullSizeRender-1.jpg (117 KiB) Viewed 4467 times

[j behan]

Nice score Simon!

It looks like Q2's bias resistor from base to collector (1M) has been changed to 470k, which would not necessarily have much of an impact on the sound. We're not talking about finely tuned biasing here.
The two 47k resistors are there.

I don't see a second 22k (red/red/orange) resistor there, namely the one at the Tone pot's 3rd lug. If that's missing it would produce a louder, fatter sound. Unless it's under the board or something, like on Raf's Si version.
The 0.1uf caps would increase the low end somewhat, compared to the more common 47nf found in most Ge Fuzzrites, though a few early ones had 0.1uf caps too.

Btw, what's the value of that small dark orange cap? Normally it would be 5nf, which I presume is what the big ceramic is? They're usually 2nf in the Ge Fuzzrite, so they would increase low end also if they're bigger than that.

[simonm]

Raf - thanks for the tip (nice pics!) - the 2nd 22K is under the board, going from the tone pot to the ground lug of the vol pot.
anf Jimmy, you're right - of course it's the 1M that's been replaced, not a 47K! I still have to look up every resistor, colours swimming in front of my eyes, so failed to spot the 2nd 47K. Doh!
And the dark orange/red mylar cap is only 1nf, the big ceramic disk is 5nf, i think these are C4 and C5 on the analogguru schem, though he has them both as 5nf - so on that version of the circuit the tone pot wouldn't do so much.
Thanks!

[jerms]

that's a beaut' simon!!!... great score!! i'll post some pix of my mannys when i get home.... it's GE too.. it has the tone control..... got a few silicon ones too....

[simonm]

Cool - be interested to see the Manny's version properly - 3 knobs? same transistors?

[jerms]

here's my manny's.... pot dates 8th week of 68..... i guess these could be silicon...

[jerms]

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