Zvex - Fuzz Factory  [traced]

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Hides-His-Eyes
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Post by Hides-His-Eyes »

I doubt using low leakage russian Ges would cause a problem, but you're seriously saying you don't have any NPN silicon? 2n3904 is nothing special, anything will work (BC108/9, 2n5089 etc)
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Post by sinner »

Hides-His-Eyes wrote:I doubt using low leakage russian Ges would cause a problem, but you're seriously saying you don't have any NPN silicon? 2n3904 is nothing special, anything will work (BC108/9, 2n5089 etc)

Oh, I have a load of silicons, but usually with hfe higher than 400. AFAIK 2n3904 are 200 typically. I need to get 9mm pots so I'll get few 2n3904 from Banzai as well. Thanks :)

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Post by sinner »

One more shot - I guess using 5k6 instead of 5k1 won't change much?

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Post by mcaviel »

don't know if it change much but you can overcome this problem with soldering together a 3.9k- and a 1.2k resistor in series. :idea:
good luck with your build,
also i found out that my 2n2222 had higher hfe then 400 which made my FF to choke a bit and be less musical, it changed after i went with smaller hfe by replacing it to 2n3904.

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Post by TubeOrgasmer »

Renegadrian wrote:I shrinked that layout and built a couple so far - perfectly working, so go for it without fear...

Image
Just finished building this, however I think there might be a few errors on this schematic, or maybe it's just me, but seeing that I built it exactly as it is here I don't see how that could be the case. Also the AC128 aren't faulty because I've tried with a couple. My concern is the pot orientation. The volume pot shows very little response and ups volume when turned counterclockwise :scratch:
and the gate pot does what the volume should. Triple checked, didn't wire them wrong. I'm rather confused as to which schematic to follow as the two I've come across have some differences, with the pot orientation. :|

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Post by Krefu »

Just seeing this I must admit: In the original Fuzz Factory the STAB Control is a C5K (neg. log.). For those who like to use it Muse style, the taper makes a huge difference! The pitch control spreads over a huge range instead of just the last 3 mm of pod movement. And just for completeless (doesn't make a lot of difference) the volume pot is B2K.
briggs wrote:Why drink and drive when you can smoke and fly?

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Post by PrimateSynthesis »

I apologize if this is the worst question ever, but where can I find a regular schematic? I looked through dozens of pages of this thread, and saw some very nice builds, but the only schematic links I found were dead. Perhaps it would be a good idea to maintain the most relevant links in the first post?

Again, sorry if I'm looking in the wrong place.

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Post by PrimateSynthesis »

Ah, I found them in another thread. Sorry about that :oops:

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Post by hbwells »

if this has been answered before, I apologize. I couldn't find anything here after searching through 20 pages and no results from the search box.

Does anyone know the reason why the fuzz face can run germanium PNPs and have negative ground? Is it something to do with the 2n3904 transistor or something to do with all of the pots? It's driving me crazy trying to figure it out. Thanks in advance!

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Post by jb351 »

hbwells wrote:if this has been answered before, I apologize. I couldn't find anything here after searching through 20 pages and no results from the search box.

Does anyone know the reason why the fuzz face can run germanium PNPs and have negative ground? Is it something to do with the 2n3904 transistor or something to do with all of the pots? It's driving me crazy trying to figure it out. Thanks in advance!
It has nothing to do with the pots or the 2N3904. Just because a transistor is PNP it's not locked in only a positive ground circuit.
Jack Orman has a bit of a writeup on it here.

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Post by hbwells »

thanks jb! that helps a bit, but I heard there was some sort of decoupling cap or resistor (or combination for that matter) that had to be added to the circuit to ensure that no oscillation occurs. Any recommendations?

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Post by G5120fx »

I saw in briggs vero that you could substitute the Ac128´s with BC558´s.

Has someone ever compared these two types? I only have bc558´s at home and now I wonder if the tone changes dramatically with the germaniums. these little fuckers are really expensive if you buy a matched pair...

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Post by Scruffie »

G5120fx wrote:I saw in briggs vero that you could substitute the Ac128´s with BC558´s.

Has someone ever compared these two types? I only have bc558´s at home and now I wonder if the tone changes dramatically with the germaniums. these little fuckers are really expensive if you buy a matched pair...
It was me, I tested my original against one with BC558s in it and found it close enough, any PNP Silicon transistor should do though, 2N3906 etc.

Having said that, I wouldn't say you need to bother with matched germanium in this... some might disagree but I think with the pedal design and sounds, it really doesn't matter all that much.

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Post by poodlebra »

i've tried quite a few different gain combos of 128s and 2n404s, and i've found they do make quite a difference to how many 'usable' sounds you can squeeze out of this junk.

i prefer something around the 70-75 mark for Q1, and the higher end of the fuzz face scale for Q2 - 115-120ish

and my fuckers aren't that expensive, thank you very much. :wink:

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Post by Scruffie »

poodlebra wrote:i've tried quite a few different gain combos of 128s and 2n404s, and i've found they do make quite a difference to how many 'usable' sounds you can squeeze out of this junk.

i prefer something around the 70-75 mark for Q1, and the higher end of the fuzz face scale for Q2 - 115-120ish

and my fuckers aren't that expensive, thank you very much. :wink:
This thing has useable sounds!? :shock: :scratch: :mrgreen:

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Post by Alex Frias »

Well... I found a couple of dounds very usefull to me, but how to know if they will work for you? Very subjective matter. Anyway, if you look for something more "standard", better to stay far way from these one!

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Post by Scruffie »

Alex Frias wrote:Well... I found a couple of dounds very usefull to me, but how to know if they will work for you? Very subjective matter. Anyway, if you look for something more "standard", better to stay far way from these one!
:lol: I know that I was just messing about, there are definitley useable sounds... all though it can be a pain in the ass to find them some times.

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Post by G5120fx »

Sorry Scruffi for that mistake! I just found the vero on Briggs Blog, so I thought it was his idea...

Since I´m from Europe, I usually order my Parts @ Musikding (and for bigger orders I use Tayda).

So, Mr. Poodlebra I didn´t mean you ;) Don´t feel offended. Nice deals with the 3PDT´s :thumbsup:

And yes, I do think that 2,70€ + shipping is expensive for a Transistor, if you compare to a SI Tranny for 10ct´s. But that’s another story.

I have to take an order soon, so I order two AC128´s to see (hear) whats the difference.

Thanks for the replies!

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Post by LaceSensor »

I think the fuzz factory sounds good with silicon transistors but it doenst sound the same by my ears.

The factory de fuzz vero shown does work, Ive built it twice and it works fine.

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Post by poodlebra »

fac de fuzz vero def works, but it isn't clear that the middle pin of the comp pot needs to connect to the one on the left, what with the wires being different colours and it not quite curving right (hey, i'm a graphic designer - sue me!). to recap - connect the middle and left pins of the comp pot as shown on the layout. there. sorted. sorry, i've had beer :P

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