I found a chunk of vero just big enough for this puppy, and there is scant info on it and no youtubes. Looks like a silicon tonebender with some clipping diodes. That sounds like a LOT of fun!
Now THAT"S Italian!
Anyone do this one? It looks like it might be a sweet mod platform. A nice input cap blend, maybe put those diodes on a pot, etc...
http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/album18/album144/JEN_FUZZ_III_VERO_001.gif.html
http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/album146/FUZZ/JEN+FUZZ+GUTS.JPG.html
Awww, MAN! Nobody, huh?
I usually build the first versions, so I built the "Jen Fuzz"
(http://fuzzcentral.ssguitar.com/schematics/jenfuzzschem.gif)
which is very similar to the "III". It's actually closer to a Fuzz Face with an emitter follower up front and some clipping diodes. It's a killer, loud, trebly fuzz with very good sustain. I don't think I modded anything...
I asked 2 times on this forum for ballpark voltages or even guesses for this or a similar circuit, and noone gave anything.
I can only give you a few tips. One, don't worry about the "odd" voltages for Q1. I still don't know if it's typical for an emitter follower/buffer, but I got this for e/b/c:
Q1 > 5.96, 6.12, 9.04
Two, don't use high gain transistors. I found that's probably the #1 biggest error when building vintage fuzzes. I blindly used 2N5088's as called for in the schematic, but wound up with ones with much lower gains (~200), which sounded far better.
Three, changing the diodes didn't have too much effect...though, I can't remember if I tried germanium.
In the end I got close to what jmusser described:
http://www.diystompboxes.com/smfforum/index.php?topic=43036.0
good luck
andrew's build lists a 220 instead of the 22 ohm on above schem. the 220 ohm makes a lot more sense to me.
interesting circ, regardless. i always like to see early use of diodes to ground.
based on past experience and j musser's build notes, i would try to make the thing more gnarlee by reducing the feedback 150k to 68k or so, and increasing cap size at input and between Q1 and Q2. possibly a larger cap to ground in place of the 22u. instead of a fuzzpot, possibly a pot between the diodes and ground would add to the versatility.
Thanks guys!
Good suggestions, all.
John Lyons traded me for some transistors and now I have lots of low-gain silicon transistors for just such a project. They're the key to lots of old tones, and you don't have all this piggyback BS to deal with!
Quote from: superferrite on June 09, 2012, 11:46:15 AM
John Lyons traded me for some transistors and now I have lots of low-gain silicon transistors for just such a project. They're the key to lots of old tones, and you don't have all this piggyback BS to deal with!
you don't need low gains ones for these...just ones around 200 for Q1/Q2
http://transistor-spravochnik.ru/description/bc238b/23994
I should've noted that Q3 could be higher gain
http://transistor-spravochnik.ru/description/bc238c/23997
Just check your voltages...I got the best sound in the typical 4-5v range for Q3C
Spaseeba, tovarishch!
Built the 1st one, I think I used 2N3904's or maybe BC108's. Its loud, quite trebley with lots of sustain as noted- myself, I didn't like it much, found it harsh and unmusical and ebayed it on - its painted all black and stamped 'Stealth Fuzz' if anyone ever comes across it :icon_lol:
I'll probably build it tomorrow or the next day. I could always throw on a SWTC for a little bassiness.
Question: Did the fuzz pot do anything, or was it just for show like a Shin-ei FY2?
Quote from: superferrite on June 10, 2012, 06:11:13 PM
I'll probably build it tomorrow or the next day. I could always throw on a SWTC for a little bassiness.
Question: Did the fuzz pot do anything,
the attack is the same as on a Fuzz Face...and fully works
Quote
or was it just for show like a Shin-ei FY2?
??? not sure what you mean...the Fuzz pot in definitely not for show on both the silicon & germanium versions...
Hmm, my FY2 does "really fuzzy" to "REALLY,REALLY fuzzy"
Not a bad thing, just an observation.
Quote from: LucifersTrip on June 09, 2012, 03:55:26 AM
I usually build the first versions, so I built the "Jen Fuzz"
(http://fuzzcentral.ssguitar.com/schematics/jenfuzzschem.gif)
which is very similar to the "III". It's actually closer to a Fuzz Face with an emitter follower up front and some clipping diodes. It's a killer, loud, trebly fuzz with very good sustain. I don't think I modded anything...
I asked 2 times on this forum for ballpark voltages or even guesses for this or a similar circuit, and noone gave anything.
I can only give you a few tips. One, don't worry about the "odd" voltages for Q1. I still don't know if it's typical for an emitter follower/buffer, but I got this for e/b/c:
Q1 > 5.96, 6.12, 9.04
Two, don't use high gain transistors. I found that's probably the #1 biggest error when building vintage fuzzes. I blindly used 2N5088's as called for in the schematic, but wound up with ones with much lower gains (~200), which sounded far better.
Three, changing the diodes didn't have too much effect...though, I can't remember if I tried germanium.
In the end I got close to what jmusser described:
http://www.diystompboxes.com/smfforum/index.php?topic=43036.0
good luck
The emitter follower voltages look pretty reasonable. Ve "follows" Vb and is roughly half of the supply voltage. Guitar pickup signal is a few hundred millivolts to a volt so the bias is not crucial.
Metal can 2n2222's sound good for vintage fuzzes. They have low hfe.
Quote from: DougH on June 11, 2012, 09:17:28 AM
Quote from: LucifersTrip on June 09, 2012, 03:55:26 AM
I still don't know if it's typical for an emitter follower/buffer, but I got this for e/b/c:
Q1 > 5.96, 6.12, 9.04
The emitter follower voltages look pretty reasonable. Ve "follows" Vb and is roughly half of the supply voltage. Guitar pickup signal is a few hundred millivolts to a volt so the bias is not crucial.
at the time, what I thought was "odd" was that the voltages of the emitter and base were so close. I tried various gain transistors in that Q1 slot and the overall sound did change (not drastically)...and of course, the emitter & base voltages shifted up or down together, reamining almost the same as before.