January 2, 2021 at 6:23 pm #16505
This is a Fuzz Face variant built on the PUFF v4 board with a few changes. I’ve tried these changes before on both the GBOF and the PUFF v2. In the earlier attempts the values I had for the changes weren’t correct and they didn’t work out well. This one is a nice crispy bacon fuzz somewhere between a civilized germanium and a loud aggressive silicon. Built on the PUFF v4 board this fuzz is blessedly silent except when asked to get loud and nasty. Changes made are R2 to 30K, R3 to 470R, R4 to 110K, C1 to .47u (wasn’t sure if this was correct so I socketed it), C3 to 47n, and C5 to 10u. The germanium transistors are an unidentified metal can with an hFE of 81 and a 2N1309 with an hFE of 111 – I have others I might try but I like these a whole bunch.
Here’s the face:
And the guts:
ChuckJanuary 2, 2021 at 7:43 pm #16508BarryKeymaster
Very nice, simple and elegant. Thanks for sharing!January 3, 2021 at 2:17 am #16512Dan BieranowskiParticipant
Love the clean design. What made you choose those mods?January 3, 2021 at 8:12 am #16513
Wish I could claim this as my personal genius and deep exhaustive research. A few years ago I read a lot of chatter about the London Fuzz. I liked the one audio demo I heard at the time. Initial online research showed the values I used except that C1 was listed at 4.7u with a later correction to the .47u – it’s easier to find the 4.7 schematic. Comparing my pedal with multiple current YouTube demos of the London Fuzz I can say this pedal is different – probably the magic is in the “unidentified metal can” in Q1 and that I bias by ear rather than with a multimeter.
ChuckJanuary 7, 2021 at 10:54 am #16547TJParticipant
Great build Chuck! Are those Lumberg jacks I see?January 7, 2021 at 4:41 pm #16556wilkie1Moderator
Nice work! Can you post an audio sample for us to compare?January 7, 2021 at 5:39 pm #16559BillyModerator
Great looking beast Chuck
I really like the enclosure knobs, labelling and the countersunk LED
I may give your mods a go I think I’ve got a PUFF somewhereJanuary 8, 2021 at 10:49 pm #16574
TJ – the jacks are Switchcraft #111X from Small Bear. They’re cost more than Lumbergs but are more solid. I’ve had some problems with the Lumbergs but none with the Switchcrafts.
Wilkie – I’m not set up to record well right now. I put most of my Fuzz Face style builds and a Roger Mayer Rocket FX Classic Fuzz on my board and tried to do an apples to apples comparison. These included a Shutone Fracas with BC108s, a Madbean Hipster with NPN Germanium AC130s (Q2 hFE is 120, had to cover Q1 with heat shrink to keep it from shorting), a Roger Mayer Classic (Early Version) built on the old PUFF v2 with 2N527s (hFEs are 81 and 115), a PUFF v4 with matched Russian Germaniums (a JB set) from Barry, and my London Fuzz-ish build on a PUFF v4. Set the fuzz pots close to the same (not quite all the way up) – except the RM Rocket FX Classic which has a bad drive pot that only works all the way up – then set the volumes to get roughly the same. Plugged in my home brew strat (Duncan SSL4s in the neck and middle and an SSL5 in the bridge; Super Switch gives me Neck, Neck/Middle, Neck/Bridge, Middle/Bridge, Bridge; middle pot is a Torres Mid Control and bottom pot is a master tone; also has a “Gilmore” switch with 22 and 47 caps for the tone) and started flailing away with the guitar volume at about 60%. Aside from the Fracas they didn’t sound that much different. The Fracas with it’s tone control and the 108s can sound similar to the Germaniums but wants to be loud with a real nasty edge to it (not always a bad thing), the Hipster with the AC130s sounds like a Germanium Fuzz Face (because it is) with a little extra noise (the board is designed for silicone trannies), the PUFF v2 Roger Mayer is a touch fuzzier than the Hipster and cleaner, the PUFF v4 with the JB Russians is more refined but just as fuzzy as the PUFF v2 Roger Mayer, with the fuzz/drive all the way up the two Roger Mayers are loud and nasty with the PUFF v2 Roger Mayer being a little more civilized and the LF sounds similar to the JB version with crispier edges but can hang with the RMs when the fuzz cranked with more mids coming through – but if I hit the strings too hard with the guitar volume way up it will tend to get honky/farty.
The PUFF v2 boards for 1590A boxes were neat and pretty much noise free but are kind of tough to use with tall skinny trannies in the smaller boxes, the PUFF v4 are are very quiet and easy to build – I’m going to need more since I’m not out of Germaniums just yet.
ChuckJanuary 11, 2021 at 1:28 pm #16617
I don’t normally revisit my own posts so often but I realized my long post comparing the different fuzz faces really isn’t very helpful. Thinking about it a little I decided to swap the transistors between my built by the BOM PUFF v.4 with the matched set of Russian germanium transistors and the modified version with the ball parked mystery and 2N1309 germanium transistors. The results were somewhat mixed. The BOM build sounded fine with the mixed set and the modified build did okay with the matched Russians but wasn’t all that impressive. Wheels started turning again – if lower hFE transistors didn’t sound as good in this build why not try some higher hFE transistors? Rooted through my stash of random stuff and found a pair of 2N404s with hFEs at 89 and 134. Popped those in (after returning the Russians to their proper place), tweeked the bias a little and all of a sudden I sound like Andy from Pro Guitar Shops (with arthritic, broken fingers)! Great wall of fuzz sound with lots of good solid, warm bass and good cleanup with the guitar volume with single coils. It’s a little dodgy with fake FilterTrons but I maybe just haven’t found the right combination yet.
ChuckJanuary 11, 2021 at 2:59 pm #16618wilkie1Moderator
A great review. Many thanks. I’m sure our readers will appreciate this.
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