Monday, 28 April 2014

Bearfoot Candy Apple Fuzz Gold

There was a resistor missing from the schematic so the layout has now been fixed. If anyone has already built this then if you can add a 2K resistor somewhere between the germ transistor emitters and ground that should sort it out.  Or you can use then fix layout John did at the bottom of this page.  The main layout has been fixed with an extra column being added to accommodate the resistor

As usual with Bjorn designed stompboxes, a great sounding fuzz.  2N1308s should be available on eBay but if you can't find them, just throw any NPN germaniums in there.

Info about the original:
The Candy Apple Fuzz is one of Bjorns first BJFe circuits (along with the BBOD and DRD) ... it was made to cover the nastier side of vintage fuzzes and it does just that and more … over the years the one recurring request was to make it a bit smoother and more musically manageable ... when it came time for the BearFoot version he did just that by adding a treble control to reign in the rasp as needed… and he also adjusted the circuit to germanium transitors, which are smoother and more musical to most ears ... BUT silicon has its own musicality and many just like the full on unruliness and extra rip of silicon ... now you have a choice as we introduce the original silicon formula CAF ... Silver/Silicon ... Gold/Germanium







And the quick fix for anyone who built using the original layout, the resistor value should be 2K.



50 comments:

  1. Wow... this one just went up on the top of my make list
    Demo sounds awesome

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    1. I have a pair of OC140s that are for a fuzz face from small bear sitting in my pile of transistors... will those work ok you think?

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    2. I think they would be perfect

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  2. i absolutely will build this. Amazing sounding fuzz

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  3. thank you! I love this one -

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  4. son of a bitch...

    *sigh* I'm about to build another fuzz pedal. I got a fat sack of MP38As. I hope those will work.

    Is "compulsion to build 50 different fuzz pedals" a sign of lead poisoning?

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    1. MP38As should be perfect candidate, very low leak and nice gain ranges on those.

      And no. It isn't. I have no clue how many fuzzes i've built by now... :)
      +m

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  5. Hey Heath - you got a DCA55?

    What kind of hfe and leakage are you getting from those MP38A?

    I just scored a bag of 100 Texas Instruments 2N404. Low leakage and perfect hfes for Fuzz Faces, etc, and even a bunch 200+

    Haven't had such good luck with NPN. I keep getting super leaky crap

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    1. I have one. The gains with my MP38As range from around 60 to 120, so no 200 readings, but with really low leakages those are really good for fuzzes.
      +m

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    2. Yes the MP38As are the only consistent NPN germaniums I've had. Good gain range for fuzzes and all 50 had minimal leakage. They're a really good buy if you can get them.

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    3. Incidentally I bought a bag of 100 x 2N404's as well, and they're excellent. PNP of course but all within a good usable range for the fuzz pedals we build with a few higher gain ones thrown in for good measure which is nice, and also with very low leakage.

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    4. I got 25 but only range between 40 and 80 with v low leakage. Have to get some more now.
      If you don't mind disclosing, where did you find the 2N404s? - I've only got them from minifux off ebay, all have been good but range between 80 and 150

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    5. Yes mine came from Minifux too, I paid £14 for 100 :o) one of my best buys ever!
      You've just got to keep your eye on his auctions and sometimes you get lucky.

      Most of mine were between 80 and 150 as well, but a few went up closer to 200.

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    6. Thanks Mark. Wow that was a good purchase. I've been getting them for about £5 for 10 - I seem to miss the good deals, even Russian's are now getting pricey too. I haven't had much luck with European trannies, ACs etc - all seem to be low gain, leaky or not working.

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    7. Yes the Russians are more expensive now than a few years ago, I used to get 100 for about £10, but even with the slightly increased prices, they're still much better value than the NOS Newmarket and the like, and as you say, at least you know they will be consistent and I've not bought a single dud yet. You can pretty much guarantee than anything NOS and sought after will be expensive and shite.

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    8. A little late to the party, but yeah, the MP38as are surprisingly low leakage. I think I might have found one that I was bothered enough with, leakage wise, to put in the "iffy" bag. Of the rest of them, a very small amount were pretty low hfe... but then, those are still useful. Joe Gore gets a crazy sound out of his "Fiend Face" modified fuzz face circuit by swapping one of the germs out with a really low (like REALLY low) hfe germ.

      "One Fuzz Face recipe I like: using a REALLY low hFE transistor for Q2. You can even try installing a germanium transistor “upside down.” (A, transistor of, say, hFE 150 might have enough leakage to measure hFE of 5 or 10.) The results are counter-intuitive: low-gain Q2 can yield an ultra-fat, square-wave-flavored grind."

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    9. Also, I've had super good luck with MP20a PNP Russians. They kind of feel like the PNP equivalent of the MP38a. Again, not super high hfe, but mine were fairly consistent in the 50-100 range and I think 1 out of 30 had a leakage I was unhappy with. They freakin breath fire in a Sola Tonebender.

      Good luck finding a decipherable data sheet on them, though. It's funny.. but Russian starts to make sense after you stare at it for a few hours. Not a lot of sense, but some :p

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    10. AC176s may be ok alternative too. Minifux has them, but only about half of them are usable (they read as diodes on DCA55, have way too high leak or way too low gain). Other half is great with hFEs around 50-150 with moderate leak.

      Russians are the greatest. Consistent and reliable.
      +m

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    11. Mirosol, I've had exactly the same issue (also with pinouts being reversed) but with most of my ACs and GCs. Peter (minifux) says this is a issue with the DCA.
      I now prefer to invest in the Russians and some 2Ns - hopefully I will get some decent ones which sound good (and enough to keep me going with this diy addiction I'm now suffering)

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    12. Kind of fitting, if you think about it... The iron curtain prevented a lot of music that the rest of the world took for granted from getting through in any abundance... and now we rock the fuck out with the help of friendly Russians, Bulgarians, Ukrainians, etc with fistfuls of fuzzy germanium transistors.

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    13. Hmm.. Guess i'll need to check if i have my old measuring rig still somewhere. I do find i quite hard to believe that the fault is within the DCA55. It is straight on calculation of conductance and nothing more. If the tool is at fault, it should manifest itself on other measurements too.
      +m

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    14. I've had a few Russians read as bi-color led's or some other type of diodes on my DCA55. I don't know why, so those are the only ones I'm ever iffy about, cause the leakage always acceptable. I haven't had any with leakage over 250uA. Even those that are way over what they should be (a few in the high 200's-300's, even one that tests over 400!!). I'm still sorting threw everything I bought and going to put up my results in the old post from Javi about germaniums. To give everyone an idea of how much I got, it was 1.625kg (3.58lbs) worth of different transistors including 200 MP38A's. Figured I should be stocking up before the USSR closes their borders to trade.

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  6. I forgot the seller, but mine was an eBay buy too. I paid $85 for my bag, well worth it for what I got.

    Dang Mark, I'm almost upset that you got those so cheap. I thought I found the sweet deal!

    I think I'll grab a bag of the MP38A as well. Hope I get a decent amount of 100+ hfe. I have some American (also TI) NPN germs that are pretty good, plenty high gain, but sometimes too leaky

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    1. Even though you paid more, when you think about it $85 for a bag is still really good value. I'm sure most people would be happy to pay $0.85 for a consistently good germanium transistor in a useful range. I was just lucky and got them for 2N3904 money.

      I've had really good results with the Russian transistors around 60 to 80 hfe, much better than you might expect. Most of my MP38A's were in this range. Looking at my spreadsheet only 12 were above 80.

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    2. Can you combine them like a Darlington (this is an area where I am particularly ignorant)? Would there be any point?

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    3. If you are referring to germanium transistors in general, yes you can make Darlington pairs with them. Just look at the Tone Bender MKIII or any of its derivatives like the Buzzaround. Q1 and Q2 in those form a Darlington pair

      The point is basically just to multiply the gain, but you also end up multiplying leakage and noise, so if either transistor is too leaky or noisy it's no bueno

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    4. Wow.. I never put 2 and 2 together on that. Eureka, indeed!

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  7. Question about the nature control. i tried to make a schematic bsed on the vero. so nature lug 1 is connected with the base of Q3 and lug 3 is connected with base of Q4. lug 2 is tied to the ground, am i right? if you turn the nature fully ccw, the base of Q3 is on ground potential, isn't it? so the signal goes to ground? maybe i missunderstand anythin or read it the wrong way, but then the sognal goes to ground or not? Q3 and Q4 are parallel correct?

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    1. Yes that's exactly right

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    2. but in the videos i saw, there was still a signal when the nature control is turned ccw. i am confused! :/

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    3. Yes because collectors and emitters are in parallel, so even if one base was grounded you'd still get an output. This fuzz has an octave effect and I've seen this kind of arrangement used previously to do that.

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  8. I built this one today and it definitely doesn't work. do you have a schematic (or a link to one?) that I can check the vero against? I had every exact component in stock so I didn't use any substituions

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  9. it works with the 2K resistor fix now.

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    1. Thanks to John for verifying and testing behind the scenes! :o)

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  10. Any hope for the silver or gated versions of the circuit?

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    1. I'll certainly do a layout if they get traced or I get some decent gut shots where I can see the values (or check them with the pedal owner) so it can be compared to this version for differences. But like John said, I doubt they'll be hugely different from this one and so I wouldn't expect to see anyone from FSB get one specifically to reverse. This is the one most people will be interested in after all.

      But yes I'll definitely do the layouts if I get contact from a willing owner :o) In the meantime consider socketing the germaniums (and the emitter and/or collector resistors of those two transistors so you can tweak), and trying it out with a variety of silicons just to see what you think yourself. Everyone should experiment with these circuits to try to tailor them to their own preferences, we all know that's how the next big boutique pedal is born in lots of cases.

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  11. IMO, the gold (non fuzz version) is pretty heavily gated already with the nature knob fully CCW. I'm not certain, but would imagine that the silver version just uses fairly low hfe silicon NPN's instead of the 2N1308's (like maybe some 2N2369's?).

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  12. To someone who has successfully built this circuit, does everything work right for you?

    I'm a bit iffy on the transistors I'm using (AC127k) but the FUZZ sounds decent... nothing to write home about, but not bad.

    My problem is that the only pot that seems to work is Volume.

    Nature seems to work like this.. Center detent, normal fuzz. Turn to the right, shit, shittier, shittier still... Turn to the Left, shit, shittier, possible shittiest. Just not good at all. One direction it's muffled and the other it's just crap, like it's balls are being drained away shrunken. At no point but the center does it sound at all good. Yes, I'm using a 20k W taper pot.

    Fuzz does not change the Fuzz at all, it just makes some not-quite-crackle sound, more like a faint crumple. When turning it, the volume also does a dip... not at a set point, but just from being turned. The quality or quantity of Fuzz does not seem to change.

    Tone for the most part doesn't seem to have any effect except the last 10% or so where it seems to just boost the volume or gain a bit.

    I don't have my camera handy at the moment to take a picture, but I will as soon as I can.. was just wondering if anyone had similar experiences. I noticed the number of "success" posts here was rather miniscule which also made me wonder.

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    1. Your description of the Nature pot sounds about right. Someone said it just has a very small sweet spot when the octave effect becomes more prominent and the rest sounds pants. Fuzz should work though, it's the same as a Big Muff fuzz control where rotating counter clockwise puts the pot's resistance between the input and output of the pot and takes the output closer to ground. The treble control is a simple high pass filter which rolls off low end as you rotate clockwise. Maybe someone who has built it can comment on their results.

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  13. I recently wired this one up and am also a bit weary of the control pots mostly the nat. and fuzz.

    I have found that once you set the nat. pot to where you want it (which will crack a bit) you need to fine tune the output with the fuzz pot. There seems to be a small range of fuzz values that give a nice output for a certain nat. setting. Everywhere else on the fuzz pot causes feedback and noise. I haven't checked the leakage or hFE of my 2N1308's yet so that is my initial suspicion. The treble works well though it may be difficult to hear its full effect if your fuzz is not clear.

    Any one who uses one of these want to comment on the control of the nat. and fuzz controls that would be great.

    Thanks

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  15. Hi, did everyone make it? does it work well? will it work with B20k instead of W20k and with J201 instead of 2n5952?
    thanks for any answer, :)

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  16. I can't find the 2N1308. I don't know which replacement Germanium transistor to choose... Can someone please help me? I'm ordering at musikding (http://www.musikding.de/Germanium-Transistors). Can I only use the AC176 NPN ? What hfe do you suggest?


    I also took 1n914 silicon diodes as replacement for 1N4148 because 1N4148's are not availeble right now. Is that ok?

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  17. AC176 is pretty leaky compared to 2N1308 in my experience. You can get 2N1308 on eBay, or try 2N1306, 2N1304, or 2N1302.

    Or maybe MP38A

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    1. Ok thank you! I'll look for that!

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    2. Used the MP38A's. Pedal seems to work great!
      Is there a way to reduce the treble more?

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  18. When I turn the nature knob ccw the sound starts to sputter or to be gated. Is this normal? It seems like in the youtube videos this does not happen...

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  19. trying to get this fuzz built but no bat42 diodes. what would be a good replacement? thanks!

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  20. Noticed a added cut in the upper right corner next to the 2k resistor but it still says "13 cuts" should i add this cut with the 2k-fix?

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