Tuesday 27 August 2013

BJFE / Bearfoot Pink Purple Fuzz

To keep the collection complete this is the second recently reversed BJFE/Bearfoot pedal, drawn up by mmolteratx, thanks again Matt.  Again this one sounds great to me.

Info about the original:

The Bearfoot FX Pink Purple Fuzz blurs the lines. Is it pink or purple? Is it fuzz, overdrive, or distortion? In terms of the color—can’t it be both? In terms of the tone? It’s all three, depending on how you dial it in. The Pink Purple is very high gain, while remaining very low-noise, housing all your daily fuzztones (no crazy octaves or gated fuzz here) and blurring the lines between fuzz, distortion, and overdrive—with a versatile mid-EQ knob that takes you through a range of useful fuzztones.

Bearfoot FX is the brainchild of Bjorn Juhl of BJF Design and Donner Rusk of Donnerbox. Every pedal is handpainted and no two are exactly alike. The pedals now ship with a plain, unpainted bottom plate to help ensure the most secure contact with adhesive Velcro for use on pedalboards. Bearfoot FX pedals are handmade in St. Louis, Missouri, USA.







70 comments:

  1. I've got ALMOST everything I need to build this.... except the W-taper pot and NPN Ge transistors. Rest assured this one's getting built. Wow.

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  2. What is that mutant based on? looks mighty interesting.

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    1. It isn't based on anything I've seen verbatim, but it's just 3 cascading gain stages like we have seen before, with a Big Muff type fuzz control and a often seen (for BJFE) Nature tone control. The JFET, silicon BJT and germanium stages will make a difference to things we've seen before with common transistors, and knowing Bjorn he's got it bang on.

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  3. When you're sat at home bored with nothing to build, do you stick pins under your finger nails?

    :o)

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  4. No, I prefer AC128s, my fingernails look cool after! But I have to order some 5952 before building this one :P

    BR!

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  5. I found it to be a little dark so I swapped the 470p for a 100p in mine.

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  6. Is the W taper pot necessary? Looks like the other "nature" controls have used linear taper.

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  7. no no no
    not another one~! on the list... This one should be fun... sounds FAT


    Man, wish that Wampler Velvet Fuzz would hurry up too! hehehe

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  8. This is one of the coolest blogs I have ever seen. I've built a couple of your layouts. Never a problem. On this layout - which is Q1,2,3? Also I notice you never include the schematic. Just wondering why.

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    1. You're welcome dsx!

      Q1 is a JFET, so its pinout is DSG. Q2 is a BJT (bipolar junction transistor) and Q3 is a germanium. We tend to use those transistor images for each type. Nowadays, we don't usually depict germanium transistors with BJT transistor image/symbol, so the pinout is shown as black dots. So in essence, the transistors are 1, 2 and 3 from left to right.

      The schematic question is one of the questions that pop up quite frequently.
      Schematics are not published by us because we do not have any rights over them. We would need to ask permission for each schematic from the author. All that in being that we're not in the business of breaking any intellectual property / copyright laws. Plus, all the schematics come from the web - so if we can find them, you should be able to find them too.
      +m

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    2. Heyas dsx
      The freestompboxes site is usually where I poke around if I ever need a schematic... But I am having to give a huge THANKS to IvIark @ mirosol for these fantastic layouts, since they are imho the best to be found for vero - nice and small

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  9. I have no sound out of this one, but I had to use replacement transistors for Q1 & Q3 :
    Tried MPF102, 2N5458 & BF245B for the J-FET and AC176 for the NPN Ge

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    1. Did you get the pinout correct for the JFET? The 2N5952, for whatever reason, has the opposite pinout to most JFETs.

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    2. I was just going to post that too. Check all the transistor voltages, that should give the best clue.

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    3. I checked the pinouts with my DCA55
      Here are my voltages :
      Q1 (2N5458)
      D 4.14
      S 3.42
      G 3.46

      Q2 (BC550C)
      E 0
      B -0.05
      C 7.65

      Q3 (AC176)
      E 0.77
      B 0.86
      C2.29

      Battery reading 8.73V

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  10. This pedal made me buy 14.7K resistors. I said I'd never do it, but I did.

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  11. Not related to this pedal in particular, but...

    How does everybody do their graphics / text? I see a lot of great looking pedals and that's where mine are lacking! Thanks for any input!

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    1. Try starting with something simple - think about an object that goes along with the theme of the pedal, search google images for a line drawing or outline of that object, mess with that image in GIMP (free image editing software) a bit, and that gives you a graphic.

      Cool fonts can be had for free from dafont.com and similar sites.

      Lay it all out in GIMP, print it out on a waterslide decal, and bob's your uncle.

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  12. Has this layout been verified? Johns post above seems to suggest that it has.

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    1. This comment has been removed by the author.

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    2. Mine isn't working as mentionned above, but I can't say if the layout isn't correct, might be my build.
      I'll have to probe it

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  13. I drew my own vero a day before Mark posted his (and mine's a little larger), but i'm sure that Mark's is correct.

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  14. I have been know to have the occasional DOH moment, but I've looked it over and nothing obvious is standing out to me.

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  15. Geesh, this place is addictive!

    So, I am putting an order together and the transistors are hard to come by.

    Mouser shows BC550C as obsolete. Then it has available BC550CBU,BC550CG,BC550CTA. I'm thinking the BC550CBU is fine? Tayda has BC550B, but the Hfe is a little lower for the B than for the C, according to the data sheet. I hate to order a few transistors from mouser. The shipping will kill me!

    2N5952 is out of stock at Tayda, smallbear has it, and mouser requires a purchase of 1300 transistors!

    2N1308 is a complete mystery. No one has it, except Ebay who sells them for minimum $12.00 after shipping. Seriously? Any ideas on what the best course of action is? Reading through the germanium pairs at small bear, I can't figure out what a lot of them are. But again, I don't really need a matched pair. Help!

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  16. 2N1306 is available at small bear, as well as a "work-alike" 2N1306. Woul dthat be a good replacement for the 2N1309? What sort of Hfe should I be trying to get in that Q3 ?

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    1. I mean, would that be a good replacement for the 2N1308?

      I think I found my answer. The spec sheet just shows a slightly lower minimum Hfe for 2N1306 than 2N1308. But hey, these are germanium, so I doubt the "minimum" will come into play anyway. Especially if I order from Smallbearelec.

      Now I have 3 projects on deck. Dang this website!

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    2. Any NPN germanium transistor should do the trick. I bought some Russian MP38A's from eBay which are great for things like this.

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  17. Mark, what do you think of my voltages posted above ?

    (and BTW, what does DOH stand for ?)
    Thanks

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    1. Q2 looks very wrong to me, and even Q1 looks slightly dodgy. I've asked krzabe below to post his transistor voltages from his verified build so we have a point of comparison.

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    2. Ah ah, I've never watched an episode, can you believe that ?

      Thanks Mark

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  18. Verified!

    I thought the Nature pot was wired backwards but I realized it's supposed to be that way (ccw being brightest).

    Didn't have any 14k7 resistors. I had some 5% 15K carbon film so I looked for the ones closest to 14k7 which turned out to be around 14k82s.

    Fortunately, I had one last 2N5952 and plenty of BC550C. I didn't have any 2N1308 but used AC127 which worked super well on this circuit.

    It sounds like the demo. I'll post some pictures of the gut shot soon. Now I just need to find some nice box for this :)

    Awesome layout as usual! Thanks lvlark!!

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    1. Oh I used b25k pot for Nature. It worked just fine.

      Here is a picture of my board:

      http://i1305.photobucket.com/albums/s547/abepay/pp_zps44bd6d6f.jpg

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    2. Awesome, thanks for verifying and for the pic. Could you post your transistor voltages if you get a chance. Thanks!

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    3. Nice, now I know my build is faulty :-)
      Yes, voltages would be cool, thanks

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    4. I'm not good at measuring things but I tried..

      Q1 (2N5952)
      D: 5.57
      S: 2.50
      G: 0.00

      Q2 (BC550C)
      C: 5.42
      B: 3.01
      E: 2.68

      Q3 (AC127)
      C: 2.48
      B: 0.91
      E: 0.83

      I hope this helps!

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    5. Kr, I think that your build lacks a 22uf cap between !1 source and nature 1. Check it

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    6. Good sighting, thanks Javi!

      Funny how it works fine without it. I guess I should throw that in and hear the difference. Good thing I didn't box it yet. I hate unboxing pedals to repair/tweak stuff.

      krzabe = crazy abe :)

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  19. Received today the 2N5952, so I had to build it. I can confirm that it sounds (great!) and as it's supposed to. I can't find any problem, so you'll have to triple check your build, Altrax. My voltages are very similar to krzabe one's, so it seems that you have a problem in Q2 area:

    Voltages:

    Q1 D 5.38 S 1,79 G 0

    Q2 C 4.88 B 2.85 E 2.29

    Q3 C 2.73 B 0.75 E 0.64

    Battery reading: 8,85v

    Like the sound, but it's to late now to play high volumes, so tomorrow will check it in deep.

    BR

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  20. Finished and sounds great. Few subs. 15k carbons measuring around 14k76 to 14k8 20k Lin for Nature. AC176 for Q3

    Only issue...with Fuzz at full, there is a small spot at about 80% sweep on Nature pot where a lot of oscillation creeps in. Pitch of oscillation rises till about 90% of sweep then pot works as expected. Maybe a bad pot? Too much gain?

    Not really bothered as I've already found my set and forget settings but thought it was worth mentioning.

    Cheers for the fantastic layouts!

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    1. hmm. not sure why you'd have oscillation at any setting since mine doesn't have it at all.

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    2. Yeah it seems strange. Ill swap the pot tomorrow and see if it makes a difference. Maybe not but its a quick test so here's hoping.

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    3. Just finished this one. Fantastic pedal! Used NTE312 (alt for 2N5952) and russian MA37 (sub for 2N1308). Compared closely to the Proguitarshop demo and sounds to my ears exactly the same (or extremely close).

      If anyone else is getting oscilliation at some spots on the fuzz and/nature pot sweeps, it might be you have the germanium tranny (2N1308, in my case MA37) reversed - as in collector and emitter need to be switched around. I found that even when reversed, the pedal will appear to "work". In fact, the gain is ridiculously high when fuzz is maxed if the germanium tranny is reversed, and one might think that pedal is working as intended. Other pot positions sound pretty good too. But you will get oscillation at some spots and the same knob positions as the demo won't produce the same sound (you'll get more gain than you should).

      Great job on this layout Mark! Thanks!

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  21. Hey guys, I'm just wondering is this the right 20k w pot for this project?
    http://www.taydaelectronics.com/20k-ohm-w-taper-w20k-tone-control-potentiometer.html

    Cheers!

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    1. yes, that one will work fine. I used one of these since I prefer alphas with solder lugs and a solid shaft.:

      http://www.pedalpartsplus.com/mm5/merchant.mvc?Screen=PROD&Store_Code=PPP&Product_Code=7520&Category_Code=16mmW

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    2. Thanks for your help John! ;)

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  22. Finally, I was in the mood to box it, and here it is:

    https://scontent-b-mad.xx.fbcdn.net/hphotos-prn2/1385611_556834091055110_1376833249_n.jpg

    BR

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  23. Wow, this is a killer fuzztortion. Enough gain with a tight bottom end and fast attack to act as a standalone dirt pedal for high gain stuff into a clean amp.

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  24. God I regret selling my clone already. I gotta build another one.

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  25. Anyone got a good link for 14.7k resistors in the UK? Planning on building this with an 2N5458, BC550C, AC176.

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    1. Just use 15K. Bjorn only uses 14k7's because he bought a huge batch of them a few years ago in a closing shop sale, if he didn't have them I'm sure he'd be using 15K too.

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  26. Hmm, quite weird. My first build had exactly that ridiculous amount of gain on tap and I used it maxed out - it sounded amazing. Now I made another one which sounds exactly the same but I get crazy ass low frequency oscillation at certain points of the nature pot taper. I'm 95% sure the tranny is the right way around, I tried a few different NPN germaniums even. If I put it the other way around it certainly helps and I only get oscillation at one point of the taper which is something like 15% from the beginning. Less gain and actually, doesn't sound as good. Not as juicy, open and midrangey. Annoying.

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  27. I built this yesterday and it sounds really good but I'm getting the same oscillation problem as myrkky and ayeritehi

    It's annoying because it sounds super good except for the oscillation. My voltages line right up with myrkky and javi's working builds if you account for my power supply putting out about 9.6v

    I'm going to keep looking for a fix

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  28. Built this some days ago and i love it! It`s a realy great fantastic high gain distortion pedal and i have no oscillation anyway. To get closest to the 14K7 resitors i used 15K and 1M in parallel (looks funny too). But to make it perfect for me i`m thinking to get some more bass through the circuit. Any sugestions what cap to increase? Thanks for the great stuff!

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  29. Jut build the pink purple fuzz but unfortunately it isn't working. The only sound that is coming through is hiss. The hiss can be altered with the nature and the volume control. When the nature pot is adjusted you can hear more bass in the hiss. That way I think the nature and the volume pot are working like they should.

    Measured the transistor values and they seem to be almost the same as JaviCAP.

    Q1 (2N5952)
    D: 6.28
    S: 1.80
    G: 0.00

    Q2 (BC550C)
    C: 5.48
    B: 3.19
    E: 2.61

    Q3 (AC127)
    C: 2.30
    B: 0.94
    E: 0.86

    Did check the orientation of all components, found that the 10K resistor was not placed correctly, the rest seems to be OK.

    Can someone help me out?

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  30. I built this pedal and I really like it. The 2n1308 is very hard to find. I used the 1n4001 diodes instead of the 1n4007's as they were recommended. I used the 20W for the nature which was a pain to order. Over all I really like this pedal and it is a very straight forward build. Here is a picture of my working build if it might help anyone. Thank you for the layout you guys rock!!!

    http://s1383.photobucket.com/user/denfox1/media/Mobile%20Uploads/20150622_154142_zpsaeh15pbr.jpg.html?filters[user]=142444066&filters[recent]=1&sort=1&o=0

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  31. anyone find a fix for the oscillation issue.
    I'm getting oscillation with the 2n1308 flipped both way, one way more than the other.

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    Replies
    1. Same issue here. Could it be something with the transistor(s)

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    2. He he!
      I rotated the middle transistor and bye bye oscilation!

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  32. OMG! I loaded up the 'Tonestack w/LPB1' onto this and created a monster. The 'Nature' can be set anywhere and then turn the 'Tone' knob added with the Tonestack w/LPB1 board and.......well you just gotta try it. It's treble Nirvana.

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  33. Couple of mods I did:

    1. Used 2 pots for the nature so now I have independent bass and treble. I did the same on my HoneyBee build.

    2. After some testing I settled with using red LEDs instead of the 1n400x's for the clipping. I find I'm able to dial in the gain I like easier and there seems to be more dynamic range and clarity. Maybe I actually just wanted a distortion after all...

    In regard to the clipping, so far I think I've preferred higher clipping threshold setups (either 1 LED per direction or 2 si per direction) rather than just 1 si per direction. But there's something I can't quite get my head around, and haven't been able to test properly. If anyone has any experience/insight, please chime in. If, in a given circuit, you use 1 si per direction, set the gain knob relatively low and the volume high, then use LED's, set the gain knob higher, and the volume lower, so that both situations have the same level of clipping and total volume... would there really be a difference in clipping character and picking dynamics?

    All that to say, in this circuit you cannot perform that test exactly. I noticed when no diodes are present, as you turn the gain knob up, you get some clipping from the transistors (though the LEDs clip it further). So, using LEDs rather than si will allow for you to turn the gain knob up higher for your targeted clipping level, thus you have 2 stages of clipping (transistor and LED). In theory this would make for a more interesting sound.

    Speculation aside, to my ears the si diodes sounded more compressed and fuzzy, while with the LEDs I could dial in more dynamics in clarity.

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  34. I built one of these too, with separate Bass (C10K) & Treble (A25K) controls. I made two more mods: I bumped the Treble cut cap from 22nF to 33nF and added a C10K pot in series with the diodes. With the Diode pot fully clockwise, it has maximum compression and predominantly odd-order harmonics. As I back off on the Diode pot, the dynamics increase and the even-order harmonics from the transistors come to the fore. This and the Skreddy Screw Driver are my favorite Dirt Pedals.

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    Replies
    1. Poster from March 2018 here. Great ideas! I'm about to open mine back up since the bass knob sweep isn't very good, maybe I'll try your values.

      Btw I'm phi1 from the pedalpcb forum haha.

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  35. I had got the oscillation problem as Ciaran said above−there is a small spot at about 80% sweep on Nature pot where a lot of oscillation creeps in.

    I finally got to know what it was causing.

    A contact resistance of the pot used for the nature control cause the oscilation problem.

    Every pot slider has a contact resistance more or less, and this makes feedback voltage.

    To solve the problem, we have two solutions:

    - To use a dual pot for Nature Control and assign one of a pair to FET side, the other one to Output stage side.
    - To separate Nature Control into Bass and Treble - as you know this is another 4 knob version.


    I hope this will help!

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  36. Hi!

    How do you guys actually do the separate treble and bass knobs mod? I mean I found another totally different layout for that but I want to mod this one to 4-knob version...

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