Monday 14 April 2014

EHX Satisfaction Fuzz

Note that the C7 and the D2-D3 are not present on the original pedal. There are holes ready for those components. Adding C7 as 4n7-100nF cap will increase bass response and adding diode clipping to the place of D2 & D3... Well. That will make this an different animal.



58 comments:

  1. Yay, thanks you guys! Totally building this when I get a free chance.

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  2. Does that mean that C7 and the diodes are optional?

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    1. Yes. The original unit has only empty pads for those with printed diode markings and a "+bass" note. I just placed those for the the layout as adding them is not a bad idea.
      +m

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  3. It's based Os Mutantes Fuzz? : http://fuzzface.es/mods/os_mutantes_fuzz_sch.jpg
    or Jordan Boss-Tone? : http://fuzzface.es/mods/Jordan_Boss-Tone.jpg

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    1. It is pretty much 1:1 with a bosstone...
      +m

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  4. Replies
    1. Yup. 2N2222A with 2N2907 would the transistors i'd use for the circuit.
      +m

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    2. I think KSP2222A is basically the same transistor as 2N2222A, only from different manufacturer.
      +m

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    3. 22222=5 and 2222=4 +A
      is 22222A a typo or is there a transistor with that name?

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    4. So, Mirosol, are you saying 2N2907 if you can't fin 2N3906?

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  5. Hi first post but have been following this site a some time. Great site. You all have helped many many people find their sound. Thanks
    This circuit sounds good. Probably won't be every ones favorite but I like it. I don't think the diode clipping is needed but the added bass cap is very nice. I think the 22n was the best option.
    Thanks again.

    Since this is my first post I don't want to say verified but I believe it is. : )

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    1. I'll tag the post! Cheers and welcome!
      +m

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    2. Would it be possible to use a variable resistor or a tone pot on C7? That way you could dial in the perfect bass tone.

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    3. I meant variable capacitor.

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    4. I should have said, variable capacitor.

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  6. This is indeed a Jordan Bosstone clone.
    It is a great circuit for a starve pot (I used a 250k !!!) on the 9V voltage power supply.
    This circuit goes into lower octave when starved.
    It is really wicked. Highly recommended mod.

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  7. Very nice! Do you just omit C7 and D2-3, or does it have to be jumped? I'm guessing no... but like to make sure before I start building this one.

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  8. Ok. I built it without the C7 cap and the extra diodes. Not bad, just a kind of slight fuzz/overdrive. Sounds good. Then....I added the cap and the diodes. Holy zombie jeebus. What a difference. So fuzzy yet, it sounds like an old JTM45 past the breakup point with some fuzz to boot. Such a badass pedal. This goes well with the Woodrow that I built (courtesy of your excellent layout). Fantastic job Mirosol! I recently found (yes found) an old Oliver G150R in the trash outside of a church in February. I've been slowly restoring it. Right now, this thing sounds amazing in front of it.

    Thanks a bunch!

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  9. Does anyone have the schematic for this? My build sounds like poop. I went over it several times to check for problems, but it's built right... just sounds very farty and dull. Doesn't really "fuzz" unless I strum really hard... then *fart* Maybe I should dunk the transistors in Pepto Bismol? :D (I used a 2N2222A and 2N3906 as noted, and double checked orientation, too) Thanks!

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    1. OK saw the link above to the Jordan
      bosstone.
      i'll breadboard this one and tweak till it works and post what i find in case someone else has the same problem

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    2. OK - breadboarded from the schematic and it worked like a charm, using mylar caps... so I pulled the ceramic caps in the build (Why did he use them, why!?) and now it's a GREAT sounding fuzz! Thanks mirosol for the great layout! Only thing I noticed is that although the tranny 2N3906 is labeled correctly in the pins, the symbol is reversed. Probably doesnt matter!

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  10. Hi guys... I really wish to say that mine is working too... but doesn't! it is not my first build, but I really can't figure out where's the problem! Maybe because I used Mylar caps?

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  11. By the way, I used a 2N2222 for Q1 (TO-18 metallic package), and 2N3906 for Q2.
    On Q1, I measure the following voltages:
    Collector: 4V
    Base: 0.5V
    Emitter 0V

    On Q2 the followings:
    Emitter: 4,7V
    Base: 4V
    Collector: 0V

    With an audio probe I found that the signal goes thru Q1 well, but when reach Q2 it makes a mess! As I touch the "E" on Q2 I hear a huge and continuos beeep (... I hope you understand eheh...)....

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  12. Ok, so, after testing I figured out that Q2 is the problem: if I remove Q2 and I put the probe on its "B" pad, than I have no more noise, and a really huge fuzz...
    But anyway it is not working "as it should"...
    What's the problem with PNP transistors?? (I tried also BC557 but it's the same...)...

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  13. I should know that Miro knows what he's talking about. I built it straight first. Quirky, gritty sound, not terrible but not particularly useful. Added the mods and it's a completely different animal. I might tone down the 22n because I am getting too much bass with the P90's. Will try it with Humbuckers tonight, but it will be okay to lower that cap a little. Thanks

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  14. I'm really liking the sound with the starve pot. The octave down sounds awesome I'm trying to figure out how to get it to sustain longer on the octave down notes. It is hard to get the notes to drop sometimes too I used a 1m for the starve pot which is not what I wanted to use but I had extra. It seems like the sweet spot is kinda small and I have to pick very light sometimes for the octave to work. Something about octave down sounds so good to me. I just finished a mxr blue box and I'm getting ready to make the shocktave

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  15. I like it with 82n and germanium diodes.

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  16. Is this layout missing C6 (100uF)?? https://www.google.com/search?q=satisfaction+Fuzz+schematic&source=lnms&tbm=isch&sa=X&ei=9DZyVcXrM6XcmAX78oKYDw&ved=0CAgQ_AUoAg&biw=1440&bih=763#imgrc=kArM2nBeZaxIIM%253A%3By-lliTdh1GNMYM%3Bhttp%253A%252F%252Fmirosol.kapsi.fi%252Fwp-content%252Fuploads%252F2014%252F04%252FEHX-Satisfaction.jpg%3Bhttp%253A%252F%252Fmirosol.kapsi.fi%252Ftag%252Ffuzz%252Fpage%252F2%252F%3B1280%3B550

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    1. short answer is yes, long answer is no. it's just for power filtering, and D1 is for polarity protection. C6 was just removed as it doesn't seem nessacary for this build. if you want to add it just add 1 column to your board and add it from 9V to ground.

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  17. I build it with the 22n and tried it without diodes. Nice sound, but with a strat I might find useful some more bass. Should I try a bigger cap instead of 22n, or adding the diodes (which I will do later btw, probably with a switch) increase the bass response?
    I apologize for my ignorance...

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    1. Try a 100n input cap. If that's too bassy, knock it down to 68n or 47n. Clipping diodes won't affect the bass response.

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    2. Thanks for the quick answer Joedoc, if I have some time today I`ll try the mod and post the result.

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  18. Hello.
    Will 100k linear pots make any difference?

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    1. the taper of a pot doesn't really make a difference in what it does, just how you hear it. for instance if you have an overdrive that it seems like all the gain is bunched up at the top (CW), if you change it to a different taper you'll change how the gain changes as you alter the pot.

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  19. Hi! I'm a beginner in building pedals. I have few questions about this build.

    1. Does changing the input cap 22nF to .1uF and placing a .1uF in C7 would produce octave sounds just like the mod on the Nashville Bosstone?

    2. How can I create a sweepable knob from the stock sound - mid - bass? Like the JHS mod but not switchable.

    3/ How can I increase the sustain?

    Thank you so much!

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  20. My regular Bosstone clone is a fuzz with trebel boosting effect.
    The EHX Satisfaction is similar to the Bosstone with 8,2nF in C7.

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  21. Really good fuzz! Didn't have a 2n3906, so I've used a BC557 and added C7 as suggested. I get a cool octave effect when I rollback the tone. Only problem is a started getting a whinning noise after I added the clipping diodes (will investigate that later). Btw, you can make it more 1590a-friendly by ommiting the Attack pot (it's just the input volume) by connecting the attack 1 & 2 wires and using your guitar volume to control it instead.

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    1. I am getting the same thing when adding the clipping diodes. Tried 1N4148s and some 1N394s. Same whinning thing in both cases. Note that i made mine switchable able between standard and added 'C7 and diodes'.

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  22. Hi Rickst, I made this quote a while ago but In regards to omitting the attack pot. Whilst its a bit weedy at around 9 o clock i have found its actually very interactive with the output if set from 10 o clock onwards. Especially when you open your amp up.

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  23. Hi guys, I'm totally new to DIY and this is going to be one of my first tries. I would like to know if the extra cap and diodes can be made switchable, so I can have both the stock and modded version at a flip of a couple of switches, or do I need to build 2 version sof the pedal if I want to have both sounds. Thankls In advance.

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  24. hi all, Imade this, its very very quiet, amp is almost on full and still very quiet, the sound coming out is slightly breaking up definately not fuzz. i had to change some of the resistor values, the 18ks are 20k and the 560 is 510m could this affect it?

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    1. also had to use a 4148 diode as polarity protection as well as clipping.

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  25. Did you use NPN for Q1 and PNP for Q2?

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    1. i used the exact P/N for q1 and q2

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    2. 2N222A and 2N3906, i think something has happened though as i took the 2N3906 of the vero and replaced it with 3 wires, connected them to a solderless development board and then tried other P/Ns, didnt make a difference so i disconnected it completely just left the 3 wires exposed and it was doing the same, like it was not using that part of the circuit.

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  26. What are your voltages on the transistors?

    I think the best way we can help you is if you post photos of the front and back sides of your board in the debugging section of the forum. Voltages will help as well

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    1. ok so i looked at the schematic of this circuit, the transistor pairing looks like a darlington pair(more accurately a compound pair). i decided to swap to a true darlington config and use 2x2N2222A transistors, had the same issue

      On Q1, I measure the following voltages:
      Collector: fluctated around 4V
      Base: between 0.5V and 1.2v
      Emitter 0V

      On Q2 the followings:
      Emitter: ~4V
      Base: ~4V
      Collector: 0V

      all fluctuating erraticaly.

      the sound is there now, its fuzzy, but takes out any sustained notes, higher notes and single notes cut out, if i play lightly its farty and crackly. some research online indicates i may have a transistor biasing issue now?

      thanks

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  27. It's actually not a darlington configuration even with both transistors as NPN. Look how Q2 has the collector grounded. It is set up for a PNP transistor in that position. There are other big differences from a darlington configuration, but anyway..

    One thing that seems odd is that you say Q1 collector is fluctuating but no mention of Q2 base fluctuating. Since these are directly connected I would expect the voltage to behave identically.

    Anyway, since this is a verified layout there is an error somewhere in your build. I don't think I can help you any further without seeing the front and back sides of your build. Link to some photos here or post photos in the debugging section of the forum for further help

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  28. your right, my mistake(still learning) loving the info though. i gonna start again, try and get a bit neater, i cant see any bridges but may have some. if that doesnt work il post some photos.

    cheers

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  29. Does anyone know how to include the knob on the side that JHS added to their now-discontinued mod? A friend just bought one of these hoping to have JHS mod it, only to find they're no longer doing it. Thanks!

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  30. Can anyone help - I've built this and have cuts and links in the right places etc.

    I've audio probed and get nothing past Q1. I have sound on the base of the transistor, but nothing through the other pins. This is pretty confusing, especially when I've changed the transistor out just in case it was faulty. I've used a 2n2222a transistor

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  31. I think two cap values in the above layout are wrong. The build above is too dark when compared with the EHX pedal. The 4.7nf cap above (c4) should be replaced with the 1.5nf and the 1.5nf above (c3) should be replaced with a 47pf (per the bosstone schematic). After these changes, my build sounds exactly like my EHX.

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    1. How did you determine the correct value of C4 to be 1.5nf? I agree that this sounds a little too dark. I didn't find changing C3 to do much if anything.

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  32. im an absolute newb. when i look at vero layouts, i see the components and the track side the same. yet obviously when u flip the board over, to put the components in its reversed. so which one do i follow? the trackside or component side? i mean am i over thinking this or just an idiot? I cant get anything to work ever.... so I am asking the stupid questions..

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