Tuesday 15 July 2014

OKKO Dominator

Modded slightly to include a Mid Range pot instead of the switch in the original to give you complete variable control of the mids frequency rather than just 3 preset values.

I've done the charge pump on a separate board in an attempt to keep it 1590B friendly by allowing you to tuck the charge pump board out of the way somewhere, but with 6 pots I don't think too many people will want to do this anyway, so maybe some would prefer to simply add 5 rows to the bottom of the main board to keep it all integrated.  It will fit into a 125B with those extra rows.

As with other layouts I have included a couple of axial caps simply because I have them in that size, but there's no problem using radial in there if that's what you've got.

Info about the original:
Aggressive british crunch, classic heavy metal, brutal modern high gain or anything in between – the Dominator easily does the job.

This box has nothing in common with those overcompressed, artificial sounding "bedroom metal" distortion pedals that disappear in the mix if you try to use them in a real band situation.
Raw natural gain structure, explosive attack, tight low end and great chord definition make the difference – the Dominator works equally well at home practice or stage level.

The active 3-band EQ with switchable mid range frequency provides effective and intuitive control over a broad range of sounds. (For extensive descriptions of the controls please refer to the user manual).

Just like the other OKKO drive pedals, the Dominator features an internal voltage doubler. The three gain stages and the EQ stage operate on different individually filtered voltages up to 18 volts for optimal dynamic response and very low noise performance.

The Dominator works best in front of a clean amp with some headroom, especially if you use very bass heavy "chugga chugga" settings.







97 comments:

  1. Ha ha, I was thinking of you. Happy birthday :o)

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  2. oh man, i didn't know it's Javi's birthday. happy birthday man!!!

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  3. I didn't know either :P it's on next month, but thank you anyway :P

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  4. It's an early present to keep him busy :o)

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  5. I've cut the vero, but today I'm really tired, The younger kid has been hard to support today afternoon /early evening, so I think tomorrow will start. Luckily, Johnk woud have built and verfied it before :P

    J.

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  6. Not now .. Not!!!!
    It is very tempting

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  7. Lawrd have mercy!
    NOOOOOOOOOOOOOOO My wife will kill me!
    but I don't care HAHAHAHA

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  8. well, i got an early birthday gift from mark too and one right after to keep me busy. mark posted the Diefet - Diezel VH4S Simulator the day before and right after the MXR Phase 90 - 4 / 8 Stage and GoosoniqueWorx Seventheaven. talk about birthday gifts and i with all the postings i still haven't been able to catch up. :P

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  9. Of all the high gain pedals that I've built (including Openhaus and Triple Wreck), the Dominator is my favourite, mine is built from Sabro's layout, including the Mid range mod, too: https://www.flickr.com/photos/118474006@N06/14532411932/

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  10. Happy b'day javi. I'd send you a miniature box but don't got your address.
    jeff

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    1. It wasn't really his birthday I was just joking about it being a present for him after his first post. You'll all have to come back next month to wish him happy birthday. :o)

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  11. Hi Mark.
    REF: daughter boards.
    If you get 18v to the main board does it matter how?
    jeff.
    p.s. I have not thanked you in a while. I am a guitarist that uses your ~~creations.
    I THANK YOU!!
    Jeff

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    1. Any 18V supply will be ok, but you'll still need a small daughterboard with the regulator on to provide the 15V for the other supply connection. That daughterboard would essentially be the 6 left hand columns on the daughterboard shown above including the two caps and 51R resistor.

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  12. Well,

    Tag this f*cking board :P Sounds extremely great :).

    The only thing is that the Bass knob is not very useful, as happens with many of these high gain effects
    Howewer this is the kind of effect that I really HATE to build. Too many components, TOOOOOOOOOOO many pots, higlhly populated boards. Had no BF245, so used BF244, very similar but (shit!) different pinout

    As usual, fired on first try once corrected the trannies pinout, my problems are only with under 15 components effects :P

    Nice job one again, mate!

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    1. Awesome, nice job matey, thanks for verifying. How do you reckon it is compared to the Openhaus?

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    2. I have now the OPAS, but still not the damned 1n2 poly caps, so still have not finished with all the correct bits the Openhaus, and the Dominator is not still boxed, cannot still make a full comparation of the three beasts (Triple Wreck, Openhaus and Dominator).

      Anyway, for what I could hear from the Openhaus with the ceramic caps and the Dominator, is really interesting. The Openahus is very tweakable and can get many more tones than the Dominator or the Triple Wreck, but the pure sound of the Okko and the Wampler is maybe better to my ears. The Dominator tone is great, and the Triple Wreck too, besides its "fuzz like" booster that I love.

      Cannot choose one of them, all are great and sound killer. You can't get wrong with any of these effects.

      J.

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    3. having built all 3, I would say that the only thing I like more on the Openhaus is the "lower" gain settings, but that's not what I have in mind when I take a high gain pedal... I must say that building it was a major PITA (sabro's layout) and maybe, it has something to do with my appreciation...

      I think the Triple Wreck is the "cleanest", with impressive bass control, I like it a lot for studio duties (often reamp basses and guitars through it), but I don't like the top end that much with my gear.

      The Dominator is overall the most satisfying with the mid range control to me. My main guitar for this is a Baritone Telecaster with Duncan Distortion bridge pickup. My Amp is a Sovtek MIG50 with an Engl cab.

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    4. Anybody had problems with oscillation (squealing) at the higher gain settings?

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  13. nice!!!
    but as says here...
    http://www.daselec.com.ar/N/reemplazo_NE5532__sustituto_equivalente.htm
    i can use tl072 in all the IC's, rigth

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    1. Yes, you can use TL072, or any dual opamp in all positions. But in this effect, the gain is generated on IC1, in the very first opamp stage, and after this is heavily modified, so it's a wise decision to use a OPA2604, a very low noise IC (very expensive too :P)

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    2. thank Javi, and damn!!!

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  14. Hi, sorry for my english ;-)
    I finish this built, and everything works perfectly except the gain stage !
    When the gain is full, it sounds like a small Od, I've try to change Ic1 many times but nothing change.
    Anyone can help me ?

    Thank you

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  15. Hey guys,

    does anyone have any oscillation or squealing with this? I built some other distortion curcuits before (proco rat II for example) an i had many trouble with the oscillation issue. So it would be fine if anybody could warn me before I try this one...

    Thanks a lot!

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  16. the 220u elko on the charge pump board. does it need to be a 25V model? or is 16V ok?

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    1. That's filtering the incoming 9V only, so 16V will work fine for that. All the 10µ caps need to be 25V.
      +m

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  17. Allrighty then... I was suspecting that it could be 16V when i tried to follow them schematics on FSB. Thanks for the confirmation.

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  18. This pedal is so excellent that i could just cry!
    Managed to build some sort of bass fuzz on the first go :(
    Then after replacing them components here and there, i finally noticed that the BF245A's were toasted. So i used J201 instead. Don't know how those affect to the overall character of the pedal (compared to BF245A), since i have no point of reference, but anyhow it is now friggin' awesome. And soundwise it's very versatile too.
    Layout much appreciated :)

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    1. Without squealing??? I think about the okko diablo too, but some guys here had problems with oscillation...

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    2. The only squealing i have noticed comes out very silent when the gain is on max. Some high freq. noise. Not disturbing though.

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    4. Built it, works fine, sounds great. Good layouts, fantastic site! But when the gain is on max, then i can`t go with level to max because near max it begins to squeal realy loud. But only i would say on the last 10% of the level pot cw. So i`m thinking about to change the pot for level so that it would be impossible to get this squealing at any point with volume by full gain. Is there a possibility to change the pot, i mean bigger oder smaller e.g. 50K or wouldn´t it work? Or perhaps any other ideas? Thanks for answers.

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    5. No, just run it through test box. Do you think boxing could solve the problem? Maybe in case of shorter wires?

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    6. Grounded box around the circuit acts as a Faraday cage which usually clears a lot of interference and oscillation issues.
      +m

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    7. Grounded box means what? A normal aluminium box with some rubber feet (like this: http://www.musikding.de/Puffer-selbstklebend-schwarz-14x36) isn`t grounded? Thx

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  19. Always thank you for wonderful layouts.
    I sometimes get a wrong ordering of parts, can you have show the BOM or .diy file?

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  20. I'd love to build this but I'm a complete noob. Can someone please tell me what type of components the symbols stand for? Thanks

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  21. Is the 7660s critical for the voltage-doubler. I can't get a hand of it. I got some 7660cpa. Only different I can see is that the 7660cpa doesn't got the boost-pin on pin 1, for higher switching frequency. Is this critical? I really tries to do the searching before posting but can't find the answer. Will increase the capcitor solve the problem with lower switching-frequency?

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    1. you never want to use a 7660 without the "s," you'll get whining. you can use a max1044 in place without any issues. you can get max1044 easily from tayda.

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  22. Would a 555timer voltage-doubler circuit do the job as good?

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    1. yeap i guess. be sure though to measure the voltage on your 18v. cause most times it's a bit less round ~17v. and that could be a problem because the 78L15 needs at least 18v in its input. all regs need in their input 3v more than the output they suppose to deliver. i've build the clone theory with a 555 daughterboard and it works just fine

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  23. I'm a complete noob to this and was wondering if anyone can help me out with a list of components that the schematics represent.

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    1. Components.
      Resistors (light blue)
      14 10k
      5 1M
      3 1k
      1 22k
      1 100k
      2 7.5k
      3 470k
      1 470r
      1 330r
      2 2.2k
      1 15k
      2 47k
      Capacitors (red and yellow)
      4 220nf
      4 22nf
      2 10nf
      1 51nf
      1 470nf
      1 680nf
      1 68nf
      1 1nf
      1 470pf
      1 100pf
      1 2,2nf
      Electrolytic capacitor(purple and grey)
      1 2,2uf
      1 10uf
      2 22uf
      Ic's and jfets
      1 opa2604
      2 tl072
      2 bf245a
      And for the powerboard
      1 7660s ic
      1 78L15 regulator
      2 1n5817 schottky-diodes
      3 10uf electrolytic cap
      1 220uf electrolytic
      1 51r resistor

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    2. Btw. If you are a complete noob to building effects, you might consider building a smaller and less complex circuit. If you want something with high gain, there is lots of circuits with the lm386 ic. (smaller and more newbie-friendly)

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    3. Thanks dude, and yes, I should probably try something simpler just to get going but I love this pedal so much!

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  25. I understand why. Got my running just the other day and it is a hell of a pedal. High gain as shit but not so "thin" sounding like many other high gain pedals.

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  26. The pedal kind of works but it does some very, very strange things.

    There is a very sputtery, plattery velcro-fuzz-effect (not unlike what EQDs "Dirt Transmitter" does) - I believe the correct technical term is "bias starving". This gets stronger with higher notes. but overall seems to affect the signal quite randomly.
    The pedal is also completely silent when I don't touch the strings, as if there was a built in noise gate.

    Overall, the sound is actually quite interesting but more like a very heavy, crazy fuzz of doom instead of the controlled distortion I was looking for.

    Does anybody have any idea what could've caused this?

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  27. The more gain I dial in, the stronger the sputteing get and the earlier a tone cuts out (less sustain and a hard velcro like cut off of the audible tone).

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  28. Works now! Turns out, I forgot a 10k-resistor... (connects from IC2's pin 8 to the row that connects MidRng 2&3). So, if anyones interested in experimenting: the sputtery, heavy fuzz effect that missing resistor gave me was really quite interesting soundwise. Maybe one can redesign it without the unwanted side effects. Unfortunately I'm not capable of that yet.

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  29. I am new to building pedals and spend time trying to understand new cicuits but I have no Idea how the offboard wiring of this pedal will be done.It looks way complicated with all the gains,trebles,mid ranges.Can anyone tell me how the offboard wiring works?

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    1. Hey man. If you're referring to the wiring of the pots then you need to look on the layout to tell you where each lug should be connected. On the layout you'll see things like bass 1 with a wire to the board. What you're going to do is connect out 1 of the bass pot to that place on the board.

      As far as wiring the switch, neonoir beat me to it. On the offboard section the first layout shows how to wire an effect to a stomp switch in the true bypass manner.

      But, not trying to discourage you from building this effect, but I would really reccomend building something less complicated for a first build, if you're just getting into building pedals. One like this can end up quite daunting and frustrating if it doesn't fire right up and you have a build problem. Just my $0.02

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    2. Yeah I am not going to build this now.Its way to complicated for my experience.But can you tell me what mid rng 2 and mid rng 3 mean.

      Does it mean that the wire needs to be connected to the second and third lug of the potentiometer?

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    3. pot is short for potentiometers. they're the parts that have the knobs that allow you to control various characteristics of the circuit, like volume, tone, gain, etc. each pot has lugs that stick out that allow you to attach wires to. take a look at the offboard section, there's a picture that shows how to number the lugs.

      as for the "mid rng" label is the mids range pot.

      i know you said you're not planning on building this for awhile, if you're trying to learn how circuits work, about how the parts work, and how to wire things up i would focus on a pedal you're planning on building first. this way you can apply you're exact questions immediately rather then trying to apply what you're learning with one circuit to another. it can be harder to make comparisons between circuits at the beginning, know what i mean?

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  30. This site has a dedicated page explaining Offboard-Wiring: http://tagboardeffects.blogspot.de/2012/02/offboard-wiring.html

    For the Dominator you can use the first layout that is shown there (labled "Offboard-Wiring"). The 9V goes to the 9V on the charge pump board.

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    1. I get the wiring of the powersupply,but what about the pots?
      How to wire them? is there any guide like this for wirint them?

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  31. When you look at the Dominator-board layout you see those colored "wires" going off to the left and right of the board, labled "Gain 2", "Volume 1" etc. these are the wires that connect to the lugs of your potis. For example that "Gain 2" would go from the board to the middle lug of your 100k lin potentiometer. Check that offboard wiring-page for a picture with a poti that shows you on which side lug 1 and 3 are.

    If it says "MidRng2 & 3", that means that both lugs are connected with that part of the board. Best way to do this should be to simply solder that one wire coming from the board to lug 2+3 of your potentiometer.

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  32. Btw: although you can see the rows, what you see in those layouts is always the component side of the vero board (not the side where you solder). Keep that in mind when you make those links and cuts. (Yep, I made that mistake the first time... :/ )

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  33. I have built the Dominator.
    It soundet good, but it cut the sustain.
    Is this normaly or what can I built wrong?
    Excuse my terrible english!

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  34. Damn, problem solved.
    R from OPA2604 Pin 4 to ground is a 10K - I´ve used a 100K.
    Little mistake with a bad result.

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  37. Do you have the Schematic?Thanks!

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  38. hi there cant find any 51nf capacitators will a 56nf work as well?

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  39. aaaand what will be an alternative to the Bf245a? an 2N5457? or i could get my hands on an bf245c.

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    1. Hi Dirk, I would use the BF245c before I tried the 2N5457
      but ....
      try to get the BF245a because the gain (hfe) is different, I believe.

      @ ElArte, you can find the schematic on FSB, just google it.

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  40. And yes 56pf will work fine in place of the 51pf cap

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  42. Thank you very much! got the parts today aaand some nice news:
    in exchange for the bf245 i ordered the SMD-545A ( 4 pieces - never soldered an SMD - so gotta try and probably fry it) on Musikding, cause Ebay wanted way too much for them.
    What i got was the BF245A, so im pretty sure Klaus will have them in store. so i recommend to Mail him for them

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  43. Done. and the first build that wont fire up instantly :(
    cuts, bridges, parts, wiring the pots and placement seem to be right.
    But what about the Grounding?
    the offboard wiring shows in/out/switch to 9vplug ground
    and an seperate Grounding to the board.
    So do i ground 9v to Powerboard to Board?
    Each Board seperately to the 9v Ground?

    i do get the bypass signal but the effect itself wont
    start.

    Thanks in advance.

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    1. This comment has been removed by the author.

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    2. Ground is ground is ground, wire them together.
      If you continue to have problems post your voltages. That will help point in the direction of your problem.
      Will Kenworthy

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  44. Sorry Had to fix my profile. Now I'm back with the right name.
    Good luck Dirk, with your build. Any further comments I'll get an email notice & hopefully it wont take me so long to respond.
    Will

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  45. hello
    i've built this, and it worked on the first attempt!
    it seems to have a very nice sound, but i have a doubt: the mid-range control seem to affect the sound almost nothing...is this happening to all you too?even the mid control is subtle, but you can hear the difference; instead, i dont hear any difference turning the mids-range pot all the way down or up...any suggestion?

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  48. i've solved 3/4 of the problem: the mid range control now it works (matter of an unwanted solder bridge); and i understood why the sould is similar to how described by neonoir: it sounds like a heavy fuzz more than a compact dist
    i replaced Q1 with J201, and now it works great!
    it was not my BF245 faulted, because swapping the twoBF, the sound is still fuzzy, if BF is Q1; in Q2 instead, both my BF works perfectly...i could replaced both with J201 but i noticed a big drop of gain, so, i dont understand why BF245 is not good for Q1, i'll keep J201 in Q1 and BF245 in Q2

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    1. Glad you're finding a solution. I think, I'll redo mine once I have a bit of spare time. Although it worked in the end, I never properly boxed it and instead moved on to the Wampler Triple Wreck - they are both excellent distortion pedals.

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  49. i have done the wampler too...i like the sound the same, but dominator appears to be more silent...
    anyway, did you solve the "fuzzy" situation just putting the resistor 10K you forgot? nothing else?
    'cos this thing that's happening is very strange: the 2 bf245a i own both work, because putting them in Q2 make the effect sound like it was supposed to; so i dont understand WHAT's wrong...
    in this post, you're the only one that had a situation like mine, but it was just a little mistake by yours; in sabrotone.com there's a post too, an user complains about a situation like this, but doesnt explain HOW....

    P.S. is it normal that voltage at IC's is not 18v, but something less (like 15v)?

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  50. Sorry for the late and disappointing reply, crustone pippi, but I don't really have the time and skill yet to figure out what might be the problem here.

    As for your voltage question: depends on the pin. They are all OpAmps and the supply voltage on pin #8 of IC2 and IC3 should be around 18V, whereas pin 8 of IC1 should be around 15V. Without measuring, I'm not exactly sure about the voltages on all the pins but they are bound to be at least a bit lower then the voltage of their respective pin #8 ("rail to rail" voltages are always slightly lower then the supply voltage).

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  51. ok,thanx anyway...the stomp works, so i guess i should be satisfied:-)

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  53. OK.I'm having issues if anyone has any suggestions. Unfortunetly I can't take pics at this moment. I've built the trip wreck and the openhause. But my dominator has very low output. I can hear it and controls all work if I really turn up my amp. Also the level control makes an odd squeel when turned all the way down. Not really an occelating noise. Any suggestions? I've checked all cuts and traces. ICs and tranys. I am using bf245c instead of bf245a cuz that's all I had on me. I have other posable substitutions available.

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  54. ^^ Sorry I can't figure out how to sighn in to show my name?!

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  56. try change NFs with something else, andsee (hear) what happens...

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  57. i've began playing guitar again, and put out my stomps fom the dust...
    i'm playing in a punk-HC/crust band, so i need something very powerful, and the okko is what i need...but: as i remember, it has a big problem!!
    the pedal works completely fine, except for the tones, extremely full of bass!!! even turning bass all the way down, it still produces too much bass tones! someone has some suggestions on the fly??
    P.S. i used MPF102 as Q2 instead of BF245, i remember because it sounded better, but bass tones still there with both (and even others) transistors

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    1. I can't really help you out here but I'm sure that it is quite possible to filter out some more of the low end just by tweaking one or two component values. The tricky part is the lack of a schematic to work with. You'd have to create one by reverse engineering the PCB-layout and that's no fun at all, I can tell you.

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  58. for me it's not fun, it's just impossible to reverse-engineer the pcb, but even with the schematic would be undoable for me...i'm too bad in electronics!!!
    anyway, in some sites there is the schematic of the dominator!
    if it's like you said, i tried to read all posts in all forum, trying to understand which resistor/cap is the bass filter, so i can tweak it...thanx for the advice!

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  59. the schematic can be found here:
    http://revolutiondeux.blogspot.com/2012/01/okko-dominator.html
    or here:
    https://www.komitart.ru/948-okko-dominator-distortion.html
    or here:
    https://guitar-gear.ru/forum/index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=34476

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  60. it's a cool pedal...just a little problem...with a strong attack on 5 and 6 strings, the dominator's a little locked up, (choking)...sorry about my English...and it's ruining everything... please tell me where to look for the problem and how to solve it?

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  61. tried to change the input capacitor from 22 to 10 nf -- didn't help...then between 22 nf and q1 put a resistor in. (1M...Selection method)The fucking shrinkage was reduced but not completely...Is it okay to cut the signal so much? Damn... For a month now, I can't bring the pedal to mind... Any help...

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  62. reduced the input signal (r2 to 100 kOhm) everything works as it should)))....hurray...

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