Thursday, 2 February 2012

MI Audio Crunch Box V2

[27th May 2014 - Revised layout posted]

Info about the great sounding original:
The Crunch Box Distortion is my take on the high gain British. The history of the Crunch Box actually goes back a few years. I came up with the design after careful study of the way that modern British style amps get their overdrive. I found that there was a very big concentration of the frequency information in the midrange. So I started to experiment with different prototype ideas, until I settled on a design in late 2003. Since then, various prototypes were sent out for serious road testing, and the final design was released in early 2006.

The first batch of Crunch Box Distortion pedals sold out in record time. Within 3 weeks, my initial batch of 500 were sold. Since then, I've consulted with many users, and their feedback has been used to further tune this amazing pedal. The latest Crunch Box is better than ever, and will continue to be, I am sure, the most popular pedal that we make.







115 comments:

  1. Tag it!

    Whoah. For those who have built ZW44 or any other disappointing "distortion" should turn their heads to this design. Amount of distortion will not disappoint you here, in fact, if you find this to be too clean (which i doubt), you can replace those 100pF caps with links. That will make it a lot noisier.. I experimented with those, and left 100pF on the board. Although anything from 47pF to 1nF would work - and change the tone quite a bit.

    It's not as cold as distortion plus, but not as massive and compressed as Sonic. And it's loud. Oh boy it's loud. Think trash metal.

    I tried it with 20K trimmer, but can't really see the point using it as a trimmer. Presence is nice addition to more conventional tone control, so if you're building this, i strongly suggest that you consider replacing it with external pot. You'll just need to leave out furthest right side link and cut. Wiring goes: lug 1 to the 7th row, lug 2 to vol 2 and lug 3 to tone 1 (and 2). That way you'll have more control over the colour of the tone. This leaves enough space for onboard resistor for on led - i used row six.. You could fit it to row one as easily.

    One other topic of consideration would be using the clipping leds (which are meant to be anode and cathode on upper side and another anode and cathode on the lower side) as auxliary external leds. They light up very nicely according to how hard you hit the strings.

    It's very good and yet simple design. Probably my favourite distortion at the moment.

    Cut furthest on the left? (i omitted it), and leds should probably have + signs. Otherwise, great, no, perfect layout as always!

    Thanks Mark once again!
    +m

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    1. Ha ha, phantom track cut. I do that from time to time when I put in a cut expecting to put something else on the same row, and then do it a different way and forget to remove the cut. I'll correct it and do a version with external presence too. This is also one of my favourite distortions, I've still got an original on my board. 6 to go! :o)

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    2. I need to say one more thing about it's sound. Open and clear. While distorting like hell. Great design.

      And great modifications to the layouts. Vince! You need to build this!
      +m

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    3. I may well do Mirosol, but I built the original a while ago, Very nice I do agree but I'm finding it hard to beat my ZW44 boosting my dirt channel.

      I'll no doubt build it though!! ;o)

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    4. http://mirosol.kapsi.fi/varasto/boxes/cruncher.jpg

      I was wondering why i always use english in all control descriptions as it's not my native language. So. This time i'm calling level "voim." (short for "voimakkuus"), tone "sävy", presence "tila" and gain "särö" (which would more accurately translate to distortion than gain - but i guess that's still a better word..)

      I took the clipping diodes outside and it looks really mean in the dark! If anyone is interested in buying my Sonic in a BB, i'm selling :) Finally there's a distortion that beats Sonic..
      +m

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    5. Excellent, you need to start a 50th build thread! :o) And thanks for all the pics, my collection is growing!

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    6. Don't need the cut furthest on the left, the one below the 22k resistor ?
      I started building this today and already made all the cuts according to the diagram!
      Also want to have an external presence pot, so I need to cut the link beside IC 5 and make jumper for the cut beside that link?
      Or, is the diagram shown the revised version?

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    7. That was based on the old version, you need all the cuts shown in the Rev 2 version above

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    8. That's great, thank you.
      One more, could I off board wire the presence pot to the same 3 points the trimmer is connected?
      Btw, successfully built the Sucker Punch and the Caveman Drive, both sound great and worked on the first power up!
      Working on the Crunch box and Red Snapper now, expecting the same great results!
      Thanks for an excellent web site sir !

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    9. Finished the crunchbox! Great sound! I installed the led's so you can see them, but they don't light up, they obviously work because I'm getting great distortion from the pedal. I know they are supposed to shine when playing,

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    10. they might not be getting enough of a voltage swing to cause them to light up a lot. for instance, i've done a few keeley style DS-1 mods, which included a switch with an led in place of the stock diodes. i usually mount them by drilling out the "O" in tone so you can see them light up when you play. the thing is they really only light up when you really play hard, otherwise it's usually a very low glow or sorta flickering with the distorted tone, if you get what i mean. for me that's fine cause when i use mine i usually really dig into the strings, and the bass seems to hit the circuit harder then my guitar.

      see if they light up when you really play hard, if it lights up, you're good if not, something could be off somewhere. but if it sounds good, i wouldn't worry too much.

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    11. Thanks for the reply Johns, concerning the LED's, they don't light at all, except, when I plug into the input Jack, they flash on then off very quickly, in time with when the cable plug would be hitting the 2 ground points.
      I used one of those 3pdt wiring boards from guitarpcb.com, wired the battery ground to the RING lug of the Jack, wired the other ground to the SLEEVE lug and took that to one of the grounding points on the 3pdt board.
      Now the weird part, if I continue to plug and unplug the cable, the LED's stop coming on, like they have lost power or something.
      I wonder if maybe an elec cap is draining thru the lights due to some funky short somewhere.

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    12. you lost me man. you used a 3pdt board to wire the clipping leds? cause that could be the problem. all you need to do is have the led's anti-parallel on a separate piece of vero, and have two wires connecting each end of the led's to where they should on the main board. i can make a quick layout if that would help, as i'm not sure that came out as clearly as i meant it to.

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    13. No, the 3pdt board is for the on/off of the pedal, the only led that connects to it is the pedal on/off led.
      I have the circuit led's connected to the main circuit perf board,
      I mentioned the board because it has 7 ground points one could use as a suedo star ground scheme.
      But like you say, it's no big deal because the pedal does what it's supposed too, and that is sound great, which it does!
      The led thing would just be cosmetic anyway,

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    14. Are you sure about pot connection ? Lug 2 To vol 2 (output); lug 1 to 7 row; and lug3 To tone 3??

      Thank you

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    15. I'm not too sure about your interpretation there, Volume 3 doesn't go to Tone 3 ?!
      But the layout is definitely correct, as per this schematic

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    16. Hello IvIark,

      Thank you for help me.

      I only read what Mirosol said: " lug 1 to the 7th row, lug 2 to vol 2 and lug 3 to tone 1 (and 2)."

      But in the Scheme the trimmer lugs (T1, T2 and T3) must be connected to:

      T1 - 6th row
      T2 - Vol3
      T3 - Tone 1 and 2

      That is it ???

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    17. Miro's comments were about the original revision of the layout, the one now posted is a more compact second revision

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    18. About the presente trimmer, I did not listen to any huge difference while I was moving the trimmer. I used a 10k log instead of the log rev... Is there any alternative to this rev log pot??

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    1. Yes no problem. You can squeeze 22 columns into a 1590B if you file a bit more from the sides of the vero (although 21 is preferred), so 17 columns will leave plenty of space at the sides.

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    2. Thanks, this is my first time using vero.

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  4. i built rhis one yesterday. IMO, it's a very nice hi-gain distortion pedal for guitar, but it had too much mids and a lack of low end for use with a bass. i ended up modding mine (i'm a bass player) to give NO low end loss, installed an 18V charge pump so i can run it on 9 or 18V (18V is smoother, tighter and more dynamic), and installed a 3 way clipping switch to switch between 3mm green leds, none, and mosfet (2N7000) clipping. it's a great bass OD/distortion now.

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  5. Hi, I finished this Crunchbox(ext. presence)today,sounds great !Its my first one with vero -one thing that confused me is the different symbols for the caps so I just used what I could get hold of.Is there a chart or could someone tell me what the different symbols for caps stand for ? Cheers ,Torpy10

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    1. Hi,Tryed this out for a couple of hours today and really like it.Great agro,loud dirt pedal.A couple of minor things I noticed wrong were :
      1. In true bypass when volume pot is turned down, no sound ,also sucks a bit of tone when Volume is up in true bypass.
      2.What could I add to circuit for anti pop when switching on/off.
      Any ideas ?,thanks.
      Oh also with question about caps above,I'm cool with values just not with the coloured symbols for different cap types.
      Cheers.

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    2. How have you wired the switch? If the volume pot is still working when the pedal is bypassed then you must have wired the volume pot after the switch. If it was before the switch then in the bypass position the volume pot would also be out of circuit.

      For anti pop add a 1M resistor between the input wire and ground. You can do this on the switch if you can't fit it anywhere on the board, between the lug going to the board input and the ground lug for the LED.

      I use a ceramic symbol (orange) for values under 1nF, polyester symbol (maroon) for values 1nF to 1uF and electrolytic symbols (2 tone blue) for values over 1u, because that is what I would use for each vallue range.

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    3. Hi IvIark,thanks for the reply,
      -with the 3pdt terminals horizontal and numbered 1-3 across I've copied your offboard layout,except term.5(centre)goes to input on vero(green wire).Term.3 which is output has nothing wired to it.
      The volume pot has term 1 to ground on vero,term.2 to output tip and term 3 to term 2 presence pot.
      The LED is wired through the vero where it says LED and back to term.1 on 3pdt.
      Thanks for the help on the other 2 questions.
      Cheers

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    4. Got it,had to wire volume pot to output lug on 3pdt.Now its a true ,"true bypass".All finished now.That was good fun and now I have a cool new dirt pedal on my pedal board.Wiiiiiicked !

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  6. Hi Mark, the diodes are 3 or 5 mm?

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    1. It doesn't matter, use whatever you've got.

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  8. Built it and it sounds great!
    The only issues I have are that it seems a little too "nasal" or "honky" sounding, which I can kinda work out by playing with the tone controls, and it seems like it doesn't have much compression or sustain at all. I was testing it on a jazzmaster though.

    What could I change to get less nasaly clipping & a broader frequency range? i.e. more high sparkle

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    1. aah, I played it some more, now it sounds very gated, I have to play really hard to get anything out of it.

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    2. It seems like if I leave it unplugged for a bit it comes back to life. But then fuzzes out after a few minutes. Is this a capacitor problem?

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    3. It seems like after unplugging it for a bit it comes back to life, only to fuzz out a few minutes later. Is this a capacitor problem?

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    4. As soon as I turn the effect on the LEDs go out.
      My power adaptor is supposed to be 9v but it's putting out 11.2
      Here's what I'm reading:
      IC
      1. 4.93
      2. 4.96
      3. 5.30
      4. 0
      5. 5.30
      6.constantly changing between 1.90-3.10
      7. 11.02
      8. 11.24

      left LED
      + 1.43
      - 0

      Right LED
      +1.51
      - 0

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    5. Just for the record, I did finally get this working. I think it was the solder I was using, it was old or something. I re soldered all the joints with brand new solder and it now works perfectly!

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    6. Excellent, glad to hear it Mike. It's awful sometimes trying to debug a build, particularly when it's something you don't expect like this because it's so low down the list of things to check. Anyway at least you know now and have it working.

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  9. Hi Mark, et. at.,
    I recently completed this build and the results were absolutely stunning and massive! The voicing of this pedal is such that when using high gain and playing two notes at the same time, you can actually hear both notes clearly and not a blur of indistinguishable sound. In fact, this pedal sounded a lot better than my expensive Wampler Pinnacle, and replaced it on my pedal board.
    I made the pedal such that it could run at 18V as well as 9V, but honestly did not notice much difference when running at 18V, so for convenience I’ll just run it at 9V.
    I made three trivial changes to the layout:
    1) I added a 2M2 pull down resistor to ground at the input to prevent any clicking when engaging the pedal (which worked perfectly as the pedal switches on and off silently);
    2) I added the 1N4001 diode at the power source for protection which can be seen on the schematics;
    3) I used a 25K external pot in place of the 20K trim pot for the presence (I don’t think they actually make external-style pots in 20K, but maybe I just didn’t look hard enough).
    Anyway, thanks to Mark for this layout and his website. This was one of my first builds, and now I’m totally addicted!

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    1. Yes the Crunchbox is one of my favourites too, I've had a V2 on my board for a couple of years now.

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    2. Out of my own interest I just checked back in my old emails and it's actually 5 years since I got the Crunchbox and it's stayed on my board ever since with nothing knocking it off for any significant length of time. Where does time go?!

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    3. Hearing is believing, so I can well understand what you say. With its small footprint and mighty sound, I might as well just nail it or glue it to my board as mine is not going anywhere either.

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  10. Hi. First of all I want to thank you for your webpage!
    This is my first vero project and it sounds great.
    First time I plugged it, I thought it was a really noisy pedal. Then I realized it was boosting my amp's volume a lot. If I match distortion's volume to my clean signal's volume it isn't noisy at all.
    My problem: with volume knob at 9 o'clock it's much louder than my clean signal and it makes the volume pot tricky to use, with a little usable range. I used a 100K lin. Anybody with the same problem? any solution?
    Thanks!
    Rafa

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    1. Linear taper may be the cause. This circuit is meant to be loud, but you could try logarithmic 100K pot for volume.
      +m

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    2. Thanks!! I will try.
      I know I said it's not noisy but I have been playing for a while now and I can say when gain is past 12 o'clock there is a noticeable hum (annoying when you are not playing) but I suppose it's normal with such a high gain, isn't it?

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    3. Don't have my box anymore, so i can't check how mine acted. But i don't recall it being particularly noisy.

      You could double check everthing...
      +m

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  11. I built this on a lark today after reading the comment regarding the ZW44, which I have been contemplating for months. I am glad I waited. I may also experiment with some switchable LED clipping, but I do like the fact that the LED's visually display the volume/gain levels during play and further react to playing/picking. For my build, I did not have an LM833, and used a NE5532 instead. I may also try a LF353 if I can find it in my stash. I also used a C25 pot in place of a C20, dont' think it really matters or affects the tone. Regarding the noise, I get noticeable hum when PT & V are dimed, and then I start increasing the Gain above noon. As dirty as it gets, I will probably never max the gain unless the other controls are sufficiently backed off. Question 1, would changing the gain pot to B250 help or is my electronic ignorance showing. Second question, which 100p can be changed to reduce the bass filtering, I assume it is the one across Gain 1/2. On other pedals I have built, I find that seemingly inherent hum and noise diminishes once I get everything in an enclosure/case. (It is my practice to build and test and tweak and play with the board and pot layout on a piece of cardboard before I commit to putting in an actual enclosure/case. I believe this practice results in stray (grounding) hum/noise that dissipates or disappears once there is proper and complete grounding of circuit, jacks, pots and switches.

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  12. Oh, and again, Thank you Mark and Mirosol for another great vero layout. Next on deck is EmmaReeza.

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  14. I have problems with this one, I can't make it wwork or even make a sound.
    I wired it without switch for test, double checked about everything (component placement, traces...)
    Here are the voltages on the LM :
    Battery 8.75v
    1. 4.36
    2. 4.36
    3. 4.36
    4. 0
    5. 4.36
    6. 4.36
    7. 4.36
    8. 8.75
    So basically Vcc/2 everywhere except on pins 4 & 8
    Anyone has an idea of what could go wrong here ?

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    1. The voltages seem pretty healthy. Have you tried probing it to see where the signal vanishes?

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  15. No I didn't probe it yet, I guess this will be the next step
    What voltages should I read for the leds on row 9 ?
    I have something very low like 0.05v

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    1. So I started to use a prrobe, but I'm not very familiar with this
      I have my guitar plugged in the probe, the ground to the ground of the circuit, and the tip with the cap testing the circuit beginning with the output
      http://www.casimages.com/img.php?i=13032406014185855.jpg
      I surround all the connctions on the vero where I have sound in the amp, including IC pins 6 and 7
      I only have clean sound on all these connections
      http://www.casimages.com/img.php?i=130324060110625638.jpg

      Any thoughts someone ?

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    2. I think you have the probe in reverse.. Guitar to board input (plus ground) and probe to amp. That way you have the guitar signal coming to the board all the time - and the probe sends it to the amp.
      +m

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    3. Ah Ah right, makes more sense that way.
      Will do and let you know, thanks !

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    4. I started to probe it from the input. I follow this schematic : http://1.bp.blogspot.com/-0zGoV3jSwJs/TyKL3gQsCqI/AAAAAAAAAvs/s1ZwxhpG0WU/s1600/miaudiodistv2rx7.jpg
      Until IC pin2, I have signal, but very attenuated, I really need to push the amp to ear it. Then on pin1 I have normal sound
      Between C4 (0.1µf) and R3 (10k) on the schematic I again have this very attenuated signal, and nothing on pin7

      I built 2 boards at the same time, both behave the same.
      Maybe it's just that circuit that is not for me :p

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    5. Pffffffffff
      I don't know how but I managed to pack 470R resistors with the 1M
      And guess what ?
      Yeah, on both circuits I had 470R instead of 1M, you bet I had no sound
      Both work great now, and sound awesome
      So much time lost...

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    6. Good to hear you solved it!
      +m

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    7. Yup and thanks for the help.
      The lesson is...always verify your resistors values before soldering

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  16. Finished this today. Didn't work right out of the gate - no sound at all. Everything looked good on inspection so I popped out the LM833 and tried an opa 2604 and a TL072. Both worked fine. All 3 of the 833s didn't work - guess they're all bad.

    Is this pedal dependent on the LM833 for the signature sound? I listened to a lot of demos before building this and mine doesn't really sound that much like the clips I listened to. Mine is kinda high gain but not as much as described here and on the clips. Plus, it is pretty dark sounding. I have to have the tone and presence full to treble for it to just be not really dark.

    Measured all components before soldering so I'm fairly certain all values are as they should be. I know the sound is dependent on guitars and amps used, but most of the clips I previewed were fairly consistent regardless of the guitar and amp used for the demos.

    Just curious if the IC plays a big role in the sound in anyone's opinion. If not, I'll just rebuild in case I goofed it somewhere. Any feedback is much appreciated.

    Thanks!

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  17. Rebuilt the board. Glad I did. Don't know what I did wrong in the first build. Now I see why you guys like this so much. Quite a beast - can't believe all that comes out of so few parts. I'm trying to find something about it that I don't like, but for the life of me, I can't. New favorite high gainer. The external Presence control is a nice addition to the tone control. I can turn the tone up for some bite, but dial back the presence a bit to control fizz. Thanks for the layout.

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  18. G'day all!! I'd like to use a three position switch(on-off-on) for different diode options eg: LED(stock),Ge and Si. Do I just need to connect one side of the switch to row 9 and the other side to ground?
    Cheers, Jason.

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  19. Fresh from the tip of the soldering iron. I took the clipping LEDs outside so they blink as I play.

    https://lh4.googleusercontent.com/-y5oDNXZQiR0/UcMwq1BHCsI/AAAAAAAAA7g/jIXhuZVH2IM/w579-h772-no/CB2.jpg
    https://lh3.googleusercontent.com/-uzEd_y4na5s/UcMwrwClExI/AAAAAAAAA7c/-xx3WfSWjeU/w467-h771-no/CB3.jpg
    https://lh6.googleusercontent.com/-6qg2PiuEoSU/UcMwolobURI/AAAAAAAAA64/8nhFE8scW7Y/w444-h772-no/CB1.jpg

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  20. Can i use 10k linear pot or log... Is necessary reverse?

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    1. You could go with linear. The sweep may not feel as good as with rev. log, but it'll work just the same.
      +m

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  21. The dash ( - ) side of led diode is the negative " cathode" ?

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    1. left led is : top - bottom +, and right top + bottom - ? please help? and about the orange color?

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    2. I build with orange led..and tl072 for testing (I wait order of my lm833 from eBay)my sound is very very weak distortion with gain in max! My led diodes no lights flash when I playing guitar..i try to reverse the led + - ... Where's my fail?

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  22. I built this one today. Absolutely awesome!!! My second CB, but the first using this layout. Fired up straight away!! I took the diodes off-board onto a on-off-on toggle. LED's in the middle, 1N34A's and 4148's on either side. The only problem I'm having is that there is some oscillation when the gain is maxed. It's only on the two outside diode selections. The LED selection is fine. It's not a big problem but I was wondering why it's only on the other diode options?

    Cheers, Thommo.

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    1. It is because your clipping gets louder with additional diodes when compared to LEDs. Try 100p-220p cap parallel to added diodes.
      +m

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    2. Thanks mirosol! I'll try that asap. I've done this diode config. before and didn't have a problem with it. That one was on a May Queen distortion.

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  23. JOHN KALLAS: I have this pedal and am interested in doing the three mods you listed below. I have a question on the first one you mentioned: What component changes did you make to reduce the low end loss? I can handle the diode switching and charge pump. (I'm pretty sure)

    John Kallas wrote: "i built rhis one yesterday. IMO, it's a very nice hi-gain distortion pedal for guitar, but it had too much mids and a lack of low end for use with a bass. i ended up modding mine (i'm a bass player) to give NO low end loss, installed an 18V charge pump so i can run it on 9 or 18V (18V is smoother, tighter and more dynamic), and installed a 3 way clipping switch to switch between 3mm green leds, none, and mosfet (2N7000) clipping. it's a great bass OD/distortion now."

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  24. I ended up just putting a BMP tonestack in right after the diodes. I had to adjust the components in the tonestack calculator to make due with the stock 10k pot. (this was a Joyo knockoff, so I couldn't use a replacement pot.) Worked out great. The EXTERNAL presence control version is recommended. When you find a setting you like, and then change the distortion, you will want to change the presence. It isn't a set it and forget it value. I ran a new pot out the side of the Joyo. It's a much better pedal now. But I was afraid to pull the LEDs because the JOYO board has very thin and fragile copper. I had to run a new wire to reconnect some damage I caused during my work. Easy to break traces.

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  25. Is that 1M for anti-popping? If not, where/how do I add one to prevent popping? Thanks!

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  26. This thing caught me by surprise. I've read craploads of praise about this pedal but didn't believe before I tried. Sounds surprisingly much like my JCM800 2203 but there's like twice the gain on tap. No need for boosters with this one. It also cuts the bass enough for me to throw the tube screamer out of my board. I used to boost my JCM with a TS9/TS808. Well.. no need for that now to be honest. I put the Marshall for sale :D

    It's bright and shrill like hell but hey, that's how the JCM is too. DEFINITELY do the presence knob as a pot, it's a very useful control. I keep the presence and tone both at 9 o'clock and it's still very in your face. The tapers are fine, it's just THAT bright.

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  27. Just finished this one, although my layout of V2 must be an older one, as it doesn't have the current protection diode or the trimpot.

    Anyway, it fired up first time... after I'd found that I'd incorrectly placed a cap and a resistor. Thanks a lot, it's a nice small layout that sounds great.

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    1. Thanks for verifying the updated layout. V1 of the Crunch Box didn't have a presence trimmer so maybe your layout was based on that schematic.

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  29. Hi, Mark! I would like to ask you something. I made my crunchbox based on this project: http://www.efekty-diy.pl/pdf/Crunch%20Box.pdf that is simillar to your layout.
    I bought good quality parts (except pots, they are cheap), made my PCB using toner transfer (my first time, damn good) and soldered all parts according to that project. Worst thing is that I couldn't find any rev log C pot (im Pole, in my country it is difficult to find this, don't know why), but I made it by adding resistor to 50K linear pot (found tips here: http://www.geofex.com/Article_Folders/potsecrets/potscret.htm) and I drew graph that shows how it's working. My graph is very simillar to this: http://www.poeticmonkey.com/ebay/resistors/10k-anti-log-pot/potentiometer-types.gif so I think that my DIY Rev Log is working good. But to the point: my crunchbox sounds very very muddy, I must set Presence and Tone to the max settings or sound is very low and very quiet. Even I set those to max it sounds so muddy. I tried to experiment with pots and capacitors, but I'm not good at electronics. Can you check out that project and give me a hint? Many thanks.

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  30. Just finished this one up. No idea how I missed this one for so long, but holy shit.

    Miro wasn't kidding about this being loud. When I first plugged it in to test it out, I had the volume pot about 50% and gain pot at max (of course). Neighbors are awake and pissed off now. Seriously, it is un-fucking-reasonably loud. I love it.

    After scrambling for the volume pot, I was really pleasantly surprised at how nice it sounds. With gain about 25% I had a nice Angus/Malcolm Young sound. Jacked up to max gain I was chugga-chugging with increasingly satisfying speed. This thing is versatile!

    Aside from that, it has a fantastic tone. I don't know the appropriate term for this, but I really love the sound of rapidly hitting power chords where I alternate between fretting the chord and actually holding the same pattern, but applying just enough pressure to instead ring out harmonics.. kind of a "frethand" palm mute.. with this pedal it rings out so damn pretty, very musical and sensitive. I'm in love.

    I can't get over how small and simple the circuit appears to be, yet sounding this freaking good.

    For the record, I used 3mm diffused red LEDs and while I thought I had some LM833 chips, it turns out I do not. On the basis of another poster's experience and something I heard about a Suhr Riot pedal, I used an NE5532 instead. Sounds AMAZING. I might still grab some LM833s next time I'm parts shopping, just to try it out, but I'm more than happy with the NE5532.

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    1. Yes it's a really great pedal across the board, and I too love it at lower gain settings. Maybe that's one of the reasons I disliked the OCD so much, because I bought it at a similar time to the Crunch Box but it sounded lifeless in comparison to me and just wasn't as good at either higher or lower gain settings to me.

      The Timmy is also great after it to really tweak the EQ the way you want it.

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    2. That's quite interesting because I use a OCD clone I made years ago and a Red snapper driving a Timmy (I switch on one or the other depending on the mood).
      I lack a strong dynamic british like pedal, so this one COULD substitute the OCD.

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  31. I think I have some weird problem. The LED's shouldn't be flashing when the pedal is not engaged, should they? I have no sound but the LED's are lighting up like Christmas as sson as I plug it in. May be a solder bridge or something.

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  32. This comment has been removed by the author.

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    Replies
    1. Sounds like you have a short somewhere, which will either be caused by an incorrect connection or an unwanted bridge caused by your soldering, burrs in cuts, over-hanging wires etc. You need to go over everything with a fine tooth comb, knife the gaps and see if you can spot your error. If you are still having problems post a link to a high res front and back pic of the board and we can see if anything stands out to us.

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    2. Thanks, Mark. I found the problem. This is my first stripboard build. I cut the board not thinking that image is actually the back of the circuit. So I figured i would just "mirror" the layout and be ok. Which it would have except for, obviously, the IC. So I took it out, bent the pins backwards, and was immediately rewarded by a great sounding crunch. Now I'll outboard the presence control, mess with some caps for more bass, and on to the next pedal!

      Thank you for a great site.

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  33. Mark, Miro - got any suggestions on low-end mod? What would you tweak in the first place, guys? T
    hanks for your work, 5 sucessful builds already started from zero level of competency :) the latest units - klon and dbd (the kits are superb) are my pride!

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    1. Typically the best place to start is the input and output caps. If you increase them they will let more bass into and out of the circuit respectively. Depending on the circuit you may need/want to increase the coupling caps, which are the caps between two stages of a circuit, and they act like an input cap to the next stage. But I would socket the inut and output caps on the board and experiment with difference values and see what happens, and what you like.

      If you want to change the bass response, you'll need it adjust the caps and resistors in the tonestack.

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    2. Yes you could try increase the 22n input cap, but also the 1K and 220n from pin 2 is a high pass filter, and if you increase the cap value it will lower the frequency where the low cut off begins. So socketing those could get you everything you want.

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    3. Thanks a lot johns and Mark! It looks like my beloved sonic gonna face decent competetor soon. I liked the original CB and it felt a bit punchier, but the overall sound was less full than through sd9 because of lack of lows

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    4. no problem buddy. glad to help.

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  34. Hey! The ICs that are available are LM833x, X being different letters like M, N, D, P, etc. Could you please tell me which one to use? This is going to be my very first pedal and I'm really looking forward to it. Thanks! :)

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    1. That letter tells you the factory packaging and thus, it doesn't matter which one you use. They are all the same.
      +m

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  35. Just built this. It fired right up and sounds perfect. It is LOUD. With all knobs at noon there is a pretty intense boost

    Pics:

    http://i825.photobucket.com/albums/zz176/Dub-T-123/77AD911E-650A-4D21-8B5D-D4F3395A0D16_zpsdv5xhaii.jpg

    http://i825.photobucket.com/albums/zz176/Dub-T-123/8446145D-FA68-4975-A3C0-44F2382BD46E_zpse9gzdm3c.jpg

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  36. sup guys, i need a little help. when replacing the trimmer with an external pot, mirosol said leave out the right most link and cut...is the cut i leave out the one right beside the rightmost link?

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    1. That may have been in reference to the older layout (first posted in 2012 but updated in 2014). There's no adjustments necessary here. Literally replace the lugs of the trimmer with wires to the lugs of the pot. Or add one wire above Vol 3 and just daisy chain off the other pots.

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    2. Ah yeah, that makes a lot more sense. thanks for the help Ciaran.

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  37. This comment has been removed by the author.

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  38. good morning .... just a question by question saw the JHS ANGRY CHARLIE is very similar to CRUNCH BOX but I read the review of JHS and says it comes from MARSHALL GUV'NOR but with modifications ... if you know some of the JHS ; I mean that changes in components have by far the CRUNCH BOX thank you let me know .... thanks

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  39. There's a new version named "Super Crunch Box", which has a few more switching options and maybe an internal voltage doubler. Does anyone have more info about that version? Brent Kingman has a good demo video: https://www.youtube.com/watch?v=smZmzy8fXc4

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  40. Don't know how i managed to miss this one. Its great. Used a 5532 and It seems pretty awesome as it is. Is it much different with the 833 than the others? Would like to know if its worth getting a few.
    Slàinte mhath as always.

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  41. Is it possible if i replace the tone stack with a 3 band EQ? TIA.

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  42. Sure, have a look at the Marshall Guv'nor or Drivemaster

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  43. I have assembled the pedal, and it sounds ok but the drive knob does not work. Nothing happens when i turn the knob. Any idea where to star trouble shooting? Voltage levels to the op-amp seem ok.

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  44. I have assembled the pedal, and it sounds ok but the drive knob does not work. Nothing happens when i turn the knob. Any idea where to star trouble shooting? Voltage levels to the op-amp seem ok.

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    1. This comment has been removed by the author.

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  45. I have built this circuit twice amd both have the same problem: volume drop when engaged especially on clean channel of amp. Not sure what I'm doing wrong; but I wish I could figure it out, I want to enjoy fhis pedal as mucjlh as everyone else.

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    1. Got it, both work. It was an 470k resistor that was supposed to be 470R, woops. Awesome sound, and awesomely loud..

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    2. Got it, both work. It was an 470k resistor that was supposed to be 470R, woops. Awesome sound, and awesomely loud..

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  46. mine sounds like a monster, beasting but I am having trouble taming the pop ..using all the amz/orman mods, pulldowns etc ..going to try i/o limiting R and marks 1m from led to ground as well ..its a sweet pedal otherwise!

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  47. I built mine and am loving it, the distortion is brutal and has great clarity at the same time, really great!!

    I am however finding it weird, my volume control does not work, meaning when i roll the volume all the way down, it cuts the output, but from there on the volume just stays the same, no change at all. Any suggestions please? I am using a 100K log.

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    1. The volume is 100K Linear, check it out the schematics!

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  48. Still nobody traced the "Super Crunch Box" :-(((

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