Tuesday, 21 September 2010

Catalinbread Merkin Fuzz

Info about the original:

The Catalinbread Merkin is a fuzz pedal that's just 'rite' for classic sixties fuzz sounds and beyond! Extended and refined from a classic fuzz circuit, this 3 silicon transistor circuit is very textural, varying from blunt to ripping. It's controls are simple, a volume, and a texture knob with huge range, from cleanish blend counter-clockwise to full fuzz as you turn the knob clockwise.

When developing the Merkin, we chose components for sweet yet buzzing tone which still has a very touch sensitive response. The Merkin is also very responsive to your guitar's volume and tone controls so you can spend less time stooped over your pedalboard, and more time actually playing. Along with a slew of sixties fuzz sounds from the Ventures to the Stooges and many points in between, The Merkin Fuzz is able to do octave-up sounds by using your guitar's neck pickup with the tone rolled off. It works great for bass too.

The life-blood of a fuzz is its power supply and the Merkin is no different. Use a carbon battery for warm vintage tone and smooth response. Use an alkaline or 9 volt dc supply for a harder sound, or run on 18 volt DC supply for even more output and an aggressive sound! Volume unity for the Merkin resides around 9:00, which means there's lots of boost on tap.





Updated 20/3/14.  A slightly more compact version:



43 comments:

  1. Oh, nice... thanks for posting this.. I think I might build this next.

    Now my only question to myself is "did I put 2x linear 500k pots on that futurlec order?"

    I bet I didn't *faceplam.

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  2. just checked... 2x log 1x lin

    typical!!

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  3. 500K log may be ok for the volume, give it a try and see what you think of the sweep. Or you could use a 250K for the volume if you've got one. It may be a bit brighter in which case you could up the 100nF cap to a 220nF but just have a play.

    Told you to get 5 of everything! :o)

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  4. haha, yeah, I'll get around it.. I'll probably just use a log for the volume, I'm sure that will be fine.

    lol, I bought 3 of everything in random A and B types. I don't think I've every used a 500k lin pot before, probably why I only bought 1.

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  5. Aah you probably haven't got a Meathead making addiction like me then! :o)

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  6. Just built this, sounds good.

    I used 470k lin for tex/vol and I had to sub two 22k resistors in series for the 47K ones as I forgot to order them properly. Still sounds good - do you think these would make any difference?

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  7. 470K to 500K and 44K to 47K are both within around 6% and so closer than you may expect out of components with 10% tolerances, so I wouldn't worry about it. I often use 470K pots in places where schematics call for 500K.

    Thanks for confirming the layout.

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  8. Having trouble with mine. I dont seem to be getting output from the 3rd gain stage. Any schematic with this?

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  9. These are my voltage readings. Still trying to figure out whats wrong here. My layout seems to be spot on.

    2n222A
    C B E
    Q1 .63v .56v 18.8mv
    Q2 .65v .56v 18.8mv
    Q3 1.76v 1.34v .76v

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  10. I found my problem. The 47k into the base of Q3 was inserted incorrectly and I tied into the emitter which broke that stage. Works great now. I'm sure with most new builders you run into problems building so patience is key.

    Thanks for these layouts. I will try some more. This one really sounds great and glad I gave it a try.

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  11. Excellent, glad you got it sorted.

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  12. I know this is a basic question, as I'm looking at this possibly being my first build, but what do the black lines and red dots in boxes represent? I recognize the rest of the board, but just want to know since I've been really wanting one of these pedals for a while, and know a bit about circuitry already.

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  13. The black lines are just links between tracks and the red square/dots are cuts in the tracks. You can just use a drill bit and twist it at the appropriate place to make the track cuts.

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  14. Just made this up, Discovered I only 3n3's (2n2's on order) so I've put that in... I've not tried it yet so Though I may as well check in the meantime.

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    1. P.s, my typing is fricking terrible!

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  15. Just boxed it and tried it.. sounding kind of as it should but what the effect of me putting a 3n3 instead of a 2n2 be?

    It seems to be kind of 'boomy compression' at times?

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    1. It forms part of the texture circuit, with the 3n3 there should be slightly more bass content in the fully counter clockwise position of the Texture pot.

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    2. Ahh that sounds about the effect I'm getting.. I'll replace it with a 2n2 when they arrive. I think it'll sound better.

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  17. I was having trouble with this, only getting a loud swooshy sound with no guitar signal. First i thought it was because i substituted a 5n6 for the 4n7. Then i tested my 2n2222a's and found i had a Q3 with an hFe of only 27, so i swapped it for one with an hfe of 80 and now the circuit works fine. Thanks for posting this layout.

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  18. I just put the circuit together and it's sweet! Good addition to my fuzzes. There is some slightly violent character to it that reminds me of FF, but it's meaner in some way. Nice build though. This will get boxed in my next boxing frenzy i'm sure :)
    +m

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    Replies
    1. And so i did. I'm calling this one "Puzzy". There's some hair on it...
      http://mirosol.kapsi.fi/varasto/boxes/Puzzy.JPG
      +m

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  19. I'm having an odd issue with this, It all works perfectly BUT when I release my hands form the strings I get bad noise similar to a grounding fault? If I touch the metal part of the jack on the guitar cable it stops? I've tried a different guitar cable and it reduces the noise a lot but you can just hear it slightly still... It's all grounded as ground all the effects I've done so this is a little strange

    Any ideas?

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    Replies
    1. Did you try grounding the in and out with a shielded cable? sometimes higher gain pedals get noisy and the only way to quiet them down is by proper shielding, metal enclosures and even shielding the pots wires. Shorter cable lengths and and clean builds are a must.
      I will build this one in a few weeks and see if I get similar issues.

      Good luck. Sounds like a really good addition to any fuzz collection.

      Doron

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  20. Gathered a few, tried 2n5088, 5089, 2222, and MPSA18
    definitely need to put MPSA18.

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    Replies
    1. Wow, a girl builder?

      Apart from Devi and Frantone who make their living building this stuff, I've never heard of a female builder...

      Or maybe I'm just living under a rock...? :)

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    2. Goran: :D You must be...

      Ekaterina: Did you ever get the reverb to work?
      +m

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    3. No, never achieved, I think this project is to collect later
      http://www.diystompboxes.com/smfforum/index.php?topic=99803.0

      Maybe not a lot of girls. in Russia have not met anyone ((
      My latest project
      http://cs410219.vk.me/v410219967/76cb/0N4tAyQ_Pmo.jpg
      Great Destroyer+Bland+Clari(not)
      No picture, but added an optical sensor.
      You can choose between the optocoupler modulation control and sensor.

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    4. None around here either, I guess there must be more than a few up north... :)

      Bland? I know a GD and a Clari but not this one?

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    5. OK let's see, just guessing here... only two footswitches, ten knobs. Five for Clari, four for GD, is the last one blend between the two?

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    6. Really cool looking build! Must sound like a monster! Blend for that is a good idea. Adds a little usefulness to it. Clari and TGD are pretty overwhelming circuits...

      Anderton's Stage Center reverb has been on my to-do list for quite some time.. The problem is the bipolar supply. I could take that on at some point..
      +m

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    7. clean blend.
      a mix of pure sound and TGD
      what do u mean "overwhelming circuits"?

      http://tagboardeffects.blogspot.ru/2012/05/negative-voltage-inverter.html
      would it solve the problem?

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    8. By overwhelming i mean that those are not subtle effects :) Both of them create hellish racket :)

      Yup. Voltage inverter would do it - or using two batteries. We have one of those circuits already (ETI Fuzz/Struzz), that i drew and didn't notice the bipolar until Madferret pointed it out :)

      Are you in a rush for that circuit? (I have my desk pretty full at the moment...)
      +m

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    9. I don't want anyone to rush)
      gather when you have some free time)

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  21. Hi and thanks for this, I love this page!
    I've soldered this one but I just get a very quiet overdrive sound from it... Can't find any mistakes in the build so I checked the voltages of Q1 to Q3 and found (in Volts):
    Q1 C 2.88 B 0.51 E 0.01
    Q2 same as Q1
    Q3 C 7.8 B 0.66 0.15
    Could somebody maybe measure on his merkin (I mean the pedal...) if these are okay? They seem to make sense to me? the last transistor probably is meant to do a clean boost of the signal, so for that it should have the highest linear swing possible?

    Thanks in advance, any help is appreciated!

    John

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  22. Buff!! Just build this morning, it's amazing!!! The texture pot it's totally useful, my new favourite fuzz!!

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  23. Everything worked fine on this pedal. I brought it to a guitar shop for them to try out. It was fine for a few more days then the 100uf cap blew. Any suggestions on why? 9volts running all the time. Also the led light wasnt working but after the cap blew it worked after a jiggle on a ground wire. I jiggled all wires before cap blew and no dice on led light but all else worked. Polarity was correct on all caps too.

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    Replies
    1. If the cap blew without you putting in a reversed polarity power supply then it could have been a dodgy cap. But there are obviously other issues if the LED wasn't working and it certainly sounds like you have an intermittent connection on one of the ground wires.

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    2. Okay. Here is something. I brought the pedal back and replaced the cap. The pedal worked but the led was off again. At home I was using a cge ac 9v 1amp adapter which the pedal works but the light is off. I then brought it too another shop and he used a 1spot 9v 1700millamp adapter. The same adapter as the previous guitar shop. with that one the light worked but the pedal was barley audible. I luckily brought my cge adapter. The pedal worked great but the light was off. What could this be? Thanks

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  24. ...too many radio interferences...how could I solve this problem?
    and is it normal that the texture pot add volume when is turned clockwise?
    would the transistors be matched?
    thanks in advance :D

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  25. Just ran into this thing for the first time. Sounds amazing in the demos. I'm gonna give it a shot! Definitely has that fuzzrite feel to it.

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