Friday, 5 October 2012

ZVex Woolly Mammoth - Cut Down Version

Vince on here asked me if I could adapt my layout to make a 2 Knob Woolly Mammoth with just Pinch and Volume controls.  He wanted me to remove the Wool pot simulating it being set fully clockwise, and  remove the the EQ pot and simulate it being set dead centre.

The Wool pot was easy enough, it just takes the 100u cap from the emitter of Q3 to ground in the clockwise position, so I could connect that directly to ground.  The EQ pot was 10K and so I used two 4K99 resistors from where lugs 1 and 3 of the EQ pot would have connected, and taking the other side of both resistors to the same row simulated the centre setting.  If you want to alter this slightly just socket them and change the ratio between the two resistors, maybe try a 6K8 and 3K3 for instance if you want slightly more treble or swapped round for more bass.

I think it sounds great so I had to post it here just in case anyone else fancies making one too.  Vince's excellent demo:






33 comments:

  1. Cool ;o)...I also found that completely omitting the 220n on board gave a huge treble/fizz increase ... not bad, but not to my liking... something else to play with for someone maybe.

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  2. just tried this out...there are only 14 columns, so I have an extra in the middle :) not something I will prob ever use, but it works :)

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    1. Ha ha, I removed a column when I put the cap on the switch and forgot to change it! :o)

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  3. Man...i tried the 4 pots version, two times...now this one. just cant make it work. im using stripboards, can it be the problem? i test the circuit with just the pots, jacks and battery, without the pots...nothing happens. what i get at best was just the clean guitar sound. any tips?

    thanks in advance!

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    1. The ground on board circuit goes to the sleeve on the output jack, right? output on board goes to the tip in the output jack, input goes to the tip in the input jack, and sleeves from both jacks are conected for grounding. is this correct?

      can i send you some pics of my circuit?

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    2. you can't test the circuit without the pots. for all intents and purposes, because of the pots, the strips that have a pot lead coming from them are connected BECAUSE of the pot. it's probably why you're getting nothing.

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    3. well, at least for the pinch knob anyway

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    4. Yes Nicholas is right. Without the Pinch pot the Q1 emitter is out of circuit so it won't work

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    5. i already tried with the pots before. think its a really nice and easy project to begin with, right? damn.

      Some images could help?

      [IMG]http://i83.photobucket.com/albums/j294/ibreath/Board04.jpg[/IMG]
      [IMG]http://i83.photobucket.com/albums/j294/ibreath/Board03.jpg[/IMG]
      [IMG]http://i83.photobucket.com/albums/j294/ibreath/Board02.jpg[/IMG]
      [IMG]http://i83.photobucket.com/albums/j294/ibreath/Board01.jpg[/IMG]

      Thank you, mates.

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    6. Are you sure there are no bridges with that soldering? There are a few spots where the solder is certainly hanging over the next row and looks like it may be touching. That may want checking for unwanted continuity between tracks with a multimeter. Also some of the values look like they maybe wrong. The top right hand most resistor is supposed to be 10K, but on your board I see those colours as red-green-orange-gold which would be 25K?

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    7. To be honest, It looks to me like you probably have quite a few bridges.. if you have a small hacksaw or similar to seperate the tracks and there looks like a break in the track to the far right..

      http://oi47.tinypic.com/w1fz0m.jpg

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    8. shame on me. i switch the 20k and 10k resistors. sorry, yeah, i'll try again today and i post the results here. the begining is that hard i think. really really thanks for your kind attention.

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  4. Hi, Guys, does the ground from the 10K pot go to sleeve of output, please?

    Mark.

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  5. It goes to anything that's grounded. Whatever is neat/convenient for you. I usually just make sure my enclosure is grounded and solder the lug to the back of the pot.

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  6. Let's say this is the first pedal I'm going to take a stab at. My question is how is the stomp switch set up? if you could just tell me which legs go where, it'd be greatly appreciated

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    Replies
    1. http://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html

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  7. BC108's sound killer in this...

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  8. I really cannot make this work, i've built it twice and no fuzzy mammoths for me. Only sounds like the input signal passing straight to the volume pot and then out. The strangest thing is that whenever i connect in/out sleeves to battery ground, no signal will pass through the unit. Also then no controls are working. I want this to work so badly :(

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    1. Got it working after a fair bit of debugging, really smooth and loud!

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  9. stupid question considering the name of the pedal, but anyway to easily achieve a little less wool?

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  10. What switch should be used for this project?

    Anyone have any pictures of this thing wired to the stomp switch and toggle for a visual aid when building?

    Thanks!

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    1. Two pole two position On-On. Like this one here:
      http://www.musikding.de/Switches/Toggle-Switches/Toggleswitch-DPDT::163.html

      This guide should help you a bit:
      http://tagboardeffects.blogspot.fi/2012/02/offboard-wiring.html
      Just pretend that the input of that pseudo-board in the guide is the lug 2 of the switch and output is the lug 2 of the output pot.

      +m

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    2. Thanks for the reply! Found this offboard wiring too from the forums...
      http://gaussmarkov.net/wordpress/thoughts/wiring-up-a-1590b/

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  11. Ok guys, I need a little help. I don't have any 220nf caps, I do have 100nf caps.
    Di I put these in parallel? When I look this up online it says caps in parallel add rather than divide like resistors. Is this correct?

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    Replies
    1. Yes I think you are right. Putting caps in parallel will add while in series divide.

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  12. If I only want the less bassy input capacitor, should I go with the 220n or 22n one? Thanks.

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    1. Go with 22n, smaller caps filter out low frequencies, bigger ones let them through. It's always a good idea to socket input and output caps so you can experiment easily.
      Thanks
      Dave

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  13. Just want to say thank you.
    THis was the frist pedal I have put together and it sounds great!

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    Replies
    1. http://i.imgur.com/KhED2QS.jpg
      All I had for an enclosure was an ipod case looks kind of cool.

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  14. Thank you so much for this site. I have assembled many pedal kits, but this is my first foray into stripboard. I built two- one for me and one for a bandmate. Both builds took a bit of troubleshooting, but with the clear instructions and detailed comments I was able to de-bug them myself. Thanks again- time to try some more!

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Should all layouts be verified before publishing? This would mean less layouts but more peace of mind?