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Wednesday, 18 January 2012

DAM Meathead Deluxe

A few people have requested this so I thought I'd get one put together.  Based on my previous layout but with some obvious differences due to component changes.




And a mojo version for those who prefer it





Video of Geiri's build:


60 comments:

  1. No problem, let me know if you build it up and how it goes.

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  2. Hi Mark,
    are some of the trace cuts & component locations slightly different to that of a few weeks ago, or have I made a total balls up? I did this & left it as I didn't have the right trannies, I've come back to it today & my board looks different to those here now!!

    AM I GOING LOOPY???? AAHHHHHHHGGHGHGHHHHHH!!!!!!!! :0)

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    1. Ha ha, here's the links to the old files:

      http://i76.photobucket.com/albums/j6/IvIark_2006/Layouts/Vero/DAMMeatheadDeluxe-old.png
      http://i76.photobucket.com/albums/j6/IvIark_2006/Layouts/Vero/DAMMeatheadDeluxewithLEDresistor-old.png
      http://i76.photobucket.com/albums/j6/IvIark_2006/Layouts/Vero/DAMMeatheadDeluxemojo-old.png

      That'll teach me to do updates at night after Fosters! :o)

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  3. 470k Linear pot...Is it possible to use 500k instead?

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  4. Do these trimmers look ok? never used on before.
    http://www.ebay.co.uk/itm/PK-10-22K-Horizontal-Enclosed-Preset-Trimmer-POT-/140731316722?pt=UK_AudioElectronicsVideo_Video_TelevisionSetTopBoxes&hash=item20c43d79f2#ht_1160wt_954

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    1. No, those have a 10mm pitch and so span 4 rows. Try these:

      http://www.ebay.co.uk/itm/280522465869
      or
      http://www.ebay.co.uk/itm/150770279381
      or
      http://www.ebay.co.uk/itm/110827368750
      or
      http://www.ebay.co.uk/itm/260843229802

      Plenty of options there

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    2. Cheers, I see they're 20k not 22k as in the layout. Thats ok then?

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    3. This comment has been removed by the author.

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    4. Or these, UK based
      http://www.ebay.co.uk/itm/5-x-22K-0-1W-Preset-22Kohm-Variable-Trim-Pot-Resistors-/300558996518?pt=LH_DefaultDomain_3&hash=item45fab65426#ht_1156wt_954

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    5. Yes 20K is fine, you won't be setting it anywhere close to 20K (or 22K) anyway. Not sure about the second trimmers you posted, they look like they could be OK in the pic but the spec doesn't give the pitch. I'd just check with the seller that the pitch is 5mm x 5mm and if so they're fine. The third trimmers you posted are the vertical type and the pitch looks to be 5mm x 2.5mm to me.

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    6. Right ok mate, I'll have a hunt. I'm going to do this one so I'll be back at some point with a hopefully successful update.

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    7. In case anyone else needs them, the seller tells me these are 5x5mm
      http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=260979479197&ssPageName=ADME:X:RTQ:GB:1123#ht_500wt_970

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  5. Hi mate, Have all the parts for this so I'll be attempting it soon... Could you please explain where I take wires from and to for the external bias pot? I've accidentally deleted the email.. (I'll be making both internal and external)

    cheers mate.

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  6. Not getting anything from this one... bypass is fine.. effect,nope.

    I just get buzzing etc when touch the back of the circuit and thats it.

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    1. UPDATE:

      Sorted, I had a short in the circuit.. VERIFIED and sounding nice... the trim pot turns it very gated and spitty so I think an external one will be cool.

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    2. Excellent, thanks mate

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    3. No worries, don't forget to tag it verified :)

      This is a good read for people as some might think the deluxe is not acting as it should (Filter adds bass clockwise/Attack jumps to full on at the end of the sweep)All normal.

      http://www.stompboxes.co.uk/Deluxe.html

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  7. Looking at some of the originals they have chassis ground connected from the input.What exactly is the purpose for a chassis ground?..Is it just a safety measure if the jacks should come loose or??.Would´nt it be easier to just connect input and output?.

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    1. It just means there is a solid ground connection to the box, but as you suggest, you will get this by grounding the sleeves of the input and output sockets. Some people prefer grounding the chassis because they feel the connection made by the input and output sockets isn't secure enough. Whilst there may be something in that, I've never had a problem with it in any stomp box.

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    2. Ok.What is the box connection physically made of?..Is it just a zinc screw through the box connected to a piece of wire?

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    3. Oh wait..Those closed jacks used are they insulated??...If so one would have to ground them to the box?

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    4. I've no idea what Dave uses to be honest with you, but if they are insulated he'd need to attach the sleeves to ground by wire

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  8. Finished this tonight with an external bias pot....So much better that way! allows you to fine tune it much easier than the internal...

    Not convinced it beats the original Meathead though.

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  9. Just finished wiring, sounds great as a D*A*M is supposed to. I used a 33nf input cap as I prefer the "Dark" values, and wanted to try something not so extreme as the 390nf I used for the Meathead with switching caps.

    I used the settings that David tells: Volume as "Dirt", attack fully cranked and tone at 12 o'clock, and you get a clasic Meathead.

    For what I can see, this effect is very similar to the Drag'n'nFly. The input trough Filter pot is just the same in both with the only difference is that the MH uses a 1uf cap and the Drag a 10uf.

    While in the Meathead, the filter knob works great, and just modifies bass / treble, in the Drag affects the whole tone and the more CCW you turn the knob, the more hollow, weak and sputter the sound gets. Maybe I should check the Drag as never liked this behaviour and now I see it's not the way it should work.

    BR

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    Replies
    1. Cuál sería el capacitor de entrada? 4n7? Yo también quiero los valores "oscuros" jeje... Gracias!

      Which one is the input cap? 4n7? I also prefer the "dark" values. Thanks!

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  10. Mark, another question :P

    I've been taking a look to other Meathead de Luxe veros (as I've not been successful finding the schematics), and on other veros, like the Revolution Deux (http://revolutiondeux.blogspot.com.es/2012/01/dam-meathead.html) as an example, I miss an 1M resistor.

    In this vero appears between the Filter 3 and the trimpot, and i'm not sure of the function it runs.

    Can you tell me anything about?

    BR

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    Replies
    1. It looks like a mistake on beedotman's layout. Another layout I found shows a 1M pulldown resistor at the lower input cap, and I suspect beedotman's is supposed to be a 1M pulldown resistor at the 1u input cap, but he put it to the second row instead of the top ground row. Making it's current connections shown in the layout on Fred's site doesn't make sense.

      You could always include a pulldown resistor to ground in any effect that you're getting popping, but if you're not I wouldn't bother.

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    2. Thanks Mark, supposed so too as could not find any reason for this resistor connecting Volume 3 / Filter 3 and the trimpot, but prefered to ask first.

      I've finally soldered a 4.7nF as stated, instead of the 33nF i put first, because being an input trough the filter pot I assume that you get all the values from 1uf trough 4.7nf, isn't it?

      I hope tomorrow to start boxing this effect, as while I really love the Meathead with switchable caps, I think that the de Luxe is just the same but with many more options if you want.

      Until I tried Dave's effects, never liked silicon fuzzes, but I've learnt that you can get incredible fuzzes at a fraction of their germanium cousins.

      BR

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  11. What are good substitutes for the transistors? I guess the 2N3904-BC182L combination found in the standard meathead would do (as well as the BC182L having the same pinout as the BC108B)?
    Thanks! :)

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  12. Hi,I built the deluxe model and it works great,I like the filter/tone pot, its good.I used 2N3904 and BC107 trans,sounds good to me.Left the bias trimmer inside ,prefered to tune up and close the lid.
    A minor error on the onboard LED layout,on the cut/link layout theres an extra cut,its the lower one just left of the link.I did that cut and found that signal dosent get to 100nf cap and thru Filter pot and to output so theres no sound.Easy to fix but, solder a link over cut.
    Enjoying this Fuzz pedal, thanks.

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    Replies
    1. Thanks for the heads up, I corrected the layout

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  13. hi, i have problem i built it but no sound...i dont know what to do...

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  14. built this one today and it sounds very nice. i do have two versions of the BC337's but i think that the 2N3904 sounded better in mine for Q1 so i'm going with that. i didn't have any BC107B's and BC109C's have too high of an hfe so i used an NOS 2N2369 (hfe of 120) for Q2 and it sounds great. i might order some BC184L's and BC107B's just to give them a try in Q2 but i doubt that it'll improve it.

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  15. tried the BC184L's and the BC107B's and I prefer the 2N2369 for Q2, and got it completed this afternoon. it sounds great.

    PICS:

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/DAMez/MDeluxe-01.jpg

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/DAMez/MDeluxe-02.jpg

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  16. I finished the DAM Meathead Deluxe, it works! But the attack pot respond only in the last quarter and before it whistle. any idea?
    The trim pot what change ?
    Sorry, my english is bad :)

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    Replies
    1. I used a 25K trim pot and pot 1K LIN for attack.

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  17. hi, i started with soldering electronics from almost zero and i finished my first project in a etched box last month. it looks pretty beaten up. have a look at https://www.facebook.com/bratislav.methulsky

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  18. I built this two times with no success. I have built more complicated stuff before so I don't think I could have messed it up twice.

    The first time I built it, I noticed that my 100n capacitor was rated at 630V.
    Then I decided to re build it with the same parts that I carefully desolder and this time I used a 100V capacitor but same results, no sound at all.

    I have triple checked everything and made continuity tests with a DMM...everything is damn fine.


    The only "sound" I notice is when I turn the trimpot almost all the way up, I got a tiny noise, similar to the noise you get when you have a scratchy pot. But that's all I can get out of it.


    What can be wrong?
    Could I have damage a component the first time I used the 630V capacitor?


    Thanks in advance for any suggestion!

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    1. it doesn't matter at all what the voltage rating of the cap is, so that's definitely not it.
      it seems that you either have an error in your build (i.e. wrong or misplaced component, or a bridged solder connection (short) to me.

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    2. I don't think I have any error in the build nor bridged solder connections. I will upload some high res pictures.

      I think I will re build this with entire new components a 3rd and last time. I built the regular Meathead a few weeks ago and I loved the sound, but I would like to have a Master volume so I decided to give this a shot.

      Thank you so much for replying John!

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  19. This comment has been removed by the author.

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  20. Quick note for anyone who buys BC107B's in a plastic "TO-92" format. I bought some for this build and realised after hours of head-scratching that the pinout is different. The Base and Collector are the opposite to the layout above - in the case of the type of BC107B's I bought. Before I did that, it worked, but it was all very clean with no fuzz effect. Cheers.

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  21. Hi,

    how do I change the layout in order to have the following differences:
    - implement a switchable cap
    - remove attack poti & trim poti
    - implement a low pass filter

    Thanks

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    Replies
    1. It sounds like a regular meathead is more up your alley, and a low-pass filter is incredibly easy to implement

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  22. I finished mine and really love it !
    I went for BC108B's but it sounded extremely similar to other BCXXX's combinations. I used an external bias knob wich I find usefull.

    Pics of my build - with a blendable octa-fuzz (EQD Tentacle) in front of the Meathead :
    https://imgur.com/a/Rqylz0y

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    1. Also many thanks to the commment from OutlandStudiosNI about the the BC10X's pinout. I got confused for a while before figuring I swapped the base and collector for Q2.

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  23. Hi all ,Would I get away with a 33uf instead of the 22 or should i go lower value

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    1. Try a 10 or a 33uf in there. Using the 22uf almost all frequencies get amplified except extremely low frequencies. 33uF will amplifier even lower, 10uf raise the frequency when amplification starts. But in all cases we're talking about frequencies lower than you can expect from a guitar so I doubt very much you'll get any audible difference.

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  24. Hi all , Would I get away with a 33u instead of the 22 or should I use a different value , Used my last 22 in the crazyhorse .

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  25. Built today & works great! Thanks for posting! I had to use a 20K trimpot but dimed it to get sound (feel like it could go higher if I had a bigger trimpot). Also subbed out Q1 and Q2 for a 2SC1815 and 2N2222a since I didn't have the right ones (tried an MPSA18 and 2N2222a). Used sockets so I may swap out if I get the matching transistors. Overall happy that it fired up right away and it was a pretty simple build. I've had a couple recent demoralizing builds that didn't work out so it feels good to get a win!

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  26. just completed the meathead dlx, sounds so nice but when I crank the level and attack to 14.00-15.00 position, it gets oscillation.. any tips to fix it? thanks.

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