Home › Forums › Help/Technical Questions › Little Big Muff Mod question: decreasing gain

Viewing 11 posts - 1 through 11 (of 11 total)
  • Author
    Posts
  • March 8, 2010 at 12:09 am #79994
    fingersoccer
    Member

    So I have an EHX Little Big Muff, and I want to be able to take the Sustain knob down to a more usable range. I never turn it past maybe 9 o’clock because everything after that is too over the top. Would simply changing out the Sustain potentiometer to a different value effectively change the range? For instance, instead of having full blown shredding starting at 11 o’clock, I would want it closer to 3-4 o’clock, making the usable range wider. Ideas?

    March 8, 2010 at 12:15 am #108250
    The EH Man
    Moderator

    There’s a resistor that goes from the outer lug of the Sustain pot to ground. You can replace it with a larger value if you have the tools to do surface-mount.

    March 8, 2010 at 1:04 am #108251
    Ned Flanders
    Moderator

    Try 10k-15k….. (limiting resistor)

    March 10, 2010 at 3:43 pm #108347
    fingersoccer
    Member

    OK, so the 10k-15k suggestion is for the resistor that goes from the Sustain pot to ground, right? Thanks!

    March 10, 2010 at 11:01 pm #108370
    Ned Flanders
    Moderator

    Yes.

    But decreasing sustain is just a matter of turning the knob down. The resistors not going to effect it on maximum setting at all because there’s zero resistance from lug 3 to 2 on maximum and there’s 100+k resistance to ground and the signal will take the path of least resistance…ie;lug 3 to lug 2.

    If you want less sustain on a lower setting you would actually want to reduce the resistor as the lower it gets the more signal passes to ground and if you remove the resistor all together it will ground out and become silent, hence, basically become another volume pot.

    I would put a 560 Ohm in it. Much less than this and you will have no distortion at all on zero.

    (BTW, I misread your post the first time)

    When a certain amount (I’m not sure of the actual percentage) of muff signal goes to ground it starts sounding bad as you would probably know from turning it down. IMO the muff sounds best with the sustain no less then 2 o’clock,it just doesn’t have a very usable sustain control. Its not actually a distortion control BTW,its just a pot between the first input stage which is a clean boost and the first clipping stage.

    I’ve always wondered whether it would be better having the sustain pot pre- circuit rather than after stage one. A lot of fuzz pedals have this set up, I’ve never tried it on a muff but I have been meaning to.

    The metal muff has a very usable distortion pot,it can be turned to zero and still sound really really good, its very user friendly.

    March 11, 2010 at 2:17 am #108377
    ranjam
    Member

    I might get crapped on for saying this, but it won’t be the first (or last) time, so here goes nothing. To me, and with all that eye-straining SMT ‘stuff’, if you don’t like the pedal the way it is, flip it over and get a different pedal. Mucking about with the surface mount components, if you aren’t super careful and 101% sure of what you are doing, you risk ruining a good pedal. What if you want to put that itsy-bitsy-teeny-weenie resistor back? :doh: A vintage Little Big Muff is easier, but then again you are screwing with a vintage (and collectible) pedal. I don’t see a ‘win’ happening anywhere here, and just one lose-lose after another.

    March 11, 2010 at 7:17 am #108385
    Ned Flanders
    Moderator

    Vintage LBM’s and XO LBM are totally different! Still muffs, but not the same at all.

    I do agree though ,unless you know what you are doing modding SMD is not a good idea. if however you do know what you are doing its no more of an inconvenience than modding any other pedal.

    March 11, 2010 at 7:49 am #108386
    julian
    Moderator

    here’s an easy way to do it without modding the pedal (which is a PAIN on SMD):

    Give it less voltage:

    http://www.beavisaudio.com/Projects/DBS/

    March 12, 2010 at 11:53 pm #108432
    ranjam
    Member

    My fear is that less B+ doesn’t decrease gain, but headroom. The noise may come up as well, although for the life of me I have no idea why I think that.
    Has anyone seen a real schematic for this very pedal? Not a generic ‘Little Big Muff’ schematic, but the EHX with reference numbers for the parts? Maybe you can come up with some type of easy ‘snip, snip; less gain!‘ mod.

    March 13, 2010 at 12:46 am #108434
    Ned Flanders
    Moderator

    There’s a way to decrease gain easy enough but it still involves removing and replacing resistors.
    Read my article here:http://sovtek.webs.com/bmpgainfactor.htm

    April 27, 2010 at 11:04 pm #98824
    johnlohn
    Member
    Quote:
    There’s a way to decrease gain easy enough but it still involves removing and replacing resistors.
    Read my article here:http://sovtek.webs.com/bmpgainfactor.htm

    Wowie! Very in depth article, I think it all went way over my head. You really know your stuff. I have a few old pedals that I never use and I am thinking it might be fun to tinker with them. Good luck with your mod.

  • Author
    Posts
Viewing 11 posts - 1 through 11 (of 11 total)
  • You must be logged in to reply to this topic.