Wooly mammoth part substitution

[markbee]

Hi guys, I've decided to build a wooly mammoth clone or something like that. I'm building it according to this layout

http://tagboardeffects.blogspot.com/2011/02/zvex-woolly-mammoth-vero.html

It seems fairly easy to build and all the parts are easy to get, except the 2k linear potentiometer, Im not quite sure what can I substitute it with.
And if i substitute it with something with slightly different vlaue, what difference will it make? Or shall I adjust some other parts or something?

[LucifersTrip]

Hi guys, I've decided to build a wooly mammoth clone or something like that. I'm building it according to this layout

http://tagboardeffects.blogspot.com/2011/02/zvex-woolly-mammoth-vero.html

It seems fairly easy to build and all the parts are easy to get, except the 2k linear potentiometer, Im not quite sure what can I substitute it with.
And if i substitute it with something with slightly different vlaue, what difference will it make? Or shall I adjust some other parts or something?

it looks like it's just being used as a variable resistor, so full fuzz will be exactly the same...you just won't be able to turn down the fuzz as much

btw:
http://www.taydaelectronics.com/2k-ohm-linear-taper-potentiometer.html

[markbee]

I just found 2k5 linear potentiometer in the local store, that would be alright wouldnt it? Or is is better to use 1k lin pot?

[knurra]

what I would do, on breadboard, is put a 1k resistor and 1k pot in series.
Maybe the resulting minimum r to gnd of 1k is low enough.

But then again, I may be horribly wrong

Now I have to build it!

[petemoore]

  2k..2k5...
  This position makes the resistor a gain control, more R = less ''AC gain'' to the emitter....ie greater impedance on the "power channel" [emitter/collector of gain stage] of the transistor.
 2k5 probably gives about the same rotation = change in gain as a 2k would, just the spread will be a teeny bit 'wider' and the change would be a little more 'coarse' adjustment because the potshaft rotation spans over a slightly wider variable R...should be easy to adjust, just slightly less 'fine tuner' like and include increased 'lower gain' setting.

[LucifersTrip]

good luck

[Govmnt_Lacky]

You could always go a-la Dr. Boogie...

5KB pot with a 5.1K resistor tied across lugs 1 & 3 = ~2.5K pot

[~arph]

You can leave it out... you'll never turn it down anyway 

[Mark Hammer]

You could always go a-la Dr. Boogie...

5KB pot with a 5.1K resistor tied across lugs 1 & 3 = ~2.5K pot

+1

You can actually use pretty much any value pot.  The crucial thing is that the resistance between the 100uf cap and ground will only increase gain beyond what the 2k2 emitter resistor does if it is less than 2k2.  Now, even a 5M pot can provide resistances of less than 2k2....you just might have some difficulty finding them in the 2 degrees of rotation where they will live!

So, the objective is to use a pot value, and a parallel fixed resistance that will permit you to dial in effective resistances of <2k2.  If the combined parallek resistance you arrive at is >2k2 at the maximum resistance setting (e.g., 3k5), that will not be a problem.  If you had to turn the gain pot up to 10:00 to notice any sort of gain increment at all, that still leaves you with 10:00 - 5:00 to adjust gain, which isn't so bad or frustrating.

Having built one of these, I find the interaction of the Pinch and Wool controls interesting.  A lot of useful variation in there, and certainly something to play with for other circuits based around the Fuzz Face structure.