# Abider/Dude C25k question



## Ratimus (Sep 3, 2020)

Anyone built one of these with a value other than C25k for the"deep" control? I was going to use C20k, but the more I think about it, I'm wondering if I'm going to miss that 20% of the range. I'm not gonna buy a C25k because I'm stubborn, so it's either build it with the C20k or use an A25k and wire it backwards (so now it's a "shallow" control). Thoughts?


----------



## Ratimus (Sep 3, 2020)

Or use a B25k, or hack a C25k from a B50k...

I'll probably just hack a higher value linear pot and not have to live life wondering what I'm missing out on.


----------



## okstateblues (Sep 3, 2020)

I built the abider and used the B25k. I didn't notice any big difference but maybe I don't have trained ears


----------



## Ratimus (Sep 3, 2020)

okstateblues said:


> I built the abider and used the B25k. I didn't notice any big difference but maybe I don't have trained ears


Thanks for the heads up. I ended up faking it with a B100k pot and a 36k resistor.


----------



## okstateblues (Sep 3, 2020)

Sneaky but I like your style. I hope it turns out stellar. I really like the pedal as it's so creamy


----------



## Ratimus (Sep 3, 2020)

okstateblues said:


> Sneaky but I like your style. I hope it turns out stellar. I really like the pedal as it's so creamy


Super sneaky! Pics of stealth resistor mod included for posterity in case anybody is interested.


----------



## Barry (Sep 4, 2020)

I used a C20K, I'll have to compare to my actual Dude and see what I'm missing or not, now!


----------



## Ratimus (Sep 4, 2020)

Barry said:


> I used a C20K, I'll have to compare to my actual Dude and see what I'm missing or not, now!


The sound never really starts to open up until that last 5k. ?


----------



## okstateblues (Sep 4, 2020)

So by putting the resistor 


Ratimus said:


> Super sneaky! Pics of stealth resistor mod included for posterity in case anybody is interested.


There like you did, what does that make your pot value? 64k?


----------



## Ratimus (Sep 4, 2020)

okstateblues said:


> So by putting the resistor
> 
> There like you did, what does that make your pot value? 64k?


100k parallel with 36k ends up being ~26.4k, with a taper of about 1:3. Check out the classic article for more info: http://www.geofex.com/article_folders/potsecrets/potscret.htm


----------



## moonlightpedalbuilds (Apr 20, 2022)

Ratimus said:


> 100k parallel with 36k ends up being ~26.4k, with a taper of about 1:3. Check out the classic article for more info: http://www.geofex.com/article_folders/potsecrets/potscret.htm


Did anyone notice that the sweep goes up to ~30k before going down to ~26k at around 2 o’clock ?


----------



## pcb rookie (Apr 20, 2022)

Barry said:


> I used a C20K, I'll have to compare to my actual Dude and see what I'm missing or not, now!


Curious to ear back about the results .... I've been wondering about this for a while!


----------



## Barry (Apr 20, 2022)

pcb rookie said:


> Curious to ear back about the results .... I've been wondering about this for a while!


Well, I gave my Abider away since this post and don't really recall the result, I have another in the queue though, so I'll have to revisit it then


----------



## Lewage (Aug 8, 2022)

Ratimus said:


> Super sneaky! Pics of stealth resistor mod included for posterity in case anybody is interested.


so when you do this you are just bridging 2 & 3 with the leg of the resistor? I’ve done this when I was only using 2 legs of the pot but didn’t know if it would work with 3.


----------



## HamishR (Aug 8, 2022)

The resistor goes from pin 1 to pin 3 - not to 2. The pot is a resistor with a wiper (pin 2) sweeping across it. So by adding the resistor you are altering the value of the "resistor".


----------



## Robert (Aug 8, 2022)

Not the most elegant solution, but you _could_ use a C50K dual pot and parallel the two gangs together.

Tayda has one but it's splined shaft / PCB pin mount, so it'd take a little wiring, but it would work and would give you C25K.


EDIT: Actually scratch that, StompBoxParts has the correct part now.








						16mm Potentiometer - Short PCB Leg
					

Top Quality Parts for Guitar Effects Pedals and DIY Music Devices. Knobs, Pots, Switches, Kits, LEDs, Enclosures, Jacks, Wire, Resistors, Capacitors, Semiconductors




					stompboxparts.com


----------



## Bricksnbeatles (Aug 8, 2022)

You can create a near-perfect approximation of a C25K pot with a B250K pot in parallel with a 28K resistor (the resistor goes from lug 1 to 3). 28k resistors are uncommon, so you could either measure some 5% 27k resistors until you find one that's close to 28k, use a 27k resistor and be content with a 24.4k pot (well within typical tolerances anyway. this is what I'd do), or put a 27k and a 1k in series with each other.


----------



## Deperduci (Aug 8, 2022)

Advice for those who can't get Cusack's stuff inside a week.


----------

