10k vs 100k expression pot for Axe II or MFC

mr_fender

mr_fender

Axe-Master
Is there any benefit in choosing a higher pot value to work with the Axe II or MFC as an expression pedal? I noticed the EV-1 has a 100k pot for expression while most others are 10k. I know any value linear pot between the two works ok, but was the higher value chosen for any particular reason? Better resolution? More linear response? Just curious. I'm about to convert a couple of Ernie Ball pedals for expression use and thought I'd ask before ordering the pots.
 
I just modded two VPJr's and used the suggested Honeywell pots from the mod thread, I think they were 100K ? Given there isn't much price difference I'd just pick the ones that are known to work well
 
mr_fender said:
Is there any benefit in choosing a higher pot value to work with the Axe II or MFC as an expression pedal? I noticed the EV-1 has a 100k pot for expression while most others are 10k. I know any value linear pot between the two works ok, but was the higher value chosen for any particular reason? Better resolution? More linear response? Just curious. I'm about to convert a couple of Ernie Ball pedals for expression use and thought I'd ask before ordering the pots.
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From a general engineering perspective, I would suggest using the lowest impedance that will do the job; the lower the impedance the less effectively it will act as an antenna to pick up unwanted noise.

good luck
boogie
 
Boogieman said:
From a general engineering perspective, I would suggest using the lowest impedance that will do the job; the lower the impedance the less effectively it will act as an antenna to pick up unwanted noise.

good luck
boogie
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Given its an expression pedal, and not sending any actual audio through it, I don't see how this would matter ?
 
As far as I know it's a simple DC voltage divider, so the pot value shouldn't really matter that much. I was just curious if 100k was chosen for the EV-1 for any particular reason.
 
Fractal uses 100k's, so they seem to work very well. I also modded 2 Ernie Balls with 10k's and it works just as well. I think it just doesn't matter ;)

But if you need another argument to help with the decision, I'd say pick the impedance which is "more common", so you are able to use them with other gear aswell, just in case. But what's more common, 100k or 10k? I have no idea ...
 
Well, it's 90K more expressive isn't it?

Probably won't matter. I modded my EB VP Jr with a Honeywell 10K linear per the old thread:
http://forum.fractalaudio.com/threads/mfc-101-with-ernie-ball-vp-jr.35300/

Works great. The Axe-FX and MFD are flexible and will take a wide range. Other devices may want 10K, 25K, 50K or more. I went 10K because seems to be common and therefore more versatile if I want to use it with other devices.
 
lqdsnddist said:
Given its an expression pedal, and not sending any actual audio through it, I don't see how this would matter ?
Click to expand...

My last comment on this. I was paid a helluva lot of money over the years as a Professional Engineer to fix signal/power integrity problems. The expression pedal is an analog input on a long cable that feeds into the unit. It is "good practice" to not introduce things like RF into enclosures in the first place because once inside, they can often find undesired paths into places they don't belong (e.g., audio sections). Fractal may or may not have mitigating design approaches in place and that's fine. I was pointing out general "best practice" and robust design. Similar information may be learned from respected noise/rfi/emi authors like Henry Ott.

Amazon product ASIN 0470189304
old but valid to this day.

I'm out of this discussion.
 
Even though I'm not privy to inside info on the actual answer regarding why they used what they used, but I'd toss a suggestion that it is what they had on hand in decent quantity, and still within the design bubble. Perhaps we will get "the" answer from those that know.

Cheers,

Lee
 
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