Volume pot replacement
Nov 23, 2001 at 4:03 AM Thread Starter Post #1 of 4

CaptBubba

Not dumb enough fora custom title...so he thought.
Joined
Jun 30, 2001
Posts
1,615
Likes
11
Well, I'm replacing the burnt-out pot on my amp. I am replacing it with the cheap alps pot for radio-shack, because that's what's in there right now. But, I was wondering, because non-log pots are more linier than log pots in geneeral, wouldn't it be possible to put a resistor across the input to ground and that would make the linier pot act more like a log pot, with the added benifit of increased liniarity?

I was bored, so I drew up the following graphs. From what I see if it is correct this configuration would act just like a log pot. Here's the equations I used:
Red: y=((1/x)+.2)^-1 (pot resistance input-ground w/ 5K resisor in parallel)
Blue: y= 10-x (pot resistance input-output (10K pot)
Black y= Red(x)/Blue(x)

Anyway, sould this be a good alternative to a log pot? One potential advantage of this setup is that if I lower the value of the resistor in paralell w/ the ground the slope gets much less steap, meaning to me that the volume would raise at a lower speed, making the pot more sensitive. That was one problem that I had with my current pot, it would get too loud, too quick. Would this help?

I may try this anyway just to see how things turn out, because hey, a linier pot is only a few bucks, and if it works, it would be worth it.
 
Nov 23, 2001 at 4:17 AM Post #2 of 4
Here is a fun link I've posted before on the subject:

Pots

ok,
erix
 
Nov 24, 2001 at 11:25 PM Post #4 of 4
Well, I gave it a shot, kind of. RS doesn't carry dual ganged linear pots, but I got a single one and hooked it up to one channel. It's markedly better than a log pot, or at least the cheap alps one from RS, and considering how cheap the linear one is compared to expensive log pots, hmmmmm.....

With the alps pot I can hear when the different resistive layers are reached, because at the end of each one the volume seems to increase less per unit of rotation, then it hits the next resistive area and it increases more naturaly for a bit, then does the same thing.

But because I couldn't find a dual-deck linear pot, this alps one will do for now, but I will recomend that anyone who has a relitivly cheap log pot give this a shot, as it sounds more natural and is only a few bucks ($2-3 for the pot and $0.30 for the resistors).
 

Users who are viewing this thread

Back
Top