Author Topic: Digitech XP400 - replace potmeter with resistor  (Read 1457 times)

bccrew

Digitech XP400 - replace potmeter with resistor
« on: February 12, 2017, 08:20:47 AM »
Hello all, I'm new to this forum and kinda new to electronics in general. I'm the lucky owner of a Digitech XP400 Reverb pedal. I have been using it for years now and it still works like a charm.
The only thing that always bothered me was the "Input Level" potentiometer. The potmeter is a W100K so I guess it's resistance is 100 ohms. I always leave the know around 40% open. I have been reading up on potmeters and have watched a few YT video's about them. If I understand correctly I need to remove the potmeter completely and replace it with 2 resistors.

One between L1 and L2 and again one between L2 and L3.



Is this correct? How would you guys take on this project?

Thanks for your input!
« Last Edit: February 12, 2017, 08:31:16 AM by bccrew »

digi2t

Re: Digitech XP400 - replace potmeter with resistor
« Reply #1 on: February 12, 2017, 08:14:37 PM »
It's 100Kohms (100,000 ohms), not 100 ohms. The W represents the taper, which means how the resistance will sweep through the range of travel.

What exactly "bothers" you about the pot? Does it not function properly?
Dead End FX
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bccrew

Re: Digitech XP400 - replace potmeter with resistor
« Reply #2 on: February 13, 2017, 04:11:39 AM »
Hello, thanks for your reply. The problem is that I would like to exclude all volume or input levels out of my pedals and arrange every setting on my amp.

At the moment the button is unreliable when it comes to friction of cables, transportation of my pedalboard..etc

digi2t

Re: Digitech XP400 - replace potmeter with resistor
« Reply #3 on: February 13, 2017, 06:31:23 AM »
Removing that pot isn't worth the trouble. Besides, if your soldering skills are shaky, you just do damage to the board, not to mention any static can possibly damage an IC during handling.

Here's a better idea; If memory serves me correctly, I believe the pot shaft has a cap on it, which is the part that sticks out a bit from the casing. You can pull this cap off the shaft. Looking at your picture, the cap end where the step is. You can use a pair of side cutters from the outside to GENTLY grip this cap, and pull it off. The pot shaft will still be sticking out of the casing. Grind the excess off with a Dremel, and put a piece of duct tape over the hole (once it's set to the desire volume, of course). That way, you won't run the risk of damaging anything internal, and there will still be enough shaft left to remount the knob if you decide to sell the unit later.
Dead End FX
http://www.deadendfx.com/

Asian Icemen rise again...
http://www.soundclick.com/bands/default.cfm?bandID=903467

"But nobody wanted crystal clear solid state with ample treble other than like, The Partridge Family."  - pinkjimiphoton

bccrew

Re: Digitech XP400 - replace potmeter with resistor
« Reply #4 on: February 13, 2017, 08:09:33 AM »
Good idea :) thanks