Joben Magooch
Well-known member
Hi all, so I’m curious if anyone has any insight here. I’m looking to use my trusty Ernie Ball VP JR as an expression pedal, specifically with my HX Effects. I’ve seen mixed messages on the matter; some folks say it doesn’t work, others say it works with reservations, others say it works with some tweaks/mods/etc, and others still just say it’s plug-and-play, no problems.
I’ve got a typical 250k VP JR. As I understand Line 6 for ages now has had their stuff configured to expect a 10k (TS, not TRS) expression pedal and values outside of that spec are hit and miss. The pot in mine was getting worn out and in need of replacement, so I figured I’d try and replace it with a 25k one; generally speaking it seems like from what I’ve gathered people have more luck with the 25k VPJR than the 250k version.
So I got the new pot installed. First weird thing is that it was seemingly operating backwards. I took photos and wired it in exactly as the stock 250k pot was, but once I got it all buttoned back up, heel-down was 100% and toe down was 0%. So that’s weird. Swapping the wires on the outside lugs got it back to normal but I don’t really know what was happening there. I double and triple checked and it was wired the same as stock 250k but just operating backwards. But anyways.
The pedal works OK as an expression pedal now. It’s detected by the HX FX and mostly works as it ought with one issue: it’s showing as 100% “on” (toe-down) roughly 60% through the sweep. It sweeps fairly smooth, but it’s like all of the travel from 0-100% is registered in just 60% of the pot rotation. It stays at 100% on for the remaining 40% rotation.
I thought per chance my pot just wasn’t seated right when I restrung the pedal but no, it’s correct…
So the next thing I’m leaning towards checking out… the 250k VPJRs have a “taper” switch to adjust the sweep/feel. There’s a 220k resistor on the PCB, and it looks like the taper switch brings it in and out of the circuit, maybe? And as I understand it, the 25k VPJRs do NOT come with a taper switch or that 220k resistor stock from the factory.
So all that to say is that I’m then wondering if removing and jumpering that resistor might sort things out? Otherwise I feel like I’ve seen where you can put a resistor across the pot lugs to tweak the “value” and so I wonder if that wouldn’t also be an option?
Anyways let me know what you think! Here’s a link to the stock 250k schematic.
I’ve got a typical 250k VP JR. As I understand Line 6 for ages now has had their stuff configured to expect a 10k (TS, not TRS) expression pedal and values outside of that spec are hit and miss. The pot in mine was getting worn out and in need of replacement, so I figured I’d try and replace it with a 25k one; generally speaking it seems like from what I’ve gathered people have more luck with the 25k VPJR than the 250k version.
So I got the new pot installed. First weird thing is that it was seemingly operating backwards. I took photos and wired it in exactly as the stock 250k pot was, but once I got it all buttoned back up, heel-down was 100% and toe down was 0%. So that’s weird. Swapping the wires on the outside lugs got it back to normal but I don’t really know what was happening there. I double and triple checked and it was wired the same as stock 250k but just operating backwards. But anyways.
The pedal works OK as an expression pedal now. It’s detected by the HX FX and mostly works as it ought with one issue: it’s showing as 100% “on” (toe-down) roughly 60% through the sweep. It sweeps fairly smooth, but it’s like all of the travel from 0-100% is registered in just 60% of the pot rotation. It stays at 100% on for the remaining 40% rotation.
I thought per chance my pot just wasn’t seated right when I restrung the pedal but no, it’s correct…
So the next thing I’m leaning towards checking out… the 250k VPJRs have a “taper” switch to adjust the sweep/feel. There’s a 220k resistor on the PCB, and it looks like the taper switch brings it in and out of the circuit, maybe? And as I understand it, the 25k VPJRs do NOT come with a taper switch or that 220k resistor stock from the factory.
So all that to say is that I’m then wondering if removing and jumpering that resistor might sort things out? Otherwise I feel like I’ve seen where you can put a resistor across the pot lugs to tweak the “value” and so I wonder if that wouldn’t also be an option?
Anyways let me know what you think! Here’s a link to the stock 250k schematic.
