Topic: vpc1 pedal problem and fix
The following explains how to fix the flickering/fluttering issue of the VPC1 sustain pedal. The root of the problem is the potentiometer located inside the pedal unit.
A while ago, I posted on this forum about a problem I was having with the VPC1 sustain pedal. I think I've complained about this pedal unit before, too, because it feels kind of cheap. The pedals don't have the appropriate resistance found on a real piano, and seem to be shorter in length (though I haven't actually measured). I feel like Kawai cut corners here. Anyway, I'm rambling, sorry.
The specific issue I was having with the pedal unit was that it was producing a fluttering or flickering effect, shooting out erratic midi data. This data can be seen in, for example, in Logic where random 'noise' data is visible in the orange pedal line in the piano roll. More importantly, it can be heard, especially because it rapidly triggers pianoteq's pedal sound.
I ordered a replacement from Kawai, and the issue seemed to be resolved. However, a few weeks later, the same problem returned. I called Kawai back and couldn't get any help. Finally, I decided to see if I could fix it myself.
Turns out to be pretty easy to fix (and I'm that guy who doesn't know how to change a flat tire). The hardest part is taking the pedal unit apart. Take the screws out from the bottom. You have to get to the green circuit board. However, at some point, you will get stuck. You'll see a black box, but can't get it out. There is a black plastic bar that you have remove first. It's tricky to remove it. The bar goes across the unit and has teeth that snap in in between the pedals. This bar basically holds the whole thing together. Once you get the bar out, the rest will easily come out.
Now that you have removed the circuit board from the casing, you need to locate the potentiometer. Press on the sustain pedal, and look for a tiny moving part in the top right corner of the board. It's a (black?) cube. Inside it, you can see two surfaces rotating against each other. It's hard to see it moving unless you really look carefully. But it's in the top right corner of the board. It's two tiny circles sliding against each other. There is a very small amount of space between the two circles. If this surface gets dirty, you start to get erratic data. Take some WD-40 or similar oil and spray a tiny drop between these two circles. That's it. Put it back together, and it should work perfectly. I haven't had any problems with the pedal unit since doing this. It works great now.
If you need more clarification, I can probably help you. It's actually easier to do it than to explain how.
