Master volume went crazy

    Hi,


    while i was playing with my Kemper the master volume went crazy and the volume started to jump up and down from 2 to 7 to 5 etc.. What happened? Can you help me? Thanks

    I've had it happen on both my Kemper,s from time to time, walk up to the amp touch anything and the master volume slider pops up. It's rare and hasn't killed a show but so I didn't think much about it. Would love to hear what you find out though.

    I've had the volume drop to zero while playing before, but never go up. I've had to either reset the kpa, or more recently they put a soft button in the system menu that just resets the global variables, and that fixes it too. However, I've been reading about problems with the linking of the various outputs, so last night when it happened again, I unlinked them and the volume was restored. This is the best solution for me because I don't have to go and fix all my preferences that get reset with the other methods. Still, I don't know how people can trust in the unit live. Im just an amateur and don't play out, but I would be very leary of it if I did.

    It does sound like it could be linked to the volume linking thing, have you tried unlinking it? The volume linking bug is a serious pain in the ass I hope it is fixed soon as it drives me nuts, and seriously puts me off using the KPA live.

    Quote from Kempermaniac

    Do you have your KPA sitting on a cab? Maybe some vibrations are causing the pot to move?


    I would doubt this based on the OP's description of the problem. The fact that the knobs on the KPA are not pots but rather rotary encoders means that the KPA does not read the knobs absolute position instead it senses movement of the knob in each direction by pulses generated by the encoder as the knob moves. This also means that errant pulses sensed by the unit could be generated by a number of factors outside of actual movement of the knob including a flaky encoder sensor, or even something like bad power from "noisy" A/C mains or bad grounds could potentially cause this type of issue.


    Perhaps isolate the unit from other digital devices that might be producing interference nearby or sharing the same mains and see if that helps any. Not that you have this situation,, but large inductive loads on the same A/C circuit (like a refrigerator compressor) or other inductive loads have been know to cause issues with nearby digital devices. Hope you find a solution for this issue..

    @ mwinter77: Maybe I should have said "...causing the volume knob to move", but it makes no real difference. If the volume knob is moving due to vibrations, the pot/rotary encoder itself moves too. That's what it's made for (turn the knob and the volume is changing). If it's turned by hand or due to vibrations doesn't matter.


    The Line6 Vetta Combo had such an issue, that's why I've mentioned it.

    I could have farted and it would have sounded good! (Brian Johnson)

    Quote from Kempermaniac

    @ mwinter77: Maybe I should have said "...causing the volume knob to move", but it makes no real difference. If the volume knob is moving due to vibrations, the pot/rotary encoder itself moves too. That's what it's made for (turn the knob and the volume is changing). If it's turned by hand or due to vibrations doesn't matter.


    The Line6 Vetta Combo had such an issue, that's why I've mentioned it.


    Fair enough - I was trying to differentiate the operational model of the two different technologies to point out that the rotary encoders are going to be more susceptible to digital oddities like noise than a traditional analog pot would be. Traditional pots and analog circuits while they might move a bit and change the level due to vibration they are not likely to jump around wildly like an encoder circuit gone haywire might be. Plus I am an accuracy nut when it comes to technical discussions. :)