Posts by heldal

I have one that is equally old which also has started acting up, but a little different. Mine doesn't shut down, it is just the front-panel that goes inactive every now and then. There is LCD-backlight, but nothing else is working. The LCD is blank. I can't even shut it off with the chickenhead knob. It can be controlled with the remote and is producing sound, but I have to pull the plug to turn the KPA-head off.

However, I've found that the problem disappear for a couple months if I upgrade the firmware or reload the release that I am on. Could it be failing NVRAM causing corruption of code that is happening on older units? I'm just speculating, but that could cause all sorts of random problems. Have you tried to upgrade or reload firmware?

Great. Front-panel controls are much more useable with firmware 8.7.6. Previously turning knobs was like .. nothing ... nothing ... nothing ... everything. Small adjustments took a lot of patience to get right.

Quote

- Main out Kemper (XLR) straight in the X32 inputs (Stereo)

- X32 BUS (stereo) in to my In-Ear and from there wireless to my receiver en UE 11Pro

When I use the Cab instead of the IEM I use the Jacks mail out in to my Custom Transistor Amp and from there in my Cab. All stereo as well.

Assume you mean "main", not "mail" there

This explains your problem. You are sending the same signal to the PA as the one you are sending to your amp and 4x12 guitar-cab. That means that the effect your amp and cab has on the sound do not apply to the PA.

The better way to do this is to :

1. use monitor-out into your amp+cab, and main-out to into the PA.
2. Set cab emulation off for the monitor-outputs in output settings. Also set monitor to stereo and connect direct-out to your amp for a stereo
3. Disconnect main-outs from the master volume in output-settings to enable adjustment of monitor volume independent from what you send to the PA. At the same time you can also enable the 10dBm output reduction for the main outputs. That will stop most audio-techs from complaining that your KPA's outputs are too loud.
4. Re-adjust the rigs you use on the KPA so that they again sound good through the 4x12. (Now without cab-emulation in the KPA)
5. If the emulated cab in each rig now has characteristics similar to your physical cab, then you should achieve a very similar sound through the PA (which still has cab-emulation active).

With rigs in the KPA that use an emulated cab very different from your physical cab then you may struggle to make the PA sound the same. One amp into two different cabs can be almost like two different amps. The cab colors the sound a lot. This is why most people seem to prefer to use a neutral monitoring solution and keep cab-emulation on for both monitor and main outputs.

Does your guitar sound OK through the PA-speakers? If it does, then the problem is with the mix in the X32. If not, then is CAB-emulation on in the RIG(s) you use on the KPA? Assuming you use a powered KPA to feed your 4x12 I suspect that you are missing CAB-emulation for the signal going to the PA. You wouldn't be the first not to read the manual and/or not explore the output options and still get great sound through a traditional cab by turning off cab-emulation in the stack, only to discover that the signal going to the PA sounds bad. The correct way to do things when using a powered KPA (or unpowered KPA some external amp) into a cab for monitoring is to keep cab-emulation on in the stack for each rig but turn it off globally for monitoring in the output settings. That keeps cab-emulation on for the main-outputs. The signal going to the power-amp in a powered KPA is the same signal as the one going to the monitor outputs. If the emulated cab in each rig you use has characteristics similar to your physical cab then you may get similar sound in the PA (and your in-ears) to what you hear from your cab.

Quote from JAC

How about a browser-based application to access the Kemper over the network? It would automatically be usable by any system running a modern web browser. Linux! Android!

We actually had that in a Beta prior to the launch of the Kemper Remote. It was a web-app emulating the remote with display and switches. At that time the KPA would happily attach to your house-network grabbing an ip-address from the local DHCP-server. The problem we have at the hardware-level is that the Kemper Remote, if you use that, require power over ethernet so you will net a PoE-capable switch when the Remote can not connect directly to the KPA. It is some time since I last tried to hook my KPA up to my network so I don't know how well it can coexist with other gear today. The core of the unit is network capable so there's at least opportunities for interaction between the KPA and RM as well as for example audio over ethernet (DANTE/AVB).

Quote from BayouTexan

Most likely you have some corrupt files which happens from time to time using databases. Deleting the corrupt file is all that is needed. Doing a factory reset can work wonders, but I would check with Kemper Support before doing this. Make sure you backup your important files first. It is nearly impossible for computer components to fail that do not have moveable parts like a IDE hard drive, switch, dial, etc. You have to take a hammer or put them in a fire to break them. I have an Atari 2600 that works like when it was purchased in the 80's.

Database corruption is not something that just happens every now and then in a database, or any storage for that matter. It is always caused by some kind of failure in software or hardware. The KPA performs some limited consistency-checks during upgrades, but there is a need for more. Especially as the hardware is getting older. There should be a consistency-check available in the menus that checks both firmware and data. My KPA had a rather serious issue with the front-panel being seemingly disconnected at random. LCD backlight was the only sign of life although the unit was working fine with the remote. Even the power/mode-switch wasn't working so the only way to regain control was to pull the plug. The problem disappeared after upgrading to the current production firmware. Nobody else had reported similar symptoms, which make me suspect a glitch in the NVRAM where the firmware is stored. I had been running the same firmware for some time without problems when the issue first appeared so it wasn't simply a bug in that particular firmware. A simple checksum validation of NVRAM-content could have pinpointed the problem immediately.

My Kemper's 10th anniversary is coming up so I'm also starting to be concerned about maintenance. Warranty ended years ago and shipping such old gear half way around the globe for expensive repairs isn't reasonable IMHO. Maybe the community should create and maintain a list of things to do and how, what tools are required, possibly with instruction-videos etc. The most obvious things being tasks such as cleaning the internals and replacing circuit-board batteries.

Quote from deigoruellez

This is so useful, thank you! Would you say it's abnormal to bring your own monitoring cab to a large venue? Wouldn't they have their own system (wedges, etc.)? Would it be because you prefer your own? Like I said earlier in my post, they had wedges for us but it just sounded terrible and I could barely hear anything.

Like those who use their own regular amp I prefer a rig I know how will sound. In addition there are other factors that may require a powerful rig. It is for example hard to execute techniques that require controlled feedback without a rig that actually move some air. Backline for monitoring is still normal in addition to the venue monitoring-system, except for a few situations that require minimal stage volume like for example some live TV/radio-events. I have occasionally used the venue-monitors for guitar, but in most cases both I and the sound-engineer prefer that I use my own and only get a general mix of instruments and vocals from the house-wedges. With the KPA I do not need to play as loud as a tube-amp for it to sound good anyway.

I'm considering a Kemper Power Kabinet as an option to my current monitoring solutions to cut weight for travel to rehearsals and smaller venues. When standing close to the Kabinet I see a need to use the stand to slant it upwards. Will the KPA head still sit securely on top, or will it fall off? Does anyone have experience with this combo yet?

That is the BlueAmps Conehead 212

Whatever rocks your boat I always go XLR-stereo to FOH, but tend to vary my monitoring based on the type of gig/venue. For the big venues and occasions where an old-fashioned backline is used I've got a Blueamps Spark (2x10"/2x250W top + 12"/500W sub) full stack. These days I would probably have chosen a Kemper Power Kabinet instead. Might still get one because the Spark is a heavy beast to travel with. For small venues I may use a single wedge instead (Dynacord AXM 12A). Occasionally for tiny events I operate the PA from the stage, and in this case the only reasonable solution is in-ears so that I can hear approximately the same as the audience.

Btw, the workaround I and others have suggested by powering on to tuner still produce a short burst of audio (<1sec) before the tuner mute kicks in if there for example is a cable with no guitar plugged into the KPA. It shouldn't be that hard to make power-up a silent process.

It has been suggested to implement a set of selectable global input settings that could compensate for varying instrument characteristics. The 4 soft-buttons above the display are unused in input settings and could potentially be used to provide direct access to 4 different sets of parameters, alternatively one button to enter a list of many alternatives ... then select with a knob. I think there is room for improvements in the input section, but so far it has not been prioritised.

Quote from BayouTexan

Ohhh. Shouldn't it start in whatever position the pedal is in? So, if pedal is heel (off) then the Kemper should know that and vice-versa. I've never noticed it being indifferent.

That would be nice, but the KPA has no way of knowing the position of a pedal attached to the remote before the network-connection between the KPA and the remote is established. Power to the remote is delayed until the KPA has completed its boot-cycle, so there is a significant delay until the remote has completed its diagnostics and boot-process and is ready for operation... And even then the KPA doesn't register the pedal-position until the pedal is moving.

Would it be possible to add an output option to make i possible to set power-up-volume (pedal) to 0. It is rather irritating to have the unit blasting away for the seconds it takes to get control with a locally or remote-connected volume pedal. It is of course possible to power on to tuner with the tuner set to mute, but that is easy to forget. And then there is the occasional power-loss. If implemented as an option in output settings that defaults to off it will not affect those who use the KPA with no pedals.

Quote from MehlAnoma

Bump same problem. I have found if i dont use remote it does not seem to happen. But still it is a pain sometimes I will use kemper pause to edit something on track in that time it craps out. Dont really want to have to ship it to Germany to get fixed. Would be nice if its a battery problem we could do it ourselves?

Do you mean that the KPA front-panel dies if you don't use the remote, or that the remote (display and/or LEDs) stop working?

This thread is about problems with the KPA front-panel. Btw, my KPA-head has behaved just fine over the last couple weeks.

Battery may become an issue soon as my unit was assembled in 2012. An expected lifetime of 6-7 years has been mentioned elsewhere on the forum. There is no warranty after 5 years so I may just as well check if I can locate and replace any batteries inside myself. Unfortunately the manual doesn't list the type(s) of battery required. I'm aware owners are not meant to replace batteries on their own, but I have the required tools to work on PCBs and have yet to be defeated by batteries on any old gear no matter how well the batteries have been secured/glued/soldered to PCBs. Gear that is meant to last should IMHO also be designed so that battery replacement is a simple task.

Over the past couple weeks the front panel on my KPA has stopped working 5 or 6 times. Not while playing, and I have yet to observe it happening. It doesn't matter what is connected to the unit so this is definitely a different problem than this thread originally was about. I have tried backup, reset, re-flash, restore with no result. Unless it takes a turn for the worse I will wait to see if the next firmware update changes anything. If not I will have to check the wiring inside. Does anyone know anything about the expected lifetime of these things? My KPA wasn't built yesterday. It is from when the dark front panel had just been introduced. Was it 2013?

After running for a few hours with only audio in and out connected I hooked up the remote and deliberately let it run over night. Now, more than 12 hours later it is still running normally. Strange as it only yesterday didn't run for more than max 2 hours before the front-panel would give in, and that was without RM connected. The KPA-side of the USB-cable was plugged in, but with nothing connected at the other end that should not matter.

Quote from BayouTexan

With the way power companies push out crazy voltages and spikes during the day, I make sure to turn mine off when not it use for longer than 30 minutes. I always cringe when the lights begin to flicker and my profiler is on.

My wife leaves her computer on all the time. The problem is, she is always asking me why its locked up the next morning and mine is working fine -- it's because I turn mine off when I sleep (except the ones making crypto).

Seriously, see if it locks up on you if you start turning it off for the night. If yes, then contact Kemper Support.

Did you even read the thread? I've already mentioned that my KPA never runs over night. However, it's built mostly from components also used in industrial gear built to run 24/7/365 so it should be expected to be able to run stable for long periods of time. Around here the voltage coming off the grid is very stable, and has been for decades. In the days before online connectivity and frequent updates I could have computer-gear running without UPS continuously for months, or even years only limited by the occasional planned or unplanned outage.

Quote from BayouTexan

If you look at quoted post above, I do believe it said "days".

Ahhh .. didn't notice that. Not from me though ... My KPA is never left on over night, but is regularly on all day for practise and recording. However, its components are mostly bits and pieces also found in industrial computer-gear designed to operate 24/7/365.

While composing a ticket for support I left the KPA at the point where it stopped dring boot and after a while, 10-15 min I guess, I turn and see that the unit is UP! None of the resetting I tried seems to have worked. At least system defaults are there as my master volume is only connected to monitor-out the way I want it. I then power-cycled the unit with the front-switch and it booted normally.

Strange. It remains to be seen if it can be trusted again.

Now running a backup, then experiement a bit more.