Understanding output in live situation

  • hi all

    I plugged in my kpa, connected to a 4x12 marshall cab. It sounded great. What i don't know: when cab sim is off in the output menu, why do i hear a difference in the sound when i switch the cabinet button on and off? I thought it was supposed to bypass monitor out? But then again, output is the only tutorial i cant find and the manual is not very clear to me. Thanks for your help

    once a purist, then analog pragmatic and finally a digital believer who found out that you can't hear a mosquito fart in a band-context.

  • It is supposed to bypass the cab section. I just double checked on mine and it works as expected so it looks like something isn't set right.

    In your example it should say Monitor Cab Off ticked in Output menu pages 1 and 3 (they are both linked so ticking/unticking one should automatically change the other). Is that correct?

    Is it a powered Kemper or are you using an external power amp?

    If external amp which output(s) are you using?

    Which cab are you turning on/off? If you have the cab in Stack section engaged but toggle the On/Off in the output menu you are actually adding the cab to the monitor which would change the sound.

  • why do i hear a difference in the sound when i switch the cabinet button on and off? I thought it was supposed to bypass monitor out?

    If I'm reading this correctly, you were thinking that Monitor Cab Off meant "mute the monitor output." That's not what it does. It disables the "speaker cabinet simulation" of the profile. Think of it like this...

    Profiles have both the amplifier section and also the speaker cabinet section. So normally, if I'm in the studio for instance, what I hear coming out of the L/R mains is the combination of the amp going through the speaker cabs. When you have full range studio reference monitors, or an FRFR speaker cabinet, this is a Good Thing because it paints the entire picture of the sound.

    No matter what non-Kemper amplifier I plug into my 4x12 Marshall cab, the speakers will contribute to the overall sound. That's fine if I sit a JCM 900 on top of the 4x12. Amp + Cab = Rock and Roll.

    However, when you sit your Kemper on top of the 4x12, what you're getting is Profile Amp + Profile Cab + Physical Cab (Marshall 4x12) = Not What You Expected.

    In this case, the profile is running the virtual amp through a set of virtual speakers (whose color contributes as you'd expect) to get the sound you like. Coming out of the L/R main, that's all you get and it's still Rock and Roll. But coming out the monitor, you're coloring that sound a second time by running it through the 4x12, i.e. a second speaker cab.

    So, the rule (er, more like guidelines) is if you're coming out into a power amp / physical speaker, turn Monitor Cab off so you don't get two layers of speaker cabs. But even with that off, you'll still get Profile Amp + Profile Cab coming out the mains to FOH, so this is intended to give you what you want to hear on stage (hence "monitor") without affecting the "studio quality" sound that goes to your main mix.

    That's pretty long winded, but I hope it helps!

    Kemper remote -> Powered toaster -> Yamaha DXR-10

    Edited once, last by Chris Duncan (December 20, 2018 at 11:28 PM).

  • thanks, i didnt expect mute but the cabinet button colors the sound. Is there something in the rig manager i can do to search for amps without cab? I know my cab will color the sound. But still, a 4x12 just sounds amazing :)

    P.s. by cabinet button i mean the stack cabinet button in the middle. That is coloring my sound. But i dont understand why?

    once a purist, then analog pragmatic and finally a digital believer who found out that you can't hear a mosquito fart in a band-context.

  • As I mentioned earlier this shouldn't happen.

    The way the Kemper works with cab emulation is that it tried to guess which part of the sound is Amp and which is Speaker. It has no way of knowing exactly where the signal path separates so needs to apply some sort of estimation algorithm. It generally does a pretty good job but it can occasionally throw up some unexpected results.

    Your idea about looking for cab free profiles in Rig Manager to eliminate the cab and test for the cause is sound; look for any profile that has Direct/DI/D in the title. Also look for Merged profiles. Direct have no cab while Merged acurately split the signal to separate the amp and cab by comparing two individual profiles..

  • that was helpfull, thanks. I'm gonna try this out.

    I try to remember to write the findings and settings down in detail afterwards. Its hard to search for something if you don't know how to name it :)

    Much appreciated

    once a purist, then analog pragmatic and finally a digital believer who found out that you can't hear a mosquito fart in a band-context.

  • when cab sim is off in the output menu, why do i hear a difference in the sound when i switch the cabinet button on and off?

    It all depends on how your cab is connected to the KPA. You can disable the cab sim for the monitor output in the output menu. But this leaves the cab sim on for the other outputs. So in case your cab is connected through the main outs the KPA's cab sim is still available through the main outs. That's why you hear a difference when switching the cab button within the stack section on and off.

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

  • I have the powered rack version, i connected the cab with the speaker out and have cab sim off at monitor path. Its not a big concern, it is a missing piece in understanding the signal chain of the kemper.

    Some amps sound better with the cab on in the stack section and some better when the cab is off.

    One question remains open: what do you hear at FOH when i deactivate the cab in the stack section? just the amp no cab?

    Thanks

    once a purist, then analog pragmatic and finally a digital believer who found out that you can't hear a mosquito fart in a band-context.

  • It is supposed to bypass the cab section. I just double checked on mine and it works as expected so it looks like something isn't set right.

    In your example it should say Monitor Cab Off ticked in Output menu pages 1 and 3 (they are both linked so ticking/unticking one should automatically change the other). Is that correct?

    Is it a powered Kemper or are you using an external power amp?

    If external amp which output(s) are you using?

    Which cab are you turning on/off? If you have the cab in Stack section engaged but toggle the On/Off in the output menu you are actually adding the cab to the monitor which would change the sound

    I have the powered rack version and i'm turning cab on/off in the stack section but also have cab off in the outputmenu.

    The original rig comes with a cab - so from my understanding, this rig is sent in full to main out, but the cab part is turned of for monitor, if cab sim monitor off is checked. - with that setting, i can toggle the cab button in the stack section and have (sometimes) a very big difference in sounds from the monitor.

    once a purist, then analog pragmatic and finally a digital believer who found out that you can't hear a mosquito fart in a band-context.

  • The way the Kemper works with cab emulation is that it tried to guess which part of the sound is Amp and which is Speaker

    I think this quote maybe nails the reason for what you're experiencing. If you're working with studio profiles the influence of this guessing approximation can be more or less obvious.

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

  • I have the powered rack version and i'm turning cab on/off in the stack section but also have cab off in the outputmenu.

    The original rig comes with a cab - so from my understanding, this rig is sent in full to main out, but the cab part is turned of for monitor, if cab sim monitor off is checked. - with that setting, i can toggle the cab button in the stack section and have (sometimes) a very big difference in sounds from the monitor.

    that really should not happen!

    I noticed this behaviour when the amp is switched of, support gave feedback that in that case it is “as designed”...(though strange from my perspective), but If im correct they also gave feedback that it shouldnt happen when theres an active amp.

    What id do...make a video and send it to support.

  • Thanks for the advice. I will play around a little bit more with the settings first and then send the video to support.

    once a purist, then analog pragmatic and finally a digital believer who found out that you can't hear a mosquito fart in a band-context.

  • Stumbled over this thread as I noticed something simular and really strange. This got me worrying about something i thougth my kemper did manage well. Turns out it don't.

    I was checking out a DI profile from Reampzone (RZ_PRSMT15_D09) and without any cab added, it sounds great trough a V30 cab. Now, i wanted to add a cab sim aswell. Turns out, with the cab sim, and checked for "Monitor Cab Off" , it sounds different trough the V30 cab. It's not much, but some of the dynamic and high end is cut. Suddenly it sounds more "fake" trough the cab. Even if monitor cab is off. So i tried to then turn of the cabinet button. And it still sounds fake. If i go back to the original profile, with no added cab, it sounds great again.

    So the thing is: even with a DI profile, whit "monitor cab off", the profile changes when i add a cab sim. Must say this worries me. Is there something im doing wrong?

  • Stumbled over this thread as I noticed something simular and really strange. This got me worrying about something i thougth my kemper did manage well. Turns out it don't.

    I was checking out a DI profile from Reampzone (RZ_PRSMT15_D09) and without any cab added, it sounds great trough a V30 cab. Now, i wanted to add a cab sim aswell. Turns out, with the cab sim, and checked for "Monitor Cab Off" , it sounds different trough the V30 cab. It's not much, but some of the dynamic and high end is cut. Suddenly it sounds more "fake" trough the cab. Even if monitor cab is off. So i tried to then turn of the cabinet button. And it still sounds fake. If i go back to the original profile, with no added cab, it sounds great again.

    So the thing is: even with a DI profile, whit "monitor cab off", the profile changes when i add a cab sim. Must say this worries me. Is there something im doing wrong?

    ''without any cab added, it sounds great trough a V30 cab'' So thats the way to go... Personally when it sounds good, thats the way I go. If it sounds bad otherwise with a different adjustment... I don't wanna know why I swich to the good sounds and forget all the rest