wrong speaker connected

    Studying the reference manual I learned now that you never should connect an active device to the power output. Unfortunately I've done this several times, not knowing this, with a powered QSC K8 FRFR speaker cab. But lately I noticed a heavily thunder coming from that speaker while playing at a louder volume. It seemed that this 1000 W (!) cab could not handle the volume. Could I have damaged something either in the cab as well as in my Powerhead?


    This brings me to my second question. It seems that it's also possible with the Powerhead to play stereo with two cabs, just as with the unpowered 19" version of the Kemper (combined with a power amp) Therefore you would have to use the monitor out and the direct out. Is this right and does this mean connecting a non powered cab to monitor out and the other cab to direct out?
    If this is true, how to control volume for both and balance between these two?

    Yes, never connect it that way, you could do some serious damage to your gear.
    You could use the XLR main outs or the monitor out to your powered speaker. Just not the Kemper powered "speaker" output. Find yourself a passive speaker or guitar cabinet for that.


    You can run stereo by using the main outputs L/R, make sure the output for then is in stereo. You will be going into two powered cabinets, adjust then to the same output volume so the sound is even. Using the Kemper looper or any looper is good for a sound source while you balance the speakers output. Then everything is set inside the Kemper.

    Edited 3 times, last by drog ().

    Yes, I know now about the possible damage. I should have used the XLR main outs for FOH (its usual purpose) with these powered cabs.


    But if want to play in stereo on stage with 2 mono cabinets and my Powerhead? First I thought this only would be possible with an unpowered 19" version of the Kemper connected to a stereo powered amp. What about that monitor out + direct out for this matter?

    you can do that as long as you do not connect active speakers to the poweramp out


    all other KPA outputs are not powered, and thus you need powered speakers. and you can choose any KPA output among the mains L&R, the monitor and the direct out. just make sure that in the output menu you assign master L to one and master R to another.

    Not that long ago I was at an Open Door Day at one of the biggest music stores in The Netherlands. Of course there was a big demo of Kemper https://www.youtube.com/watch?v=9goc1R7AzBo

    The guy told me about his specific choice NOT to go for a powerhead but for a 19" version powered by a stereo all valve power amp, just for its stereo options on stage as well as for FOH! You see two 1x12 60W cabs behind him and above that his 19" Kemper and left from that his stereo amp, a Koch atr 4502.
    He connected his left and right speaker outputs to the l+r speaker inputs of the power amp and from there the l+r outputs to two QSC K 12 powered PA speakers, left and right from him in the video. A truly amazing sound...!


    Since the Powerhead has no two l+r speaker outputs, I assumed that it was not possible to play stereo on stage. I can recall a statement about this issue from someone in a topic in this forum who confirmed that. But now I read it surely is possible! Going to FOH after that is no problem with two Shure SM 57 mikes, right?

    Now I am confused..
    Do you mean you do need to connect 2 active speakers to the direct out en monitor out? So 2 mono 1x12 cabs won't do with the 600 w poweramp of the Kemper?


    And what if I use an extra valve amp for these outputs? Is that overkill because of the 600 w power amp or do I benefit from this?

    Yes that is correct that you will need two powered speakers to run the direct out and monitor out as stereo mix. You should also link those outputs to the volume knob and un-link the main outs that go to the FOH. This way you can turn up/down the volume for your monitors onstage without affecting the main mix signal.

    Neither the PowerHead nor the PowerRack will provide signal in stereo for passive cabs.


    From any Kemper Profiler, you need either a pair of mono amps or a stereo amp to use two passive cabinets in stereo. Any will also work in stereo with two active monitors.


    From any Kemper Profiler, you can use both the XLRs and the 1/4" outs at the same time. Therefore, you can feed the FOH and your own amps/active cabs if you desire without the need to use the direct out/monitor out.

    the player, there's only 1 power output on the powered KPA (mono). It is the red one. this is only on the powered KPA
    all other outputs are unpowered. this is on any KPA.


    as a conclusion, you cannot use the power output stereo but you can use 2 unpowered outputs stereo from any KPA.

    Pamplemousse: Thanks for your reply. I know now what to do if I want to have stereo on stage. Looking back I know why a lot of people have chosen for a 19" model. It's cheaper, comes with a deal for the remote (which I have to buy separately), can be rackmounted, and has an easier setup with a stereo power amp.


    I tried this stereo option on my powerhead with direct out and monitor out with two mono powered FRFR cabs and this gives a lot of sound spreading.


    Buty it's a bit hard to tell which settings in Output (Output sources) are best for real stereo, because they seem to sound alike:
    page 1: Monitor Output (Mod left) Direct Output (Mod right) OR
    Monitor Output (Mod mono) Direct Output (Mod mono) OR
    Monitor Output (Master mono) Direct Output (Master mono) OR
    Monitor Output (Master left) Direct Output (Master right) OR


    Any comment on this?


    Reading carefully the Reference manual (4.0) page 39 it now seems that I only THINK I'm listening to stereo because of my two powered speakers , connected to MONITOR OUT and DIRECT out. (BTW: I've set output volumes for these outputs to 0.0. dB on page 2 of the profiler). Several routings show not being available for DIRECT OUTPUT and MONITOR OUTPUT .
    example: Mod Left: Delivers only one side of the stereo signal of “Mod Stereo”. Where's the other side?
    example: Master Left: Delivers only one side of the stereo signal of “Master Stereo”.


    I'm really beginning to think that the powerhead, connected to 2 powered cabs, to DIRECT OUT and MONITOR OUT can't deliver a true stereo sound. Somehow it seems logical to me since it's about a one internal power amp of the Powerhead which delivers 600 W at 8 ohms (on page 33 of the Reference manual). Above this section it also talks about the "power of the built in class D amp".
    So it only could be the fx coming out in stereo through Monitor Out and Direct Out, sent to 2 powered speakers. But I can't determine that and the descrpions here above ("not available for....") seem to confirm that...
    Or I understand everything wrong...

    You are starting to confuse yourself. Do this from the manual...


    " You can also setup an individually controllable stereo output separately from the MAIN OUTPUT: set Monitor Output source to “Master Left” and Direct Output source to “Master Right”. Link both volumes of DIRECT and MONITOR OUTPUT to the MASTER VOLUME knob, and unlink Main Volume. Now you have a stereo monitor signal, controllable by the MASTER VOLUME knob, independent from the MAIN OUTPUT, which goes to the main mixing desk. "

    Quote from theplayer

    Looking back I know why a lot of people have chosen for a 19" model. It's cheaper, comes with a deal for the remote (which I have to buy separately), can be rackmounted, and has an easier setup with a stereo power amp


    The rack model is not cheaper than the head, doesn't come with a deal for the Remote (you can buy bundles with heads as well) and is just as easy to set up with a stereo poweramp as the head.

    The problem with the stereo output to two guitar cabs is that it's currently impossible to exclude the cab profile from Direct out. If you use linear cabs the problem does not arise.


    PS: FIY, the internal power amp is fed by Monitor Out.
    One of the consequences of this wiring would be that, if you had the same amp to be fed by Direct out, you'd have a perfectly balanced stereo signal.


    Just to give you a vision :)

    Thanks viabcroce. Clear explanation....if I knew what linear cabs are. So I looked it up and what I know now is that guitar speakers are non linear.
    In http://www.kpa-solutions.com/frfr-cabinets/ I read that FRFR speakers would be better.


    I haven't really a good guitar speakercab and surely not a powered one. What I do have are two powered FRFR speakers: http://www.qsc.com/live-sound/…rs/k-series/live-soundk8/but I can't determine if they are linear..


    Back to your reply: If they are linear, would I have then perfect stereo using Direct Out and Monitor Out?

    OK. That's clear. Thanks . But man, it's hard to accomplish...!


    I have made a rig called like Run to hell (yes, that one) using the stereo delay from the X section. I use a pretty clean amp like the 63 Vibroverb. I connected those two FRFR cabs to Monitor out and Direct out.


    The left speaker sounds very distorted with some delay in the background, the other one sounds clean and clear. There's also a very big volume difference between the two cabs. Still both are set to the same volume level. Within the profiler both volumes of Monitor out and Direct out are set to -20 dB. Both clean sense and distortion sense are set to 0.0. dB.
    But any balance is nowhere to be found. What do I overlook here?