I just isn't happening on my unit at all. No aliasing.
That's amazing--consider yourself lucky--are you positive that you are listening for precisely the issue as demonstrated in post #1 of this thread? It would be awesome if you could provide a sound clip.
i wonder if this has something to do with input level... ck mentioned the unit has a ton of headroom, maybe this only happens with hot pickups plus tons of gain. i will try messing with clean sense and different guitars as input. so far i mainly used a strat with emgs and active tone controls and an asat with charlie christians (pretty hot pickups), hmmm all single coils too...
Nope! No one is talking about a major disappointment, but as others complain about the editor/handling of rigs, we do the same about these problems. So what?
Again I mean no disrespect, just trying to understand. In a previous post you claim to have had a ZZ Top idea which wasn't possible to realize with the Kemper due to this issue. I can not afford an ~$2,000 USD device which will limit my creativity. We are not talking about a functional defect here, but a tonal one. I'm not even specifically arguing as to whether or not the phenomena exists, only that if it is an issue such that it limits your playing...why stick with the device? Is this a case that despite the issue you feel the Kemper is still one of the best choices on the market?
hehe almost 2 decades of internet and it still amazes me how dismissive folks become when they don't understand something...
That's awesome. You've exhibited the very behavior you're lampooning in the same post. 
In my case, this is something that I did not know when I bought the unit on its release. Since Kemper have been improving and fixing other things, you would expect that this is one they will fix as well. So far we don't know if this will be fixed or not. I guess that most of us that notice it would like to know if they are going to take care of it or not before taking any decisions.
But shouldn't it have been obvious to you after auditioning the unit? I mean, if someone else has to point out that a problem exists, does the problem really exist for you? Again, not even arguing whether the issue does or doesn't exist but for $2K I would have packaged the unit up and set it back if it didn't work for me. Honestly, after the first hour or so of usage I was considering that until I found some user profiles I liked and got some of the commercial profiles. For whatever reason, I don't care for the majority of stock profiles.
That's amazing--consider yourself lucky--are you positive that you are listening for precisely the issue as demonstrated in post #1 of this thread? It would be awesome if you could provide a sound clip.
I'll try it get to it over the next few days or so, but I've got a some commitments which will take precedence. Does it have to be the same profile? I keep my unit lean and am not going to re-install all the factory stuff just for this...
the thing is its an issue that's not easily identified , I didn't hear it in the first couple weeks i had my kemper , i had to dig deep , and listening with headphones and then I wasn't sure if it was certain profiles or firmware or hardware etc.
Its most noticeable to me on really high notes with alot of gain when i first pick it and bend a little its like a ghost growling noise some alias frequency.
I think the kempers sound is awesome other than that wonder if this can be fixed by firmware , or if we will have to buy new hardware , imagine the kemper 2 faster processor etc , but yikes spend all that money again ..
just liek axe fx then they come out with axe 2 , etc
But shouldn't it have been obvious to you after auditioning the unit? I mean, if someone else has to point out that a problem exists, does the problem really exist for you? Again, not even arguing whether the issue does or doesn't exist but for $2K I would have packaged the unit up and set it back if it didn't work for me. Honestly, after the first hour or so of usage I was considering that until I found some user profiles I liked and got some of the commercial profiles. For whatever reason, I don't care for the majority of stock profiles.
Nobody had to tell us (or at least me) that the issue exists. Just because someone does not open a public thread about it or discuss about it publicly here, that does not mean that the issue was unnoticed. The decision about sending it back or not due to this or other issues is something entirely up to each individual. In my case this is the only issue I have with the KPA so far and it is not a deal breaker for me at least for now. Having owned most of other modellers including the Axe Fx II (which does not suffer from aliasing) the KPA is the one that works best for me for different reasons. I still hope that they can fix this issue and If they can't then at least let us know as well.
That's amazing--consider yourself lucky--are you positive that you are listening for precisely the issue as demonstrated in post #1 of this thread? It would be awesome if you could provide a sound clip.
I finally heard it in the first post clip. Had to crank my studio monitors way up.. not sure what to think
I finally heard it in the first post clip. Had to crank my studio monitors way up.. not sure what to think
Yeah, some people have to listen deeply at first to notice it, then once you know it's there, and proceed to linger in the upper register of your guitar with a high-gain profile, it compromises an otherwise stellar tone. Imagine what Eric Johnson would say. 
That's awesome. You've exhibited the very behavior you're lampooning in the same post.
not that i'm above lampooning myself, but i'm not seeing this, what don't i understand?
you seem to be asking questions like you are confused and yet offering advice anyway.
this love it or leave it attitude is helping no-one...
but enough derail...
meanwhile i was able to repeat this with 4 very different guitars.
- strat - dg-emg pickups
- asat - charlie christian pickups
- lucille - duncan jazz humbuckers, 13s
- godin lgxa - stock godin humbuckers
i used the kemper profile JMP77-001 (just the first kemper profile i found that behaved this way - turn off distortion and delay, crank the gain) and can consistently get the "suffocating alien" sound by playing high D (2nd string 15th fret) and bending up to Eb and slowly bending it slightly. with full feedback this even can result in the synthetic swoops we normally associate with aliasing. the pitch moves much further than i would expect, a microtonal bend can move it a lot, so maybe some other mechanism is at play...
i watched the input level and output level leds to avoid red.
i tried modding clean sense (no effect) distortion sense (also no effect) and presence (quite a bit of effect)
some presence boost brought the artifacts up front, though the character didn't change.
this is unsurprising, but might be useful for repeating the experiment.
i also was able to get the suffocating alien with the guitar volume turned down on all guitars, so i think the hot pickup idea is busted.
note that i didn't find this because someone else pointed it out, i was sometimes hearing these strange swoops in the opposite direction of bends and went to investigate. this is not the only way to get the effect, but hopefully at least is a repeatable way...
I finally heard it in the first post clip. Had to crank my studio monitors way up.. not sure what to think
Strange, you should not need to crank them up. The aliasing effect (howling sound) is pretty loud in that clip. I hear it even in my computer speakers at low volume.
uld not need to crank them up. The aliasing effect (howling sound) is pretty loud in that clip. I hear it even in my computer speakers at low v
It seems like its actually guitar fret noise.. it doesn't strike me as aliasing. Could be wrong. Its almost like the fret noise is harmonically effecting the primary note in places. I wonder if guitar speakers do this in real life. Feels like something that goes away with tube saturation/volume.
[edit] here is a spectral screen shot. in it you can clearly see extra frequency information superimposed over the primary frequency. guitar noise? fret noise? aliasing? do not know.
[Blocked Image: https://dl.dropbox.com/u/29745912/spectralview.png]
Miles
Can you demonstrate the aliasing in the context of a piece of recorded guitar music?
I notice all the clips on your Soundcloud page are one chord strumming "tests".
Miles
Can you demonstrate the aliasing in the context of a piece of recorded guitar music?
I notice all the clips on your Soundcloud page are one chord strumming "tests".
I have demonstrated that there is an issue, others have confirmed this including Kemper, I have invested more time into this than I ever wanted to, and though I am usually up for a worthwhile challenge, I don't see your request as one that I care to do. I have a busy production schedule as it is, besides there would be so many variables in choosing style, density of the mix, etc... thanks for asking though.
Good morning guys, hope you had a good night ......... 
Ok, I had my KPA for some hours or so when I first noticed the artifacts, and been some kind of surprised. (I did not expect that from the Kemper, and still think that this is a "no go" for such a piece of art) I checked out the forum and found this thread here, and so I thought:
"Ok, the guys know about that and will fix soon!"
That did not happen, and that´s the reason why I posted here in this thread, because this issue is a restricting one to me. The KPA is absolutely amazing, and I´m very satisfied with that lil radio, but the artifacts restrict me in my playing for sure.
PS.: Most of the time I´m playing very low volume via my Adam A5X speakers, and I can hear these at lowest volumes when they occur.
PSPS.: ZZ Top - When playing Billys very compressed guitar sounds (listen to Antenna) there is many of these pinch harmonics, and when using an artifact sensible setting on Kemper (depending on gain) you might get artifacts all the time. That happened to me and caused my postings finally.
PSPSPS.: I think that an official member of the Kemper crew should write some words here, but here it seems like no one wants to take a stance?
PSPSPS.: I think that an official member of the Kemper crew should write some words here, but here it seems like no one wants to take a stance?
Well that certainly would be a welcome addition to this thread.
In my opinion "no comment" equals to a possible bad news that might affect the sales...
I hope I'm wrong though. I can hear the aliasing on my unit when I look for it specifically, but during normal use, it does not bother me much. Definitely a shortcumming for a fully grown digital unit though that needs to be eliminated if possible.
In my opinion "no comment" equals to a possible bad news that might affect the sales...
I hope I'm wrong though. I can hear the aliasing on my unit when I look for it specifically, but during normal use, it does not bother me much. Definitely a shortcumming for a fully grown digital unit though that needs to be eliminated if possible.
Same for me as I do not play extremely high gain music generally. The more worrisome aspect of the issue though is the radio silence from the company.
Same for me as I do not play extremely high gain music generally. The more worrisome aspect of the issue though is the radio silence from the company.
I'm not 100% convinced that the company thought about future-proofing, or were expecting guiarists to be this demanding. Perhaps for them after 6 years the Kemper was an end product rather than the launch/beginning of a platform that it seems most of us users were expecting.
Based on the responses to some of the user requests I get the feeling that to them it's a completed thing, then again perhaps that's just down to how (and what) they're choosing to communicate on the forums and is an erroneous conclusion. It would certainly be nice to hear something conclusive in this thread.
I just realized looking at the amount of views this thread has, that this probably is the most read thread on this forum - or atleast right there on top. I personally don't have a problem with the artifacts discussed here (be it my ears, playing style or lack of it...), but there seems to be a lot of interest in this.
And on top of that you also have threads like the one below on other forums:
http://www.ultimatemetal.com/f…mper-profiling-amp-9.html
So I guess some comments from the KPA staff would be welcome. But I also know from the few contacts I've had with Kemper support that they are really forthcoming on the issues raised in email exchange even if they don't discuss or speculate on those issues in the same detail on the forum - until they've had a solution to offer. So I'll be happily playing my KPA and following this thread occasionally. But if this is causing sleepless nights for some users, it may be worth contacting support to see what they got to say about this. And hopefully some solutions will arise for those who already have done just that.
