Kemper vs. Real Amp Test - Cameron CCV

  • Do all TS808/TS9s and their clones sound identical, do all JCM800s sound identical when recorded, how about identical cabinets with the same speakers, do they all sound identical when mic'd and recorded?


    So what's the point of this discussion?

    This has been the substance of most of my comments on the subject.


    I would gander a guess that most of us here have a rich history of high end tube amps. Anyone with that history who says that the tone of their tube amp rigs did not have consistency issues over time, re-tubing, temperature, time after startup, mic placement, etc, etc, is simply incorrect (or just has a amorous version of those memories).


    There are differences. Dead stop. No one here is saying that there are not.


    The differences are quite minuscule though, and the Kemper is dead-nuts-on exactly the same tone gig after gig after gig. That was never the case for my tube amps. YMMV.

  • Speaking of Kemper's EQ response, my limited experience is that Kemper quite ofter produces a bump above 100Hz and a dip from 90Hz downwards. That may be the reason Kemper sometimes sounds more "boxy" or "congested" or "smaller" than the original source. There are other differences too, but this phenomena is the most consistent in my, again limited, experience. Something like in this picture:

    This is exactly what I reported to support when I tried to DI profile my bass amps.


    And those frequencies are very important for the bass.

  • There is obviously some filtering trickery going on around the guitar input of the KPA. CK mentioned back around 2012 that he is working on tweaking the high-pass filtering of the inputs in order to reduce relatively bad digital artifacts/aliasing of the early firmwares. These artifacts had been reduced during the years, but it is highly likely that the workaround filtering tricks resulted in a slight bass response mismatch between the profiles and the source material. Remember the low frequency correction switch that was introduced a few years back? This is now gone and ON by default. I think it tries to correct the cut low-end of the profiles. Maybe this correction method can be revised a little bit further in order to get better bass response? Or maybe a new KPA is on the horizon with better A/D D/A converters that require less filtering tricks? Only CK knows. In the meantime the base line is that while the KPA might sound a little different from certain profiled amps, it is still a really good tool and above the rest of the competition.

  • There is obviously some filtering trickery going on around the guitar input of the KPA. CK mentioned back around 2012 that he is working on tweaking the high-pass filtering of the inputs in order to reduce relatively bad digital artifacts/aliasing of the early firmwares. These artifacts had been reduced during the years, but it is highly likely that the workaround filtering tricks resulted in a slight bass response mismatch between the profiles and the source material. Remember the low frequency correction switch that was introduced a few years back? This is now gone and ON by default. I think it tries to correct the cut low-end of the profiles. Maybe this correction method can be revised a little bit further in order to get better bass response? Or maybe a new KPA is on the horizon with better A/D D/A converters that require less filtering tricks? Only CK knows. In the meantime the base line is that while the KPA might sound a little different from certain profiled amps, it is still a really good tool and above the rest of the competition.

    What is interesting to me is that aliasing issues occur at the high frequencies. Low frequencies are quite easy to get exactly right when doing time domain to frequency domain translations. There may well be something here that I don't have a complete understanding of (obviously). If it were easy, the bottom end would be perfect already ;)

  • That "gating" effect is not only present in palm muting passages. I can hear it in some parts in the following test. The KPA is not as clean (couldn't find a better word) as the profiled amp. It is present when the picking is harder. Both versions were recorded at the same time. The direct output of the KPA into the amp. Is the difference small?


    Moderator Notice:

    In most cases, Soundcloud uses a bandwidth of only 128 kbps. As a result, what you hear isn't free of artefacts, especially the high end. For critical listening and also product comparison, please keep that in mind. Users who setup a comparison should use linear wave files and supply dropbox links.

  • And now a different amp (JTM). In this case, there is a difference in the lows, but I think that the difference is small. I can't hear other significant differences.


    Moderator Notice:

    In most cases, Soundcloud uses a bandwidth of only 128 kbps. As a result, what you hear isn't free of artefacts, especially the high end. For critical listening and also product comparison, please keep that in mind. Users who setup a comparison should use linear wave files and supply dropbox links.

  • That "gating" effect is not only present in palm muting passages. I can hear it in some parts in the following test. The KPA is not as clean (couldn't find a better word) as the profiled amp. It is present when the picking is harder. Both versions were recorded at the same time. The direct output of the KPA into the amp. Is the difference small?


    Moderator Notice:

    In most cases, Soundcloud uses a bandwidth of only 128 kbps. As a result, what you hear isn't free of artefacts, especially the high end. For critical listening and also product comparison, please keep that in mind. Users who setup a comparison should use linear wave files and supply dropbox links.



    And now a different amp (JTM). In this case, there is a difference in the lows, but I think that the difference is small. I can't hear other significant differences.


    Moderator Notice:

    In most cases, Soundcloud uses a bandwidth of only 128 kbps. As a result, what you hear isn't free of artefacts, especially the high end. For critical listening and also product comparison, please keep that in mind. Users who setup a comparison should use linear wave files and supply dropbox links.





    My goodness...if there is a difference, it is no more of a difference (IMHO) than between two of the very same model valve amps, made during the same production run, on the same week.


    Cheers,
    John

  • That "gating" effect is not only present in palm muting passages. I can hear it in some parts in the following test. The KPA is not as clean (couldn't find a better word) as the profiled amp. It is present when the picking is harder. Both versions were recorded at the same time. The direct output of the KPA into the amp. Is the difference small?


    Moderator Notice:

    In most cases, Soundcloud uses a bandwidth of only 128 kbps. As a result, what you hear isn't free of artefacts, especially the high end. For critical listening and also product comparison, please keep that in mind. Users who setup a comparison should use linear wave files and supply dropbox links.


    This one sounds like you may need to adjust the input sensitivity settings on the Kemper. The first one is breaking up slightly ahead of the second and the volume is slightly lower on the second which makes me think the input signal strength isn't a match, not because the reamp is incorrect, but because the input sensitivity value on the Kemper is attenuating/boosting the signal before processing.


    Otherwise honestly, I can barely hear a difference.

  • This one sounds like you may need to adjust the input sensitivity settings on the Kemper. The first one is breaking up slightly ahead of the second and the volume is slightly lower on the second which makes me think the input signal strength isn't a match, not because the reamp is incorrect, but because the input sensitivity value on the Kemper is attenuating/boosting the signal before processing.
    Otherwise honestly, I can barely hear a difference.

    I don't think it's a sensitivity problem. In my opinion, the KPA doesn't match the dynamics of the amp. The first part is ok because I was playing softly but every time I pick hard the KPA doesn't match the profiled amp.

  • My goodness...if there is a difference, it is no more of a difference (IMHO) than between two of the very same model valve amps, made during the same production run, on the same week.


    Cheers,
    John

    I agree on the second clip, the JTM. On the first one, the Dumble clone, the dynamics are very different when picking harder and I don't like the way it sounds.

  • I don't think it's a sensitivity problem. In my opinion, the KPA doesn't match the dynamics of the amp. The first part is ok because I was playing softly but every time I pick hard the KPA doesn't match the profiled amp.

    Did you actually try lowering your Distortion Sens parameter on the Kemper?

  • Hey guys, I have been working with Mark Cameron himself to nail the tone of his amps on the Kemper, after 6 months of trial and error we both feel that we nailed down the tone and feel of his amps. I can't say what but there was a trick and a way Mark does it but judge the clip for yourselves and decide:


    *removed*



    Real amp:


    Code
    1. <iframe width="560" height="315" src="https://www.youtube.com/embed/YKGCkmVzLoo?rel=0" frameborder="0" allowfullscreen></iframe>
  • EDIT to add I got it to work!!!lol


    I'm still having a hard time getting the second clip to embed for some reason if someone wants to do it for me this is the direct link:


    *removed*



    I'm new here so still trying to figure out the forum posting software but thanks for the welcome MM!

  • Hey, no worries bro'.


    Just pasting the link works, man, so you've already done it now. Wuddun, mate!


    No need to futz around with source code. Hitting the top-left "square" button in the posting window to show the source code is handy for renaming links without affecting the url data, but apart from that, you could pretty much ignore it.

  • Hi!


    Thank you for posting those clips. The real amp clip sounds much better than the KPA to me. They are very different.


    How could one possibly tell? A true A/B comparison wasn't performed. The KPA was mic'd and recorded through the Marshall cabinet, whereas the reference Cameron mod'd Marshall was mic'd and recorded separately, apparently at a completely different point in time. Just look at the upload dates of the YouTube clips.


    Also, with all respect and cordiality, @SuckerFreeGear, you should post your KPA profile advertisement in the appropriate forum subsection, i.e. "Commercial Rigs and Profiles".


    Cheers,
    John

  • How could one possibly tell? A true A/B comparison wasn't performed. The KPA was mic'd and recorded through the Marshall cabinet, whereas the reference Cameron mod'd Marshall was mic'd and recorded separately, apparently at a completely different point in time. Just look at the upload dates of the YouTube clips.

    he said "judge for yourselves"... the second clip sounds much better.

  • he said "judge for yourselves"... the second clip sounds much better.


    I guess my point is this...
    All one can say and judge by those two clips is that one recorded clip sounded better than the other. The problem is, the subjective, personal preference cannot be fine tuned any better than this rather general statement. Since these were two separate recordings, apparently made at two separate times, ANY NUMBER of factors could be involved which affect the results.


    However, if this had been done in a single take, single recording of a properly set up KPA vs Reference tube amp A/B comparison recording, in which the KPA profile and the Reference amp are flipped back and forth...one could at least identify for certain that, all else being equal, one preferred the reference amp tone to the KPA, or vice versa.