Profiling adding extra sub bass not present on ref amp.

  • I’m getting tons of sub bass that isn’t in the original amp (5150 III) before and after refining. Not using any pedals in front, just the straight amp into a Suhr Reactive Load IR. I have to use an EQ to high pass everything up to 120hz or above to even get it in the ball park, then it has no balls. Did a recent update change accuracy? I listen to profiles i made before that didn’t have any problems like this. (I’ve owned it since 2015, profiled many amps and Yes, I factory reset all the settings etc etc). There is definitely something going on, I’ve seen many reports on other forums of extra sub bass being added. I thought maybe it was a problem for the Kemper using the reactive load box/IR so I miced up the amp and the same thing. I’ve profiled this amp before so they definitely changed something in the low end accuracy with the profiling process. I saw CK mentioned it doesn’t matter because it gets filtered anyway in a mix...well I don’t want Kemper making mixing choices for me, High passing a guitar that drastically to cut out the extra subs (a lot extra) causes phase issues and nueters the sound. What’s going on here??

    I have a treated room and top of the line Adam A77x monitors, it’s not my monitoring or my set up. Running analog out into a Lynx Hilo convertor. It’s not “mic placement” because it happens on both the IR and the mic’ed version, plus even if it was, the extra sub bass would show up on the reference amp as well.

  • I haven't heard of the Kemper adding sub-bass, quite the opposite - the low end seems to have less girth than the original amplifiers.

    I wouldn't low pass to 120hz while creating a profile, that would definitely result in the profile sounding less like a real guitar. So your results are not unexpected.

    Have you tried listening with headphones? I know your room is treated, but it could be that there are still nodes that make you perceive additional low frequencies when there aren't any.

    Also, could you post some clips of the original amplifier sound and the profiles?

  • The profiled amp has more subs than the real amp, you can hear it on all systems, including headphones. My concern is because of the complaints of lack of subs they jacked them up in an update. I remember years ago they removed the option for bass boost. Is there something that changed that makes a 5150 III EL34 harder to profile than before? ckemper ?

    The only way I can even reduce them is during the refining phase to place a physical EQ between the amp and the Kemper and cut out everything with a 12db high pass filter above 120hz . Something is going on, I’m very familiar with the Kemper (owned since 2015) and profiled many many amps over the years. As you said, before my only issue was lack of bass, now it’s overboard in the subs.

  • Same problem here ...... profiling is often pain in the ass . I have to cut low frequencies during the profile process . Most time the palm mutes are somewhat shifted an overpowered in the 100-120 hz department-refining adds more of this sub bass no matter what i do ! If you cut in this range . palm mutes sound better but the profiles sound thin and cold . It happens on all of my 7 Amps.

    I did watch Guidos profile videos -- so what is he doing better ???

  • Using a reactive load, maybe you are pushing the power amp (too much)? As we know, Kemper is not able to capture pre + power amp distortion (at the same time) correctly.

    That was my immediate reaction too but then the OP confirmed that they have also tested with a mic on the cabinet and get the same results so the loadbox doesn’t look like the culprit. I’m a bit baffled by it so am just following the discussion to learn something.

  • That was my immediate reaction too but then the OP confirmed that they have also tested with a mic on the cabinet and get the same results so the loadbox doesn’t look like the culprit. I’m a bit baffled by it so am just following the discussion to learn something.

    The main culprit is not the loadbox, but power amp distortion (and maybe amp settings).

    Maybe on the miked (no mice in the studio hopefully;)) version the power amp settings and bass were still too high (for the profiler to capture correctly)?

    Can we see a picture of the amp settings? What happens, when power amp is not pushed and eq is dialed in neutral?

  • I did watch Guidos profile videos -- so what is he doing better ???

    -He doesn't do the miking / profiling himself and let a pro engineer do the job;)

    - He sits in a high-end studio, using nice preamp and gear

    And still I have to reduce bass, use a Tubescreamer and something like Waves C4 (Andy Sneap setting) to get control over the low end with his profiles too.

  • What is this bug about? A bug only affecting profiling process and the result is a incorrect profile? Or can any rig be affected and have enhancend bass? When was it fixed and does the profile sound right again or does it stay "affected"?

  • Sorry guys, I’m away till tomorrow, I will provide screen shots of eq matching curves as well as sound samples. It’s consistent every time I profile that there are more subs so it won’t be hard to replicate. As for pushing my load box, I was only on 4 - 4.5 (around like 10:30 on a clock) on the master volume as I found that’s the sweetspot for the sound I’m going for on my 50watt EVH.

  • Which OS are you using?
    It wasn't exactly a recent update, but some time ago a bug that enhanced the low end was found and fixed.

    I forget the exact number because I won’t be home until tomorrow but it’s the update right before the newest one (8.???) The latest one didn’t seem like it did anything for the Kemper rack unit. I can install that one if you think it might help.

  • Hi guys, back home and ran some tests, EQ matching. I'm on OS 8.2.2 DonPetersen .

    Some background on the test:

    1. EVH 5150 III EL34 head into matching 2x12 cab, mic'ed with SM57 in the standard position (Mic placed where the cap meets the cone, standard metal mic'ing). All Knobs at 12 o'clock minus the volume which was set to 10'oclock. Set the resonance on the back to 0, tried it with my "normal setting of about half way up and the subs were completely out of control, this was the only way i could even get the sound to not sound ridiculous.

    2. I used a looping pedal so that all the sound tests were the same material/riff.

    3. I recorded the original amp, then the profiled amped before and after refining. Also included versions where im bouncing back and forth so you can see the difference without changing files. The one that bounces back and forth starts with the Kemper profile, then to the original, and then back again.

    4. I EQ matched pre and post refining. as you can see anything below 100hz is out of wack. Also the high-end is completely diffrent but I mainly notice the sub bass.

    Link the files and screen shots:…dEhouF4FIVdTi3_hycqa?dl=0

  • Updated to the latest OS, same issue.

    I'd love to resolve this, been loyal to Kemper since I bought it in 2015, Profiled a ton of amps back then (which profiles I still use to this day), Just started up profiling again and the low end accuracy is much different than before. Back then, as others have said, it might have been a little light in the low end, but that was much more useable than it is right now for me. As others have said, really noticeable in palm mutes, sounds like "And Justice For All" speaker woofing Even when its not supposed to haha.

  • Further updates, I tested the load box vs mic’ing and then EQ matched. The mic’ed version is worse than the load box version. It’s adding a ton of extra crap under 100hz.

    I then decided to profile my JCM800, to rule out that it’s just a problem capturing an EVH 5150 III. I didn’t use any pedals and low and behold, that one is also adding more subs than what’s present. Can someone look into this? I’m pretty much ready to sell this thing. It’s one thing if it was always like this, but My profiles from 2015 sound way better on my JCM 800 with the exact same gear.

    Someone told me that own both the stage and the toaster that this problem happens to them only with the toaster but doesn’t appear with the stage. ckemper ??

    I own the rack version.

  • Have you contacted support to clarify if this is the bug mentioned earlier?

    I know such things can be very frustrating!

    We can only guess and have no real solution.

    Have you checked if in the Output section "Pure Cabinet" is off and all EQ are set flat?

    I really hope you can figure out what is wrong