Lost low frequencies...?

  • Hi everyone,


    First of all, sorry for my English I'll try to do my best to be clear.


    I have a problem with every bass profiles, I lost a lot of low frequencies in comparison of my bass dry signal. I just made two examples with two different profils, it will be more explicit than words.


    Here is an example with an SWR 350 rig, listen it with headphone will be better than a computer :


    SWR 350 :


    Dry signal :


    And here the screenshot of the frequencies response, on the top the SWR rig, you can see clearly the lost of low end :


    [Blocked Image: http://i67.tinypic.com/2zez9kh.png]
    Now with an Ampeg SVT 1978 :


    And dry signal :


    The screenshot :


    [Blocked Image: http://i68.tinypic.com/3338x79.png]


    Even if I put an EQ, I lost the low end, the sound is not rich and full as the dry signal. So my question is, do you have some tips/tricks to don't loose that ?


    Thanks guys to helping a newbie Kemper user :D

  • Use the parallel path and maybe Low-pass filter the direct sound, so you're only getting the lows that you're missing from the dry signal.

    Seems to be excellent advice.


    On the other hand I'd like to understand the technical reason why this happens. Is this how profiles work? Maybe when they have been created with guitar instead of bass?

  • I have the same problems even on the DI profiles, so the question is, is the Kemper has a lack of low frequencies response ? It was built for guitarist, I'm a guitarist too and nothing to say about that, it's an awesome box, but for the bass I'm confused, so I wanted to do that thread to share my impression and see if I'm alone with that feeling and cash some tricks, because I'm not an expert with the Kemper, there is so much things to do.

    Use the parallel path and maybe Low-pass filter the direct sound, so you're only getting the lows that you're missing from the dry signal.

    Thanks for the tips, I already tried to use the parallel path, but the signal from the dry signal is very low, and if I turning down the volume of the rig, the dry going down as well, is there something to equilibrate both signals ?

  • I have the same problems even on the DI profiles, so the question is, is the Kemper has a lack of low frequencies response ? It was built for guitarist, I'm a guitarist too and nothing to say about that, it's an awesome box, but for the bass I'm confused, so I wanted to do that thread to share my impression and see if I'm alone with that feeling and cash some tricks, because I'm not an expert with the Kemper, there is so much things to do.

    Thanks for the tips, I already tried to use the parallel path, but the signal from the dry signal is very low, and if I turning down the volume of the rig, the dry going down as well, is there something to equilibrate both signals ?

    If you put an EQ Stomp in one the two slots that are assigned to the Parallel Path, you can turn up the volume there (though you might need to use a compressor too, to tame any peaks, so if you don't need the low-pass filter, the compressor on its own is fine).

  • I think it depends how the low freq. are captured or the emulated amp can handle low freqencies.


    I tried the following:
    https://monosnap.com/file/8UqU2r1JK2E2egipgaYR8yhgcHJ8P7#


    So if stack sectioin is off I can see no difference between the DI and KPA freq. response.
    The kpa profile i used is from guido and I think it acts like a real miked amp.
    So if somebody need more low freq. for recording then you can blend both together (or take on individual tracks the freq. band you want).

  • You will always get these results when comparing a DI signal with one that went through an amp/cab/mic.
    As already pointed out, use the parallel path feature or the Direct Mix parameter to add DI to your amp sound. The ratio between parallel and amp signal is controlled by the parameter on the same screen as the Parallel Path tick box.


    hth

  • As I already said, I have exactly the same problem with DI amps profiles, so it's not a problem from the take with cab/mic. I tried to configure a good sound with parallel path, but it's very difficult to have a good middle point, when the low end coming thru the dry signal is too much on the front, and there is so much things to do with an EQ, low-path filter, compressor in both side that I lost my brain yesterday 8o

    This is the Kemper's frequency response with absolutely nothing turned on:


    [Blocked Image: https://dl.dropboxusercontent.com/u/7231524/Reference.png]


    There's a ~6db roll-off below 50Hz or so, but anything more than that is coming from the Amp or Cab section.

    Thank you very much for that, 50hz it's very high, bass signal going more lower and I used only 5 strings basses.

  • As I already said, I have exactly the same problem with DI amps profiles, so it's not a problem from the take with cab/mic.

    I think what he means is that the Kemper is designed to emulate an amp, cab and mic chain. Therefore, the low end roll off is intentional (or perhaps deemed negligible, if it's a side-effect of the Profiler's architecture), as this mirrors the real world.

  • As I already said, I have exactly the same problem with DI amps profiles, so it's not a problem from the take with cab/mic. I tried to configure a good sound with parallel path, but it's very difficult to have a good middle point, when the low end coming thru the dry signal is too much on the front, and there is so much things to do with an EQ, low-path filter, compressor in both side that I lost my brain yesterday 8o

    Thank you very much for that, 50hz it's very high, bass signal going more lower and I used only 5 strings basses.

    To me it looks like the signal is down -2dB at around 40 Hz and maybe -4dB at 30 Hz, from where it drops off more steeply.

  • I think what he means is that the Kemper is designed to emulate an amp, cab and mic chain. Therefore, the low end roll off is intentional (or perhaps deemed negligible, if it's a side-effect of the Profiler's architecture), as this mirrors the real world.


    I could also imagine that a lot of roll-off happens in the lower frequencies inside the amp itself. That's at least a big part of guitar amps, rolling off the lows so everything doesn't mud up

  • Thank you very much for that, 50hz it's very high, bass signal going more lower and I used only 5 strings basses.


    - For what it's worth the AKG D112 and Neumann FET 47 - two well-known bass cab mics - have pretty much the same roll-off. See here and here. Odds are very good that any albums you like with a lot of sub bass were recorded with a DI.


    - It's such a gentle roll-off that, as @Michael_dk said, you aren't really losing any content until around 35Hz. Incidentally, that's roughly your low B string.


    - Have you ever looked at the frequency response of your bass in an analyzer? In my experience the second harmonic (so ~70Hz for you) is where all the beef lives. Sub bass extension is awesome, sure, but it's just helping out.


    - Don't forget that the amp profile includes its own EQ response too, separate from the cab. Have a look at the thread in my signature; there's a PDF there with lots of handy pictures. Specifically, take a look at the Amplifier section on p18 - the red image on the right-hand side is as close to "flat" as that particular profile gets.