Impulse responses sound different after imported into profiler

  • I’m trying to use direct profiles with my own impulse responses. I can play through the direct profile with the cab section turned off, with the profiler’s main output plugged into my computer, which has the IR loaded into a plug-in (RedWirez MixIR3), and it sounds great. But if I remove the plug-in from the equation and import the IR into Rig Manager and load it into the profiler, it sounds like there’s a significant bass frequency roll-off. It sounds completely different loaded into the Profiler than it does running in MixIR3.

    Can anyone tell me what’s going on? Is this normal? Is there some setting on the profiler that needs changing in order for impulse responses to sound correct?

  • Didn’t try that but maybe it’s gain related.

    Not the gain of the amp section but the gain/level with the daw/soundcard you are sending to MixIr3.

    As the kemper is not a soundcard like a fractal for example you need to be really careful and spend a lot of time with those input/output level

    but I may be wrong though.

    Also check if there’s no eq activated in MixIr

  • I don’t think it’s a gain issue. The profiler is connected to my interface via S/PDIF and this removes output levels from the equation. It’s also not specific to MixIR, as I get the same results if I load the IR into Space Designer. I can increase input levels and reduce output levels, and vice-versa, but the result is the same. The Kemper is definitely shaving bass off the impulse response.

  • I haven't noticed the same issue, though I suppose I've not listened that closely after bringing IRs into the Kemper. I tend to just drag them en masse and assign them as needed.

    There is a conversion that goes on when importing IRs, maybe that affects the sound?

  • I believe the IRs are truncated (shortened) significantly when imported into the Profiler. This could theoretically cause the bass roll off that you’re experiencing, if there is no compensation during the conversion.

  • Don't think the Kemper uses any IR tech internally for the cab. I mean the original rig files were like 3-6 kb in total? Not a lot of data there. Instead it could be converting the IR into an approximated frequency curve or something.

    Would be interesting to hear a recording of both situations to compare.

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