Unable To Turn off cabs??

    I think I may have posted this in the wrong place initially...


    Howdy... I'm right in the middle of profiling my Mesa Formula Preamp and I'm running into an issue trying to get a clean direct sound.


    I have the guitar plugged into the kemper front panel input, and the Formula's direct out (non cabinet sim output) going back into the Kemper's return input. When I attempt to make a clean profile with cabinets turned off, the resulting profile always seems to have the high frequencies rolled off, like the kemper is forcing a cabinet on. When I compare the reference amp to the kemper profile, the reference amp has the bright direct sound as if the preamp was plugged directly into my console but the kemper profiles sounds as if the high freq's are being rolled off. Doesn't sound anything like the reference amp.


    Any suggestions? It sounds like there is always a cabinet sim even when switched off. I just can't seem to get that same bright direct sound I get from the reference amp. Maybe the KPA can't do a direct non-cab preamp direct sound?

    glennfinn,


    could you specify the whole signal chain please? Do you disable the cab section while monitoring thet new profile? Or are you using monitor out with Monitor Cab Off activated?

    Hi Hell-G.....


    Guitar to kemper front panel input, Kemper direct output send to Formula preamp input, Formula preamp output to Kemper return input, kemper main outs to mixing console input, listening on powered studio monitors connected to console output. I assume this is the correct (only) way to profile a preamp. :?:


    I did some more experimenting and what i discovered was that the Kemper seems to be adding some sort of pre-emphasis to the signal coming into the return input. During the profiling process, when listening to the "reference amp" it sounds like it's got some sort of HF EQ boost added to it.


    What I did to confirm this was to compare the sound of Formula preamp directly connected to the console, (no kemper, just guitar to preamp to console) to the Formula connected to the kemper listening to the reference amp sound during profiling. They are different! The kemper is adding something that's not there with just the guitar - preamp - console. Shouldn't the reference amp sound the same as the reference amp not going through the Kemper?? It's a mystery!


    ?(

    Quote from HELL-G

    glennfinn,


    could you specify the whole signal chain please? Do you disable the cab section while monitoring thet new profile? Or are you using monitor out with Monitor Cab Off activated?


    Sorry... didn't answer your question.... Yes, the cab section is disabled and I'm listening to the main outs, not the "monitor output"