Ok, as I promised, I did some tests on the AMP EQ of the Kemper to see how the filter works.
I did this test recording a "large" spectrum track with the guitar and than recording the same in loop with the Amp EQ at different settings.
As always "trust your ears" is the better valid solution, but I believe that this additional information can be very useful to know, when you have to tweak. The 4 filters Bass, Meedle, Treble and Presence are all sufficiently large as bandwith, so they are perfect, for my point of view, for a first equalization of the output signal after the amp section. If one wants a more narrowed and dedicated filter must use the Studio EQ or the Graphic one.
The graphs are self-explanatory, I just added few notes.
Bass EQ (range -5 +5 going more or less from -12 to +4 dB at 80 Hz). It is a shelving filter that start works under 800 Hz, and progressively grow until 0 like in the figure, the mid line is with EQ Bass Flat at “0”, the others snapshot are taken at Bass equal to -5 and +5.
[Blocked Image: https://dl.dropboxusercontent.com/u/56839802/_EF…20vs%20Flat.JPG]
Middle EQ (range -5 +5 corresponding from to -7 to +5 dB). It is a band pass filter on the center frequency like in the figure below. The center Freq seems around 600-800 Hz, it has a very large bandwidth. The mid line is with EQ Flat at “0”, the others snapshot are taken at Middle equal to -5 and +5.
[Blocked Image: https://dl.dropboxusercontent.com/u/56839802/_EF…20vs%20Flat.JPG]
Treble EQ (range -5 +5 going more or less from -12 to +4 dB over 10.000 Hz). It is a shelving filter that start works above 500 Hz, and progressively grow until 20.000 like in the figure, the mid line is with EQ Flat at “0”, the others snapshot are taken at Treble equal to -5 and +5.
[Blocked Image: https://dl.dropboxusercontent.com/u/56839802/_EF…20vs%20Flat.JPG]
Presence EQ (range -5 +5 equal to -12 +12 dB)
It is a shelving filter that raise or lower from -12 to +12 dB like in the figure below. It start works above 500 Hz, and progressively grow until 20.000 like in the figure, the mid line is with EQ Flat at “0”, the others snapshot are taken at Presence equal to -5 and +5.
[Blocked Image: https://dl.dropboxusercontent.com/u/56839802/_EF…20vs%20Flat.JPG]
Hope it can help
P.S.
Here you have the Main Output EQ behaviour:
MAIN OUTPUT EQ