User Manual

KEMPER PROFILING AMPLIFIER20
 Tube Shape
“Tube Shape” controls the distortion characteristics of the tubes, ranging from very soft to very hard. All
kinds of crunch sounds can be dialed up, from warm blues to singing metallic to harsh. Depending on the
gain setting or the playing style, the resulting eect can be rather subtle; completely distorted sounds are
mostly unaected by this parameter, as are clean sounds. Set the value to 3 o’clock to simulate the typi-
cal sound of preamp tubes. To achieve a power amp tube character, try setting “Tube Shape” to 9 o’clock.
Power amp tubes produce a much harder distortion, because the negative feedback in the power amp cir-
cuit linearizes the tube amplification, making the distortion curve edgier.
 Tube Bias
“Tube Bias” influences the overtone structure of the distortion. While the eect on the character of the
sound is fairly subtle, you should feel a quite a dierence in the distortion dynamics: as you increase the
amount of “Tube Bias” the guitar will go into distortion much earlier in the dynamic range, yet still retain a
lot of dynamic headroom. At maximum value the distortion characteristics mimic those of a Tube Scream-
er.
EQ
Holding the EQ button will bring the equalizer into focus. Use the soft knobs to control the frequency
bands of the equalizer. We assume that you will have set the equalizer of the reference amp to your pre-
ferred setting before profiling. Eectively, the equalizer in the KPA is a recreation of a generic passive
tonestack, but it is designed to have more impact on the frequency bands. When all soft knobs are in the
middle position, you will hear the unaltered sound of the profile.
Cabinet
The CABINET button brings the cabinet section into focus. You can freely combine cabinets and amps
from dierent profiles to create new stacks. The cabinet has three parameters to tweak its character in an
artificial way: