User Manual

KEMPER PROFILING AMPLIFIER18

 Power Sagging

“Power Sagging” models the interaction between the guitar signal and the distortion stage. Increase the

amount of power sagging to emphasize the velocity and energy of crunch sounds. The guitar sound gains

additional energy and presence, without raising the perceived volume of the distorted signal. When you

turn “Power Sagging” beyond 50%, you go beyond what can be achieved with an analog tube amp, but

without losing any of the natural characteristics of the sound. At full force, power sagging can make spar-

kling clean notes sound louder than distorted ones, so you can use it to expand the dynamic range of the

original sound. With “Power Sagging” set to 0%, the original dynamic range of the proﬁle is maintained.

Power sagging is a phenomenon that occurs when the tubes draw a lot of electric power at high distor-

tion rates, thereby weakening the supply voltage. Under such load, the tubes will change their distortion

characteristics and sort of shut down; then as soon as the load lessens, the tubes catch their breath again.

What might at ﬁrst seem like a technical limitation of the tube amp design has turned out to be a real ben-

eﬁt for the musical expressivity of the guitarist. The KPA masters this technical behavior without degrad-

ing or changing the basic character of the amp model whatsoever.

• The ampliﬁer interacts with the guitarist and reacts to the plectrum and ﬁngers with the highest possible

sensitivity.

• The guitar sound gains extra energy and presence, without raising the perceived volume of the distorted

signal.

• Muted picking gives better results than usual, as the plectrum will not be suppressed.

• The realms of clean and distorted sounds move closer together, causing the velocity and energy of the

crunch sounds to grow. The amp doesn’t just distort everything mercilessly - instead, all of the ﬁne nu-

ances are represented faithfully. The overall sound becomes much more alive, with more punch and juice. It

almost sounds as if a compressor has been switched o, thereby allowing the guitar to establish itself a lot

easier among the other instruments on stage, such as the drums or bass.

As the dynamic range of an analog tube amp is limited by the laws of physics, power sagging can only go

to a certain level before the breakdown of supply voltage destroys the beauty of the distortion character-

istics. The KPA allows for a much wider dynamic range, while preserving the character of the tubes at the

same time.