(Based on 
Instrument preamp with parametric EQ.
The SansAmp RPM is a versatile instrument preamp with parametric equalization and SansAmp technology. This single space rackmount model was adapted from the SansAmp Acoustic DI pedal, with the addition of a Drive control, and redesigned as an expanded multi-instrument tool. With a sweepable, semi-parametric EQ and variable gain, the SansAmp RPM is a supercharged tone shaper for any signal source. Partner it with a SansAmp RBI for the ultimate bass pre-amp system, or with a SansAmp PSA for total domination.
Drive adjusts the overall amount of gain and overdrive. Active Bass and Treble controls cut or boost ±12dB Mid Shift is a parametric EQ control that allows you to select the center frequency of the Mid control. Its sweep ranges from 170 Hz to 3.0 kHz. This, then, enables you to notch out any specific frequencies that may be causing your instrument to feed back. Mid is also an active tone control, cut or boost ±12dB. Blend allows you to mix the direct instrument signal with SansAmp Tube Amplifier Emulation circuitry. Individual Level control for the XLR out to optimize your amp's output relative to the P.A. system. Effects Loop with Mix 50/50 switch to configure in series or parallel. 1/4" rear input and XLR output with selectable levels. Buffered uneffected XLR output to run a dry signal to a separate channel. Footswitch input to engage unit. Footswitch output to chain and toggle between another SansAmp RPM or SansAmp RBI.
Based on 
