ST MODULAR
Karl is an analog multi-mode filter that is loosely based on the KORG MS-10 and MS-20 filters, but has been improved to handle two mono or one stereo audio source. The Resonance can still be varied independently per channel, which is very interesting when using two different audio sources at once. If you want to merge the two audio sources there is a Mix Out next to the two independent outputs per channel.
key features
Analog Dual/Stereo-Filter
4 Filter Modes: LP, HP, Phaser and Overdrive
Independent Resonance Control
Mix two Mono Signals
Mono to Stereo Converter
CV Control over Cutoff Frequency
CV Attenuator
Expander Module
Wrong Polarity Protection
specs & downloads
width: 8 HP
depth: 28 mm
power: 56 mA @ +12V / 45 mA @ -12V
videos
description / manual
Karl has four modes:
Low Pass Mode: Classic Analog Low Pass Filter
High Pass Mode: Classic Analog
High Pass Filter Phaser Mode: A small band of frequencies is filtered next to the original signal being passed through
Overdrive Mode: If Resonance is increased the filter will quickly jump to overdrive, which creates some nice Harmonics
The Modes may be changed via jumpers on the back of the module. In any mode the Cutoff Frequency may be changed via CV. The CV signal can be attenuated with the CV potentiometer.
There is also an expander module available. The „Karl Mode Selector“ gives you front panel control over the modes and an alternative audio input for the right channel that can be activated via switch.