The Behringer K-2 MkII is the successful further development of the semi-modular analog synthesizer K-2, which is a clone of the famous Korg MS-20. Like the first version, the K-2 MkII is housed in the proven desktop case, which means that it can be mounted in a 19" rack with optionally available rack ears and can even be installed as an 80HP module in the Eurorack modular system. Naturally, the MkII also shines with both of the filter revisions of the time in one device. While earlier models of the MS-20 used the IC35 chip, which produced a rough, fuzz-like resonance, a cleaner circuit was used in later series, which barely colored the sine wave of the resonance.
What immediately catches the eye is that the yellowish lettering and lines are now in clear white. There are two new toggle switches in the oscillator section: VCO FM activates the oscillator FM from VCO 1 to 2 and hardsync can now be activated from VCO 1 to 2. The frequency range of the pitch control of oscillator 2 has been significantly extended, which means that the two aforementioned features now allow for even bolder sounds. The noise behavior of filter revision 1 has been roughly retained. There have also been some changes to the patch panel: a PWM CV input has been added, which enables pulse width modulation of both oscillators. An additional VCO 1+2 V/oct input finally allows the oscillators to be controlled with Eurorack-compatible control voltages. A further trigger input is used to control the envelopes.
Two analog oscillators with pulse-width modulation, ring modulator and noise generator form the sonic foundation, which is processed by the very charismatic, rough-edged, serially connected high-pass/low-pass filter and at this point at the latest is given its unmistakable sound. The modulation sources consist of two envelopes, which can be differentiated between Hold-ADSR and Delay-AR, as well as the fast LFO with variable wave symmetry; all three are permanently assigned to the oscillators and the two filters with rotary controls.
The patch field, which takes up around 2/5 of the surface, has always been typical of the MS-20. In the improved MkII version, there are 31 control voltage inputs and outputs for the various function groups, as well as an open sample & hold, an additional, freely accessible VCA and the noise generator.
Another highlight is the signal processor, which derives a bandpass sound that can be shaped in highs and lows from the incoming audio signal, recognizes the pitch and outputs it as a control voltage and generates envelope followers including trigger/gate. These five parameters wired "sensibly" to the inputs on the patch panel turn the