The Elusive French Legend, Introducing the Kobol Expander (Part One)
Historical all-rounder
The Kobol Expander from Behringer is a compact clone of the very rare rack synthesizer of the same name from the French company RSF (Ruben & Serge Fernandez), which was once produced and 1979. At that time, the Kobol Expander had come on the market as a compact and at the same time extended rack version of the keyboard Kobol. unique at least for that time was the possibility to continuously crossfade the waveforms of the oscillators, resulting in variants that separately selectable waveforms can not offer. In addition, there are 32 inputs and outputs for CV, Gate and audio; almost every control can be modulated via control voltage and every function has an output. This makes the Kobol Expander incredibly versatile when patched with itself, add a Moog modular system as possible back then or a few Eurorack modules today and this synthesizer is a serious capacity in flexibility and sound.
An analogue powerhouse
The analog sound generation of the Kobol Expander is based on American models of the late 60s, but has some special features that give this synthesizer a unique selling point. The Kobol Expander from Behringer is also equipped with two oscillatorswhose waveforms can be crossfaded. The volume of the oscillators is not simply adjusted, but can also be modulated thanks to a VCA before the signal enters the filter. If you patch the second oscillator into the volume input of the first oscillator, amplitude or sideband modulation is created. Other sound sources are a noise generator with white and pink noise and the audio input for external signals. Additionally, hardsync is switchable between the oscillators and the frequencies, as well as the waveforms, and can be modulated via control voltage. The next element in the signal path is a resonant 24dB Lowpass filter, which thrilled then as now with a very distinctive sound and thus contributes in a significant way to the overall sound. The final element is a fast-reacting VCA with mono audio output. Two fast ADS (Attack / Decay / Sustain) envelopes for VCF and VCA as well as an LFO with triangle and square waveform act as classic modulation sources. The envelope parameters and the LFO frequency can also be modulated via CV. A simple Voltage Processor is used to mix and invert control voltages. It actually takes a little imagination to convert the possibilities offered by the 32 sockets into sounds, but once you understand it, the Kobol Expander can take on many a modular system.
The back of the Kobol Expander
Features:
Manufacturer:
Behringer
Construction / Number of Keys:
Desktop without keyboard
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