Instruō Cš-L


Cš-L is a dual voltage controlled oscillator. It takes the modern approach of dual primary oscillators and expands upon them. Each oscillator sports its own wavefolder, PWM output and wide range of classic waveforms. A four-quadrant multiplier stage allows for ring modulation as well as rectified and positive only amplitude modulation. Each oscillator uses a different core (top sawtooth core, bottom triangle core) giving the best of both worlds. A versatile, definable routing modulation bus allows for CV control over a huge range of cross modulation without even needing to insert a patch cable.

In stock

SKU: INSTCSL Category: Brand:


Complex oscillators traditionally comprise of two VCOs used to generate complex waveforms. The classic configuration uses an arrangement of modulator -> carrier. Use of wavefolders enhance the timbre complexity to a ‘final’ output.

The Cš-L takes this tried and tested configuration, but blurs the lines of which voice is the carrier and which is the modulator. They can be either or both simultaneously! Each Oscillator has it’s own unique characteristics and perks, down their core circuits.

There is a wavefolder per oscillator, giving the Cš-L two entirely separate ‘final’ outputs.

Oscillator A (Top) is a sawtooth core VCO which produces sine, triangle, sawtooth and pulse outputs.
The pulse is a classic variable duty cycle waveform. The LFO button will insert a negative DC offset to the oscillator’s frequency control. This reduces the range into LFO territories. The SYNC input hard syncs the oscillator’s waveforms which allows for classic hard sync tones when running at audio rate. In LFO mode the sync input can be used to force waveform resets. Very useful when clocking LFO patterns.

Oscillator B (Bottom) is a triangle core VCO. It has a slightly different set of waveforms to A: sine, triangle, square/sub and a double pulse with variable centre pulse width. The SUB output can generate a square wave at the oscillator’s fundamental frequency, 1 octave below, or 2 octaves below. The button switches the octave and illuminates to identify the current sub state.

  • Sawtooth core voltage controlled oscillator (Oscillator A – Top)
  • Waveforms: Sine, Triangle, Sawtooth, Pulse, wavefold final
  • Triangle core voltage controlled oscillator (Oscillator B – Bottom)
  • Waveforms: Sine, Triangle, Square/Sub, double pulse, wavefold final
  • 1V/octave, Coarse and Fine pitch controls per oscillator
  • Frequency modulation input per oscillator, linear or exponential response, with attenuators
  • LFO range switch for oscillator A
  • Switchable link between 1V/octave inputs for parallel tracking
  • Multiply output with three modulator behaviour options
  • CV over each wavefolder with attenuverters
  • Symmetry offset control for each wavefolder with attenuverter

+12V: 120mA

-12V: 80mA

Depth: 42mm

Additional information

Weight 0.350 kg
Dimensions 20 x 15 x 9 cm