M 501 D

Dual Voltage 

Controlled Oscillator

This module combines two VOLTAGE CONTROLLED OSCILLATOR circuits in one double-width unit. The two oscillator halves enter a symbiosis in that they share some controls which affect both while other functions are individual to each oscillator. Each oscillator has its own octave range switch (32’...2’ plus low frequency and wide settings, ‘wide’ augmenting the range of the tune pots to the whole ten octave span of the oscillators). 

The master tune control on the left side affects both VCOs while the corresponding pot on the right controls the detune interval between VCO 1 and 2. Bipolar attenuators for frequency and pulse width modulation with their corresponding input jacks are separate as are the two pulse width controls. 

The central waveform selector controls both wave outputs 1 and 2 while three additional output jacks provide sine, sawtooth and pulse waves of oscillator 2; the output area is completed by a white noise source. More individual wave outputs can be obtained by adding the 501E expander module. The seven control voltage inputs allow control of frequency modulation and pulse width modulation of VCO 1 and 2. Two more jacks control frequency (1V/oct) while the central cv input jack controls both oscillators at once.

M 501 E

Oscillator Expander

The OSCILLATOR EXPANDER adds more inputs and outputs to the 501D dual oscillator. 

Ten output jacks provide the individual waveform outputs of 

oscillator 1 and 2: sine, sawtooth, triangle, rectangular and pulse. 

The four inputs expand both VCOs by linear frequency modulation and hard sync.

M 501 M

Oscillator Mixer

The OSCILLATOR MIXER blends the combined outputs of oscillator 1 and 2, plus three individual outputs of oscillator 1 (sine, sawtooth, pulse) and white noise. 

The attenuators allow to invert the source signals, too. Each channel has its own mute switch with a LED. 

The three out jacks provide a mixed output of both oscillator sources plus two individual outputs for vco 1 and 2 overriding the six mute switches (always ‘on’).

M 524 

Quad Voltage Controlled 

Low Frequency Oscillator

The QUAD LOW FREQUENCY OSCILLATOR module combines four voltage controlled low frequency oscillators. 

Each oscillator produces triangle and rectangular waveforms, has a frequency controller, control voltage attenuator (bipolar) and switchable frequency range (“Audio” approx. 0.5 Hz to 4500 Hz, “LFO” approx. 5 minutes/cycle to 40 Hz; these ranges can be expanded vastly via additional control voltages). 

Even though the LFOs are V/oct controllable, they are not recommended for serious VCO applications.

This module is available in CP-sized format too.

M 524 A

Low Frequency Oscillator

Assistant

The QUAD LOW FREQUENCY OSCILLATOR ASSISTANT adds three additional waveform outputs to each of the four LFOs of the attached 524 module: sine, positive sawtooth, negative sawtooth. 

The four reset input jacks allow syncing of the LFO frequency to external sources as clock pulses, gates outputs etc. 

In gate mode each LFO can be gated by external signals.