VM2500 Blank Panel Module 1001 VM2500 Dual Envelope Generator Module 1003 VM2500 Oscillator Module 1004-P VM2500 Oscillator Module 1004-R VM2500 Oscillator Module 1004-T VM2500 Modamp Module 1005 VM2500 Filtamp Module 1006 VM2500 Dual Noise/Random Voltage Generator Module 1016 VM2500 Oscilloscope Module 1019 VM2500 Dual Oscillator Module 1023 VM2500 Dual Reverberator Module 1025 VM2500 Preset Voltage Module 1026 VM2500 Clocked Sequential Control Module 1027 VM2500 Dual Envelope Generator Module 1033 VM2500 Sample & Hold Module 1036 VM2500 Triple VCA Module 1042 VM2500 Synthesizer Voice Module 1045 VM2500 Quad Envelope Generator Module 1046 VM2500 Multimode Filter Resonator Module 1047 VM2500 Mix-Sequencer Module 1050 VM2500 Dual Four-Channel Mixer Module 1051 VM1630 Frequency Shifter VM901 Voltage Controlled Oscillator VM901ABBB Voltage Controlled Oscillator VM902 Amplifier VM903 Random Signal Generator VM904A/B/C Filters VM905 Reverb VM907A Fixed Filter Bank VM911 Envelope Generator VM911-A Dual Trigger Delay VM912 Envelope Follower VM914 Fixed Filter Bank VM921 Voltage Controlled Oscillator VM921ABBB Oscillator Bank VM923 Filters/Noise VM927 Multiple VM928 Sample Hold VM958 Keyboard/VCO Interface VM960 Sequencer VM962 Sequential Switch VM984 Four-Channel Matrix Mixer VM995 Attenuators VM Miniverse A-440 VM Miniverse Contour VM Miniverse Filter VM Miniverse Glide VM Miniverse Mixer VM Miniverse Noise VM Miniverse Oscillator VM Miniverse Poly Contour VM Miniverse Poly Filter VM Miniverse Poly Glide VM Miniverse Poly Mixer VM Miniverse Poly Oscillator VM Miniverse Poly VCA VM Miniverse VCA VM Rackmode 10 Band Graphic EQ VM Rackmode 12 Stage Phaser VM Rackmode 3 Band Parametric EQ VM Rackmode Frequency Shifter VM Rackmode Poly Vocal Source Oscillator VM Rackmode Ring Modulator VM Rackmode String Filter VM Rackmode Vocal Source Oscillator VM Rackmode 16 Channel Vocoder VM Filtomika VM Poly Filtomika

The VM901ABBB is an oscillator bank that replicates the unique oscillator controller/slave arrangement of classic modular synthesizers. The concept is that the the Oscillator Controller module sets the overall coarse tuning as well as rectangular wave pulse width for the three slave oscillators. In the original hardware modular systems, the oscillator controller and slaves were connected internally. Any number of slave oscillators could be used, but the "one+three" combo was common, and we felt it represented a good compromise of utility and size. Though these have the appearance of four individual single-width modules, VM901ABBB is a single quad-width module. If for you need something physically narrower, use the VM901 oscillator module.

901-A Oscillator Controller

The oscillator driver is the "master control" center; all of its control settings will affect the three slave oscillators. Changing its Frequency setting will equally offset all three slave oscillators, for example.

Inputs, Outputs, and Controls

Fixed Voltage Control- Sets the range down five octaves or up six octaves.

Frequency Range- Sets the coarse frequency range to sub-audio or standard audio ranges in standard organ footages. Use the Lo setting when using VM901 as low-frequency modulation source.

Fine Tuning (0/1/2)- Allows continuously variable tuning down (0) or up (2) one octave.

Width Of Pulse Waveform- Sets the width or "duty-cycle" of the rectangular (aka, pulse) wave. It has no effect on any other waveform. Its default setting of 50% produces a perfect square wave, rich in odd-order harmonics. Moving the knob left or right narrows its width as well as the thickness of sound until it almost disappears at its extremes.

Control Inputs jacks- These are 1V/octave exponential inputs. They're used for pitch CV as well as modulating the oscillator frequency. All three jacks are the same; signals received will be summed and are multed to all three slave oscillators.

901-B Slave Oscillators

As mentioned, 901-A oscillator driver settings equally affect all three slave oscillators. Conversely, settings on individual 901-B slave oscillators are independent and have no affect on the adjacent oscillators.

Inputs, Outputs, and Controls

Frequency Range- Sets the coarse frequency range to sub-audio or standard audio ranges in standard organ footages. Use the Lo setting when using VM901 as low-frequency modulation source.

Frequency Vernier- Allows continuously variable tuning down or up by about one octave and a major third.

Sine/Saw/Triangular/Pulse output jacks- Outputs for the sawtooth, sine, pulse, and triangular waves, respectively.