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

The 1042 consists of three identical voltage-controlled amplifiers. Though this module was planned, it was never produced. We felt there was a need for a dedicated multiple-VCA module, so we created it for the VM2500 series. We've included Drive knobs to give them an authentic vintage ARP sound.

The idea of a voltage-controlled amplifier (VCA) is that an audio or control signal is patched to its input, then its amplitude can be externally controlled via the CV In jack. This is useful for turning audio or control signals on or off, applying envelope volume curves to sounds, regulating the amount of modulation signals applied to audio signals, and more. Think of it as a voltage-controlled gate, with a variable amount of gate opening.

Inputs, Outputs, and Controls

Drive- Replicates the inherent mild overdrive characteristics of the original ARP VCA's. At the default setting of 32%, this is very close the original, and of course can be adjusted for more or less overdrive (or way too much). "Drive" is also a really great song by The Cars, and a horrific song by Incubus, a 90s band currently residing in the, "where are they now?" file.

Amp Gain- Adds up to 5V of gain. This works in addition to incoming Amp Mod and CV 1/2/3 jack voltages. It's also useful for manually "opening" the amplifier.

Amp Mod CV in jack- Control signal inputs are patched in here. This has no attenuator and is "wide open" all the time - typically this would be used to patch an envelope generator.

CV 1/2/3 CV in jack and attenuator- Any control signal can be patched here, including gates, LFO's, sequencers, noise generators, sample and holds, etc. Audio-rate signals can also be patched in for insane ring-mod type modulation, etc. The attenuator is bipolar, with center position = no modulation.

Exp'l/Lin- These select the "curve" of the amplifier's response as the input CV rises from 0 to 5V. Lin or linear response curve is equally proportional across the voltage input range, whereas the weirdly abbreviated Exp'l or exponential curve is closer to how the human ear perceives volume. You'll likely want to use the Lin setting for modulation or control voltage situations, and use the Exp'l setting when an envelope generator is used to control an audio signal with the amplifier. Or just use whatever sounds best, we won't tell.

Input jack- Use this jack to patch in audio or control signals to be affected by the CV In jack.

Output jack- The Output jack carries the CV-modified version of the input signal.