OV has a eurorack synthesizer. As of writing it looks approximately like this (→) and hangs from the ceiling.
What
A modular synthesizer breaks out the functional blocks of a synthesizer in individual modules, which can be connected to each other using some standardized interface. This means they can be rearranged and connected in different ways. Modulation in modular synths refers to using a signal from one module to control a parameter of another module or function. These values are transmitted as voltages over patch cables, and are also known as Control Voltage (CV).
Eurorack is a mechanical and electrical standard for modular synths. In eurorack, all signals are in principle the same (with some caveats), meaning that audio signals can be used as control signals.
Audio signals are generally ±5V. CV can be basically anything from ±10V, but often 0-10V or ±5V. Signal inputs will have limited voltage- and frequency ranges that they respond to, but signals outside the range will usually just get "rounded" to the nearest valid value. There are generally protections in place to prevent any excessive voltage to cause damage, as long as it's within the ±12V range of the power standard. Accidentally connecting an output to an output will also generally not cause any damage, typically an output resistor of 1k is used. The pitch control standard is 1V/octave.
One pretty cool thing about modular synths is that you can use almost any module outside of its intended purpose. Connect audio signals to control inputs or triggers, combine audio and control signals, or try self-patching a module's outputs to its inputs.
Modules
For most or all of these modules, there are several online tutorials available. There are a couple more modules in the case that I think are self-explanatory, like the "mult" which duplicates a signal. Keep in mind that you need to patch a bit before you can hear anything, see the basic modules at the top.
Mixer
Adjust volumes and combine different sounds into one signal (stereo)
Output
Plug sound here to listen on speakers (line output) or in headphones
Input
Plug sound here to amplify to a level suitable for eurorack
You can for example plug your phone headphone output in the front ("aux cable"/TRS 3.5mm)
Pamela's New Workout
Master clock and modulator
Start/stop button and tempo selector. It can also generate a bunch of different modulation in time with the tempo, such as LFOs.
A "1x" clock corresponds to the BPM. So if you want to make a 4/4 beat, 1x is quarter notes, 4x is 16th notes etc.
LMNC #1222 Performance VCO
Analog Voltage Controlled Oscillator (VCO) with tuner
LMNC #1114 Filter GRR
Funky Voltage Controlled Filter (VCF) with V.C. Amplifier (VCA)
ADDAC106 T-Noiseworks
Four Drum sound generators based on noise
This four channel module makes percussive sounds by passing noise through a T-Network filter.
Ornament & Crime
Open Source Control Voltage (CV) generator thing
This module can be programmed with different open source firmwares. As of writing, the "hemispheres" firmware is installed, which lets you control the module as two separate "halves". This can do a lot of different things, if you are just starting out I would suggest using it as an ADSR envelope generator to start somewhere.
An ADSR envelope generator is an envelope with Attack, Decay, Sustain and Release stages.
Quadrantid Swarm
Modular Synth Voice
This module can function as a standalone synth voice, meaning that it has a full "workflow" to make a sound built in.
You can also use the function blocks individually to interact with other modules. Contains:
- 8 step sequencer
- Envelope generator
- 8 digital oscillators interacting in various ways
- 2 analog filters
- Spring reverb (real)
- LFO, random generator, slew rate limiting and some more things
Looking Glass
5x5 matrix mixer/switcher with normal and inverted outputs and attenuators
Input five signals, adjust their amplitude, and route each to any of five outputs. Each output can be a mix of up to five signals. Use it either to mix modulation signals or sounds (or both???)
Steppy
Four channel trigger sequencer
A so called "XOX style" trigger sequencer, commonly found in drum machines. Press a button to toggle whether a trigger is emitted at that time. Most straightforwardly you can use it as a 16 step sequencer, but with some button combos you can sequence up to a 64 step pattern (see manual)
Clock it with a 4x clock to sequence 16th notes, etc. You can trigger drum sounds, notes, or other kinds of events. If you want it to restart when you stop the clock, you need to patch the RST signal.
More VCAs
Two Voltage Controller Amplifiers (VCA)
VCAs are a simple but important building block, they allow you to control the amplitude of one signal (IN) from 0-100% using another signal (CV IN)
Ears
Input amplifier, envelope follower and contact microphone
The knob amplifies the signal at the IN jack. You can patch e.g. a guitar or microphone here, or some random elavfall (just make sure the signal doesn't exceed ±10V). The ENV and GATE jacks give outputs that depend on the amplitude of the amplified signal. This can be used to control other parameters.
If no signal is patched to IN, the contact microphone at the bottom will be used. Try scratching the textured surface.
Pico DSP
Multi effects module. Mono input, stereo output.
Reverbs, delays and distortions. It makes your sounds sound cool and/or weird. The first parameter of each algorithm/effect can be CV controlled.
MFX
Multi effects module
Multiple effect algorithms inspired by vintage effects equipment. It's a bit clunky to configure, but it has a bunch of presets and up to 3 parameters can be CV controlled.
Try making some user presets, which can include CV control assignments.
Glossary
- ADSR: Common envelope generator with Attack, Decay, Sustain and Release stages. You will also find other combinations of the same stages such as "AD envelopes" and "AR envelopes"
- Patch: In a modular context, refers to a set of modules connected in a certain way. So for a single patch, the signal flow is the same, but you can tweak the knobs and parameters.