The world of modular synthesizers can be confusing and intimidating. Let’s find out what lies behind the wall of cables and why modular is back!
Contributed by Christian Moraga for the Roland Australia Blog
If you are a fan of music production or electronic music, you might have recently noticed a new instrument gracing the stages and studios of your favourite producers and musicians. This instrument (that looks more like a computer network device than instrument) features a series of knobs and jacks, buttons and switches, blinking lights and screens all hidden behind a wall of patch cables. This instrument is in fact not new, but one that is experiencing a resurgence in popularity – this is a modular synthesizer.
But what are all of those cables for? …and where is the keyboard??
The structure of the modular synthesizer is different to the now traditional keyboard synthesizer. A keyboard synthesizer comprises of oscillators, filters, envelopes and an amplifier that are all hard-wired together in a signal chain. When playing the keyboard synth, you shape the sound by altering the knobs and switches but the signal chain always remains fixed in the one path.
A modular synthesizer does not require a keyboard to be played. The basic modular synthesizer is comprised of the same blocks as a traditional keyboard synthesizer but each function is self-contained in its own “module” (hence, modular synthesizer). No module is hard-wired – each one has an input and output and the signal chain can take an infinite amount of paths. The connection of module-to-module via cables is referred to as a “patch” and the bigger the modular system, the more combinations of sounds are available to you.
The modules available in a modular synthesizer can be divided into three types; SOURCE, PROCESSOR, and LOGIC.
• SOURCE modules typically have a signal output and no signal input. These are sound sources like oscillators (VCOs) and noise sources, and also control sources like LFOs and Envelope Generators.
• PROCESSOR modules shape the sound via timbre (VCF), volume (VCA) or effects (Delay, Phaser, Ring Modulator)
• LOGIC modules provide information to control clock timings and can also be used for switching (e.g. NAND gates, clock pulse triggers).
This infinite world of sound exploration via the modular synthesizer favours the more adventurous musician. A new level of control over your sound is now available to you and is an advantage that the modular synthesizer has over traditional keyboard synths… if that is the “synthesis” path you wish to travel.A WORLD OF SOUND CONTROLLED BY VOLTAGE
On a keyboard synthesizer, to play a note you press down a key. Simple. But how do you play notes on a modular synthesizer, especially if there is no keyboard? The answer is CONTROL VOLTAGE. Let’s go back to the keyboard… When you press down a key on the keyboard synthesizer, an electronic signal is sent to the oscillator that is measured in volts. This signal controls the pitch of the oscillator, with the number of volts corresponding to the octave of the key played on the keyboard. For example, the higher the key played on the keyboard, the higher the voltage. This means, a 3V signal is one octave higher than a 2V signal, as in the image above. A signal used to control another parameter is referred to as Control Voltage or CV. In the example above 1 Volt per Octave control voltage (1V/Oct CV) is a synthesizer standard when controlling pitch in a synthesizer. Control Voltage is also used in modular synthesizers and is the way in which each module interconnects and “speaks” to each other. Each module not only has an input and an output, but also has CV inputs to control individual parameters of a module. One control voltage source can control any number of inputs like pitch, volume or cutoff, individually or all parameters simultaneously. The video below is an example of how to use an eight-step control voltage sequence in multiple ways: Control Voltage has the ability to be multiplied, combined, switched and mixed to create a random and evolving swirl of complex signals to control your modular synthesizer. This is the moment when the “beast has a mind of its own”. This serves as a source of inspiration to you as a musician to create sounds, melodies and textures you could never have imagined. On the other hand, since the modular synthesizer uses precise voltages to control parameters such as pitch and tempo, the “beast can also be tamed”. The classic Moog Modular Synthesizer was traditionally played with a keyboard to recreate more traditional instruments like flutes and horns – the modular then becomes an almost symphonic instrument. These two opposing schools of synthesis was how the world of synthesis was born with the first modular synthesis albums the very proof of that. The first modular synthesizers built in 1963, the Moog Modular Synthesizer in New York and the Buchla Modular Synthesizer in California, inspired the east-coast and west-coast schools of synthesis and shaped electronic music to come.JAPANESE MODULAR SYNTHESIZERS
ROLAND SYSTEM-700 In 1976, the Roland Corporation built the first — and only — modular synthesizer to be made in Japan – the Roland SYSTEM-700. This beast of a synthesizer featured six cabinets, a wall of modules and a five-octave keyboard –all for a measly ¥2,650,000 in Japan (roughly $12,000). The SYSTEM-700, designed for the professional studio, featured one main console (or block) that allowed for expansion with smaller blocks. Expanding a system allows for more synth “voices” to be added to the mix and for more complex sounds when using multiple control voltages. The main console consisted of:- 3 Voltage Controlled Oscillators (with four waveform outputs)
- 2 Voltage Controlled Filters (one 24dB Low-Pass and one Multi-mode)
- 2 Voltage Controlled Amplifiers (with Linear/Exponential CV)
- Noise Generator (White and Pink)
- 2 Dual ADSR Envelopes
- 2 Low Frequency Oscillators (with four waveform output and PWM).
- Ring Modulator (with selectable VCO output for {x} and {y})
- Sample & Hold (with Clock and Sample I/O)
- Spring Reverberator (with 3-channel input mixer)
- Phase Shifter (with two VCA hard-wired inputs)
- 3×2 Audio Mixers with Panning Sliders
- 2 Multiple Jack Panels
- Voltage Amplifier, Envelope Follower, Integrator (Lag Processor) Module
- Voltage Processor/Inverter
- Tuning/Test Reference Oscillator
- Monitor Section (headphones)