Modular synthesizer
Modular synthesizers are synthesizers composed of separate modules for different functions. The modules can be connected together by the user to create a patch. The outputs from the modules may include audio signals, analog control voltages, or digital signals for logic or timing conditions. Typical modules are voltage-controlled oscillators, voltage-controlled filters, voltage-controlled amplifiers and envelope generators.
History[edit]
The first modular synthesizer was developed by German engineer Harald Bode in the late 1950s.[1] The 1960s saw the introduction of the Moog synthesizer and the Buchla Modular Electronic Music System, created around the same period.[2] The Moog was composed of separate modules which created and shaped sounds, such as envelopes, noise generators, filters, and sequencers,[3][4] connected by patch cords.[5]
The Japanese company Roland released the Roland System 100 in 1975, followed by the System 700 in 1976 and the System 100m in 1979.[1]
In the late 1970s, modular synthesizers started to be largely supplanted in pop music by highly integrated keyboard synthesizers, racks of MIDI-connected gear, and samplers. By the 1990s, modular synthesizers had fallen out of favor compared to cheaper, smaller digital and software synthesizers.[1] However, there continued to be a community who chose the physically patched approach, the flexibility and the sound of traditional modular systems.
Since the late 1990s, there has been a resurgence in the popularity of analog synthesizers aided by physical standardization practices, an increase in available retro gear and interest, decreased production costs and increased electronic reliability and stability, the rediscovered ability of modules to control things other than sound, and a generally heightened education through the development of virtual synthesis systems such as VCV Rack, MAX/MSP, Pd and Reaktor etc.
Hardware offerings range from complete systems in cases to kits for hobbyists. Many manufacturers augment their range with products based on recent re-designs of classic modules; often both the original and subsequent reworked designs are available free on the Internet, the original patents having lapsed. Many hobbyist designers also make available bare PCB boards and front panels for sale to other hobbyists.
Technical specifications[edit]
Form factors[edit]
Many early synthesizer modules had height in integer inches: 11" (e.g., Roland 700), 10" (e.g., Wavemakers), 9" (e.g., Aries), 8" (e.g., ARP 2500), 7" (e.g., Polyfusion, Buchla, Serge), 6" (e.g., Emu) and width in 1/4" inch multiples. More recently it has become more popular to follow the standard 19" rack unit system: 6U (Wiard), 5U (8.75" e.g., Moog/Modcan), 4U (e.g., Serge), 3U (Eurorack).
Two 3U unit standards, in particular, are notable: Frac Rack (e.g., PAiA), which uses the entire 3U for the front panel, and Eurorack (e.g., Doepfer) which has a 2 mm horizontal lip that the front panels are seated between. Further minor variations exist where European or Japanese manufacturers round a U measurement up or down to some closer convenient metric equivalent; for example, the common 5U modules are exactly 8.75 inches (222.25 mm), but non-American manufacturers may prefer 220 or 230 mm.
Electrical[edit]
Other differences are in the plugs used, which can match 1/4-inch (6.3 mm) or 3.5 mm phone connectors, banana jacks, or breadboard patch leads; in the main power supply, which is most often ±12 V[7] or ±15 V, but can range from 2.5±2.5 V[8] to 0±18 V for different manufacturers or systems; in the trigger or gate voltages (Moog S-trigger or positive gate), with typical audio signal levels (often ±5 V with ±5 V headroom); and with control voltages of volts/octave, typically 1 V/octave, but in some cases 1.2 V/octave.
In most analog modular systems the frequency is exponentially related to the control voltage (such as 1 volt/octave or 1.2 volts/octave), sometimes called linear because the human ear perceives frequencies in a logarithmic fashion, with each octave having the same perceptual size. Some synthesizers (such as Korg MS-20, ETI 4600) use a system where the frequency (but not the perceived pitch) is linear with voltage.
Due to the continuously variable nature of knobs and sliders, reproducing an exact patch can be difficult.
There are also software synthesizers for personal computers which are organized as interconnectable modules. Many of these are virtual analog synthesizers, where the modules simulate hardware functionality. Some of them are also virtual modular systems, which simulate real historical modular synthesizers.
Computers have grown so powerful that software programs can realistically model the signals, sounds, and patchability of modular synthesizers. While potentially lacking the physical presence of desirable analog sound generation, real voltage manipulation, knobs, sliders, cables, and LEDs, software modular synthesizers offer the infinite variations and visual patching at a more affordable price and in a compact form factor.
The popular plugin formats such as VST may be combined in a modular fashion.
Hybrid modular synthesizers[edit]
Hybrid synthesizers use hardware and software in combination to realize patches. Examples include the Arturia Origin by Arturia (fully self-contained), Clavia Nord Modular and Clavia Nord Modular G2 (these need an external computer to edit patches) and Audiocubes.