Modular synthesizers are the ultimate realisation of synthesis, bringing to mind massive facades festooned with dozens - even hundreds - of knobs and cables. These liberating instruments give the electronic musician total control over the sound design process, freeing them from the tyranny of the pre-wired signal paths of most synths.
A modular synth puts the structure of the signal path into the hands of the player, allowing them to connect modules such as oscillators, filters, LFOs, and so on, in any way they like. Want to send bursts of noise through a reverb and use the resulting signal to control LFO speed? Or modulate your filter cutoff with an audio waveform?
A modular system allows you to make those decisions and more, and today’s software modulars are even more outrageously powerful than their analogue forebears, with total recall of patches and often the provision to add as many modules as your CPU can handle - without regard to your bank balance. Plus, some of them sport modules unavailable in the hardware domain. Why settle for mere analogue oscillators when you can introduce additive or granular oscillators to the mix?
We've gathered together some of the finest modular synths on the market for this round-up, also including a selection of graphical programming environments that enable you to create your own instruments, effects and other software devices.
For a complete guide to modular synthesis, check out Computer Music issue 211 (December 2014), which is on sale now.
Native Instruments Reaktor
Reaktor is the most widely used modular music software in the world, being a modular sound design environment that can be loaded as an instrument or effect plugin, or used as a standalone application.
Despite the fact that practically any kind of audio processing, generating or sequencing tool can be developed from scratch in Reaktor, it’s actually relatively easy to use. Even if you’re a complete DSP (Digital Signal Processing) novice, Reaktor’s logical interface and straightforward design make it fun to get stuck in and design your own effects, and it’s quite possible to knock up something useful in just a few minutes.
One of the old guard of modular soft synths, VAZ first came to prominence in the late 9'0s and was among the first truly great-sounding soft synths.
As with the likes of Reaktor and Tassman, VAZ (available in three editions) has come of age in more recent years now that we’ve got the CPU grunt to really let rip with it, so don’t let the archaic looks put you off.
Cycling '74 Max/Max for Live
If you’re feeling that even the likes of Reaktor are limiting you, then the next logical step is an even deeper modular programming environment - enter Max.
Currently at version 6 going on 7, but with a lineage stretching right back to the '80s, Max edges that bit closer towards the world of straight-up text-based coding. Even better, Max For Live makes it possible to create Max patches that tightly integrate with Ableton’s famous DAW.
Synthesis is just one of Max’s many possible uses - it’s really an ultra-flexible environment for all kinds of ‘media’ work.
Another modular that’s been around for over a decade, this “sound synthesis studio” works as an instrument or an effect and relies heavily on AAS’ physical modelling technology.
Construct devices by piecing together modules in the Builder, and play ’em back in the dedicated Player environment.
Arturia Modular V
What round-up of software modulars would be complete without this? Arturia’s first ever virtual instrument - officially endorsed by Bob Moog himself - landed in our plugin folders with a thump in 2003, and it’s still a fearsome beast today, recreating that most legendary of modulars, the Moog Modular. Grab a bunch of patch cables and do Keith Emerson proud!
Madrona Labs Aalto/Kaivo
Aalto is brimming with features that provide an alternative to common methods of sound design, composition and performance. It's a semi-modular instrument, so it offers a fixed number of synthesis components, but these can be freely patched together.
Also check out its successor Kaivo, which focuses on granular synthesis and physical modelling. As you might imagine, the results are rather unlike your typical analogue modular rumblings.
Audiorealism ABL Pro
What would be the result if Roland’s iconic little TB-303 acid box got jiggy with a burly Korg MS-20? This peculiar vision must surely have been playing on AudioRealism’s mind when it crafted ABL Pro, which takes its feted 303-alike oscillators, filters and other bits, then exposes them to the user’s every whim via a full-on, patch-cable powered modular routing system.
An ideal synth for those who want modular flexibility in an easily digestible and fun form factor.
u-he’s Bazille is finally here following years of ‘coming soon’ anticipation. All that time and effort has clearly been directed at building an unsinkable modular flagship that will - mark our words - still be thoroughly relevant in a decade’s time.
Packing in digital oscillators (with ‘fractal resonance’ among their features) and analogue-style filters and effects, this beast absolutely dwarfs u-he’s previous modular, ACE, which was impressive enough itself.
Symbolic Sound Kyma
How serious are you about modular sound design? If the answer is ‘very’, then you ought to consider saving up for a Kyma system. Consisting of an external hardware DSP box and the Kyma X software environment, Kyma users can build ‘sound objects’ in a patchable modular environment and avail themselves of DSP processes that users attest are not to be found elsewhere, such as morphing from one sound to another.
As Symbolic Sound is at pains to point out, it’s not a virtual synth or instrument per se, but “a language for creating and transforming complex sounds”.
Jeff McClintock SynthEdit
This powerful PC program allows you to construct synths and effects, modular-style. You can even integrate custom modules programmed in C++, allowing the code-savvy to create highly-tailored solutions and bespoke DSP processes.
The most impressive part? You can “Save As” your creation as VST in Windows’ DLL format to create your very own VST plugins!
Xils-Lab XILS 4
What could be better than one VCS 3 modular synth? XILS-lab has the answer with its XILS 4 synth, which is basically two “integrated, interlinked and interacting” VCS 3s crammed into one synth.
Subatomic Software Audulus
Modular synths don’t always have the best interfaces, but this futuristic-looking app and Audio Unit for Mac, iPhone and iPad looks - and is! - terrific. You can port patches between iOS and desktop versions, and the AU can even host other AUs.
KarmaFX Synth modular
KarmaFX Synth easy to use, reasonably priced and provides some decidedly digital modules that are not associated with typical virtual analogue synthesis.