Eurorack for beginners: An introduction to Modular synths

A producer friend recently showed me his new ALM Tyso Daiko Eurorack Drum Module and I was pretty impressed and thrilled with the beats we were soon cooking up. In my own studio I’ve tended to shy away from Eurorack in recent years, mostly due to time and budget constraints, but listening to the Tyso Daiko in action reminded me that I used to have a love for Eurorack and it’s a subject I always intended to cover on this website so without further ado here’s my easy guide to Eurorack to get you up to speed.

So what exactly is Eurorack?

Eurorack is a de facto standard specification of electronic and mechanical details created by Dieter Doepfer, founder of the German audio manufacturer Doepfer Musikelektronik GmbH, in the early 1990s. Eurorack allows different modules from different manufacturers to fit in the same cases and communicate with each other.

How did Eurorack originate?

To understand how what we call Eurorack today came to be we need to step back to the 1960s and the early years of modular synthesizers.

Today’s Eurorack has its origins in the modular synthesizer scene of the mid-1960s, most notably the work of the legendary Bob Moog (in collaboration with musician Herb Deutsch) and the work of Don Buchla (in collaboration with composers Morton Subotnick and Ramon Sender).

Early modular synthesizers certainly proved popular with the relatively small number of forward thinking engineers, musicians, academics and students who had access to them.

For those somewhat avant-garde musicians who were keen to push the sonic envelope, these early modular synths opened up new world’s of experimentation and sonic possibilities however modular synthesizers remained out of reach to most due to their sheer size and cost (in addition to being complicated to operate and prone to mechanical failures).

1970 saw the launch of the groundbreaking Minimoog which was a more affordable, portable version of the earlier modular Moog synthesizer. The Minimoog’s engineers in effect “dumbed down” the complexity of earlier modular synths to create something more manageable and affordable and thus it became the first synthesizer to be sold direct to the public via retail stores.

Tweaked now so that the synthesizer could reliably perform as either a melodic lead or propulsive bass instrument (rather than just as a complex sound-generating machine), the Minimoog changed everything …
David McNamee, Hey What’s That Sound: Moog Synthesizers (The Guardian newspaper, August 2010)

The Minimoog went on to became a massive hit for Moog with musicians and producers keen to get the latest electronic sounds into their music tracks and cinematic scores and it remains a much sought after synth to this day.

The 1980s and 1990s saw the birth of digital synthesizers which heralded a new era in affordable synths and cutting edge sound design and at first it looked like these newer machines would sweep away the analog, modular “dinosaurs” but modular synth enthusiasts continued to innovate and push modular synthesizers technology forward.

In the mid/late-1990s, German instrument designer Dieter Doepfer introduced his Doepfer A-100 System. The A-100 eschewed the conventions of older modular systems in favor of his own set of standards.

Doepfer’s technical specifications for his A-100 system had the advantage of being relatively easy for other enthusiasts to follow and so the A-100 systems quickly spawned a community of engineers and tinkerers creating their own unique A-100-compatible modules and many of these early adopters of the A-100 would go on to found their own Eurorack manufacturing companies.

Is Eurorack complicated?

At first glance Eurorack can look – and sound – somewhat intimidating for beginners but if you fear Eurorack is too mysterious and complicated for you to bother with then think again!

Browse any online Eurorack store and you’ll quickly discover that there are a huge number of Eurorack manufacturers creating a diverse range of modules (as of 2021 there are over 5000 Eurorack modules) many of which boast strange monikers and arcane sounding descriptions – it can be hard for a complete beginner to know what exactly these modules do, which of these modules are essential and what are the best modules to get started with.

While Eurorack might look highly technical and complicated, rest assured that almost anyone can get started exploring the possibilities of Eurorack without having a technical background or knowledge of synthesis.

Ultimately, Eurorack is mostly a “hands-on” experience that invites play and experimentation – the very best and quickest way to learn about what you can do with modular synthesis and Eurorack is to actually take the plunge, get stuck in and just play around.

Do I need to know electronics to get started with Eurorack?

Absolutely not! Knowledge is power, as they say, but you can certainly enjoy playing around with Eurorack without having any knowledge of electronics.

What is Eurorack best used for?

If you’re interested in making noises and music then Eurorack offers an infinite variety of sonic possibilities. With Eurorack you can design and build your own unique synthesizers, effects processors and even recreate classic and obsolete synths.

Eurorack also works well as an educational tool for learning various synthesis methods and can be used to introduce students of all ages into engineering, electronics and sound design in much the same way that LEGO bricks can kick start a child’s interest in design and technology.

What kind of music can I create with Eurorack?

When it comes to electronic music and Eurorack, the sky really is the limit! Eurorack enabes you to design your dream synths and explore the sonic territory you favor. As with much synth based music, the electronic nature of Eurorack modules means Eurorack users tend to create music and sounds that lean towards the experimental, the futuristic and the downright weird.

Eurorack is a great sound design and cinematic music score tool – with just a handful of suitable modules you can be creating anything from epic movie scores and haunting soudscapes to dance floor friendly club bangers.

Tips for Eurorack beginners:

When starting your Eurorack journey do start small! By starting with just a handful of modules (say, two or three at most) you’ll be able to keep costs down and you won’t be overwhelmed by the possibilities. If you’re a complete beginner avoid the temptation of maxing out your credit card(s) on lots of exotic modules.

A smaller Eurorack rig works best in terms of time to set up, troubleshooting and portability.

You can always invest in more modules as and when your musical needs evolve and your confidence grows.

Eurorack terms for beginners:

Get up to speed with Eurorack and modular synth terminology quickly with these easy to follow definitions:

Cases: You’ll use cases to house your modular synth wonder. Eurorack cases come in various sizes. The bigger your synth the bigger the case you’ll need to house it – that’s just physics!

CV: Control Voltage. Basically, everything inside a modular synth is controlled and generated via voltage.

Drum Modules: A Eurorack Drum Module creates drum and percussion type sounds. Drum modules can either generate an audio signal using a VCO ( Voltage controlled oscillator) or they can send an audio sample using a trigger.

Effects Modules: Perhaps one of the most fun aspects of any modular synth set up, effects modules process signals in interesting ways and include bread and butter sound sculpting tools such as delays, reverbs, ring modulators and phasers as well as more exotic tools for creating mind blowing and otherworldly sounds.

Envelope modules: A powerful tool to shaping audio signals Envelopes or ADSR’s (attack, decay, sustain, release) are a core element in synthesizer sound design.

Filter modules: Filters play an essential role in electronic music and you’ll likely want at least one filter module in your Eurorack rig. Filter modules cover various types of filter including low pass high pas,s band pass and multi-mode filters.

LFO: A Low-Frequency Oscillator uses a waveform (such as a square wave or sine wave) to modify the sound created by a synth’s Oscillator.

Interface Modules: Interface modules are essential for connecting your Eurorack with other studio gear including drum machines, synths, samplers, computers (and your DAW).

Modules: The heart of any Eurorack rig, modules are the parts of a rig you’ll link (or ‘patch’) together to create your pride an joy.

Mixer Modules: With a mixer module you can mix together multiple audio inputs and CV voltages. Mixer Modules vary in terms of features and complexity.

Modulator Modules: Modulate sounds with a modulator. Modulators come in a wide variety of guises of which an LFO modulator is the most common.

Patch cables: Patch cables are used to route audio signals from one part of a modular system to another. The rule of thumb is that no matter how many patch cables you buy you’ll always be one short!

Patching: The art of getting your modular synth to be more than just a useless hunk of silent modules by connecting them together in useful ways so that something ‘cool’ happens (such as you invent a new genre of techno).

Sampler Modules: Use sampler modules to play and record audio signals and manipulate samples (such as .wav files).

Sequencer Modules: Used to create sequences or patterns. Typically you’ll want a step or a matrix sequencer.

Triggers: Triggers are digital 0V to 5V pulses typically used for timing and event signalling.

Utility Modules: Utility modules mostly deal with very specific tasks such as gating, combining and splitting signals.

VCO: Voltage controlled oscillator. Analog VCOs are often relaxation oscillators which produce output signals including sine, saw, triangle and square waveforms.

VCA Modules: Voltage Controlled Amplifier (or Attenuator depending on the module). VCAs are primarily designed to control the intensity of audio signals.

Is Eurorack safe to use?

If you have ever caught a glimpse of a huge modular synth rig with hundreds – or even thousands – of colored patch cables you might wonder if such a complicated looking machine can be safe to use and tinker with.

Rest assured that Eurorack gear is perfectly safe to experiment with. Part of the fun of “playing” with Eurorack is experimenting with how many different ways you can patch modules together.

Have no fear – you can’t break a Eurocrack rig by “wrongly” patching things up and sometimes it’s just the “wrong” set up that results in the sound you’ve been searching for.

Best small Eurorack case for beginners:

If you’re going to kick things off with a small Eurorack case then check out the Intellijel Palette case and the 4MS Pods both of which will fit nicely in a typical backpack.

Typically it’s common for Eurorack cases to come with a power supply that’s capable of providing all of the voltages that your modules require.

Best Free Eurorack Software:

One easy way you can get started learning about the joys of modular synthesis is by using a Eurorack simulator on your computer.

Tennessee based developer Andrew Belt’s VCV Rack was released on September 10, 2017 after two years of development and is the best Eurorack simulator .

VCV Rack gives you access to an ever expanding library of 2000+ modules many of which are free and open source. You can also purchase premium modules, the sale of which helps fund the development of VCV Rack.

Install VCV Rack on your computer and then you can experiment with the Fundamental selection of modules – VCV Rack’s built-in collection of sound generators, processors, routers, and signal analyzers.

VCV Rack is a great way to learn the basics of Eurorack modular systems without having to spend a cent.

See the VCV Rack website to get started.

That’s it for my crash course in Eurorack – in future articles I’ll be looking at some of the best Eurorack drum modules, synths and effects money can buy!