Eurorack modular synthesizers are getting increasingly popular, especially among electronic musicians and producers. Modular synths allow musicians to create unique and complex sounds by combining different modules. The modules use patch cables to connect various modules to create a complete synthesizer voice or a unique signal path. Eurorack modular synth systems are relatively easy to get started with but do require some patience and planning to build a versatile system from the ground up. For some, this can be an exciting challenge; for others, it may feel like a lot of work for something that isn't quite as straightforward as conventional synthesizers. This blog post will cover everything you need to know before buying your first Eurorack modular synthesizer, choosing your first modules, and building your system from there.

 

What is a Eurorack Modular Synth?

Eurorack modular synths are a type of synthesizer system that allows musicians to create complex sounds by combining different modules. While modular synthesizers have been around for decades, it's only recently that Eurorack systems have grown in popularity and become mainstream. This can be attributed to Eurorack modular synths being versatile, customizable, and easy to transport. Eurorack systems typically consist of a case that holds the power supply and bus boards that distribute power to the modules. This can be a wood case, a metal case, or a frame-style chassis designed to be mounted inside of a 19" rack. The case provides housing and power for several modules connected in various ways by the user with patch cables. These modules include analog oscillators, filters, voltage-controlled amplifiers, modulation sources, effects, computer interfaces, and more. Eurorack modules come in all shapes and sizes, allowing users to create a wide range of sounds tailed to their preferences.

 

Getting Started: Things to Consider when planning a Eurorack Modular Synth

Now that you have a basic understanding of what a modular synth is and what Eurorack modular systems are all about, it's time to start building your system. While it can be tempting to just begin buying modules, there are better ways to start out. First, consider whether you will be simply sending the system MIDI notes from a sequencer or keyboard or if you will also be using the Eurorack system to generate sequences. A MIDI interface will be essential if you use external MIDI for sequencing. On the other hand, if you want to develop your musical arrangements in the Eurorack system, you will want to consider sequencers, clock dividers, logic modules, quantizers, and sources of randomness. Next, consider the style of music you want to generate. While the experimental nature of Eurorack defies some categorization of musical genre, it helps to have modules that support the basic sounds you like to use most in your compositions.

 

Choosing a case and power supply

The first thing you will want to consider is the case and power supply you will use to house your modular synthesizer. Choosing a case that is large enough for all the modules you will eventually want is essential. When I built my first system, I didn't have much of a plan starting out and quickly outgrew a 3 row, 84 HP wide system. Some cases are great for gigging, and others are more suited to staying in one place. If you plan on gigging with your Eurorack modular, look for a lightweight case with covers and durable hardware. If your case stays in the studio, you may want to focus more on aesthetics, like having hardwood sides or an ergonomic slant or curve.

 

You should also consider what power supply you will use to power your modular system. Some cases have power supplies pre-installed, while others leave that choice up to you. If you know what modules you will be buying, you can add up their total current draw to ensure the power supply you get is adequate. I like a power supply that is at least double what is required to allow extra headroom, reduce noise, and prevent overheating. The 12-volt positive and 12-volt negative voltages are separate parts of the power supply, so be sure to add them up individually. Some modules also require 5 volts, but not all power supplies provide 5 volts. Many bus boards offer 5-volt regulators on board to add this if your power supply does not have it, or you can plug in a small add-on board to add 5 volts when needed.

 

Selecting modules based on your goals and taste

While Eurorack modular systems are incredibly versatile and can create a wide range of sounds, it may take time to determine what sort of sounds you would like to make with your system. While choosing a system that fits your current musical goals, it is also important to consider your musical tastes when selecting your first system. If you like the sound of one particular synth, you may be more interested in modules that sound like the filters and oscillators in that synth than looking for something entirely new. On the other hand, if you are new to synthesizers, it can be helpful to start with a system that will be easy to understand and use while allowing you to get a feel for the sound that you can create with each module.

 

The Most Essential Module Types

Oscillators - Oscillators generate sounds, usually providing a variety of waveforms. The pitch is typically controlled with CV (control voltage) that follows a 1 volt per octave curve. This voltage can come from a MIDI to CV module, a keyboard with CV outputs, or a sequencer with CV outs.

Filters - Filters modify the sound from oscillators, usually by subtracting parts of the frequency range. Many musicians feel the filter gives sounds the majority of their character, so many systems have more filter modules than anything else.

Voltage-Controlled Amplifier (VCA) - The VCA is an amplifier controlled by an external signal. The VCA shapes the amplitude of the signals, making a continuous signal into individual notes. They are typically controlled with an envelope.

Envelope - An envelope creates a control signal that defines the shape of a note. They are usually used to control a VCA or a filter, or both at the same time. Controlling a filter with a VCA gives the sound a different frequency response over time. The most common form of an envelope is the ADSR, which stands for attack, decay, sustain, and release. The ADSR shapes the beginning slope of the sound (attack), how fast it returns to a sustained level, and how long the sound takes to die off upon the release of the note.

Low-frequency Oscillator (LFO) - An LFO is a slow oscillator that can modulate other things over time to create animation or a sense of randomness. Some LFOs are voltage-controlled, so the user can control the LFO speed with other modules, like envelopes.

 

Mistakes I made when I got started in Eurorack

Choosing the wrong case and power supply - This is one of the most common mistakes people make when they first start using modular synthesizers. Not having enough space to get different modules can severely limit your system's capability. 

Underpowering your case - Having extra power available is never a problem. But, on the other hand, having a big case where the power supply is undersized is a sure way to limit your ability to install power-hungry modules like big sequencers or vacuum tube modules or even fill the case at all! This mistake is usually easy to recover from by simply installing a second power supply.

Treating a Eurorack system the same as a keyboard - While Eurorack systems can sound like traditional synthesizers, they are capable of much more than their traditional counterparts. While you can certainly make the same sounds as a conventional synthesizer, Eurorack systems are best suited for creating unique sounds that may not be possible to make with a traditional synthesizer. Choosing the wrong modules - Another mistake many people make when they get started is choosing modules that don't do what they want to do. While it may be tempting to buy the first Eurorack module that catches your eye, it can be much more beneficial to start with a system that is easier to understand, allowing you to get a feel for the sound you can create with each module. Fashionable modules may not help you achieve your goals.

Buying too many modules right away - When I started, I bought too many modules right away. My case filled up quickly, and I wasn't thrilled with what I could do with my system. Some of the modules did not do what I thought, and I realized I missed some essential modules that I now needed more room for.

Not reading the manual first - Most manufacturers make their manuals available online. However, getting caught up in the moment and buying something without reading the manual is easy. Instead, always read through the documentation to make a more informed decision about what modules to buy. You may also discover a module is capable of even more than you realized and be able to buy fewer modules.

 

Wrapping Up

Eurorack modular synthesizers are amazing for composing and performing innovative music. They are fun to build and use and can teach you a lot about the fundamentals of music and sound. However, they are not for everyone. If you are interested in creating unique sounds and want to avoid following a set path, Eurorack modular synthesizers may be for you.