An inexpensive way to get started with modular synthesis.

An open-source virtual modular synth featuring software versions of some of the most popular Eurorack modules on the market is available to download for free.

VCV Rack, which was launched at Chicago’s Knobcon event last weekend, features 30 different modules based on gear from Mutable Instruments, Befaco and Synthesis Technology, many of which feature direct ports of the software that powers the originals.

VCV Rack has one key difference over a hardware modular: control voltages and audio signals are equivalent, meaning audio signals can be used to modulate other parameters. So, for example, sonic-range VCOs can be used to create customizable FM synths or wave-shaping oscillators.

Owners of hardware modular synths can also use VCV Rack to expand their own system. As long as you have an audio interface that supports control voltage or a MIDI to CV converter, you can connect your modular using Rack’s forthcoming CV Interface device. While plenty of new modules are already planned for VCV Rack, it’s not yet possible to connect it to your DAW, though an upcoming VST/AU plug-in called Rack Bridge will make this possible.

VCV Rack isn’t the only software modular available: Native Instruments’ Reaktor Blocks and Softube’s Modular offer users their own virtual Eurorack system, but these come with a hefty price tag. VCV Rack can be downloaded for free on Linux, Mac and Windows platform, with the source code available at Github.

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