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Modular synth rack

Cardinal

Physical Eurorack modules can be expensive, and you need the space and time to build your own configuration. The software emulation of Eurorack created by VCV Rack solved all these problems, and consequently became hugely popular. Many physical modules were recreated within VCV. Thanks to so many being open source, software recreations could run exactly the same firmware as their physical counterparts. VCV became very successful, and the module library expanded into its own store where commercial and proprietary recreations could be offered alongside the community-developed one. VCV Rack then became VCV Rack Pro, which ultimately became closed source. The project's ambition started to generate some friction within the original community, especially when conversations turned towards expansions and reworking VCV into a plugin that could be used within your favorite audio software. The external module library made this difficult, and also allowed the host project, VCV Rack, to exert a level of control that felt out of balance with the developers creating the modules. But the base was still open source, and the ideal community solution was to create a fork that would reflect their values while also hopefully staying on friendly terms with the original project. Cardinal is that fork.

It's been over two years since then. Cardinal is now a well-established VCV alternative that puts open source at the heart of its mission. It's been able to do this by completely re-engineering the external module system to create a self-contained single binary system that's better suited to both the spirit of open source and the way audio plugins are expected to work. The Linux-friendly LV2 format, for example, has been supported from the very beginning, and Cardinal is now available as a CLAP, VST2, VST3, and Audio Unit plugin, across Linux, Windows, and macOS. There are different plugin types too, depending on which kind of sounds you want to play with. These are "main," "synth," and "fx," designed to enable the full version with eight outputs, or with two output versions built for sound design and effects processing respectively. There's also a "mini" variant with a limited module selection. This self-contained approach means Cardinal can better support multiple architectures, including builds for ARMHF and ARM64, RISC64, and even FreeBSD!

This doesn't mean you'll need to forgo the huge VCV Rack library, either, because Cardinal bundles 1,079 modules into a single file, including replacement for all the core Rack modules, some internal utilities, and many third-party modules. Creating and processing sounds in Cardinal is also the same experience, albeit within a completely different themed and rebranded environment. Inputs and outputs consist of audio, MIDI, and control voltages (CVs). While every module is different, oscillator modules will have the same CV control for frequency and waveform control. There are hundreds of variants, and you can connect and interconnect everything with virtual patch cables and save your configuration in a way that's just not possible with the real hardware. There's even a dark theme, which the original doesn't offer, and support for control voltage in and out to real hardware, outside the software realm. If you have a compatible CV or audio interface, this means you can integrate the control signals from your external Eurorack modules with the control signals in your virtual software Eurorack, which is another amazing addition, making Cardinal the default choice if you want to play with virtual Eurorack modules.

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