firmware? so for the modules you are talking about, what you are saying is that they're virtual analog software synths anyway, and the "hardware" aspect simply provides some jacks for patching?
Think the Mutable Instruments modules, many of these are based around STM32 microcontrollers. The firmware is MIT licensed and has simply been ported into Rack modules.
There are a number of Rack modules that started out as pure hardware that now have virtual counter-parts.
I'm using it myself in combination with Ardour, now at the beginning of my learning curve - it is great!
Cardinal also contains MIT, BSD and CC0 modules. As long as all the code is compatible to GPL3.0-or-later since everything is built into a single static binary.
A lot of work has gone into due diligence in order to vet all the resources that have gone into the project: https://github.com/DISTRHO/Cardinal/blob/main/docs/LICENSES....
The value proposition that Cardinal offers by being self-contained is one of stability, backwards-compatibility and being able to easily share patches with other users without having to download or buy anything additional.
See the differences document to better understand how the projects compare: https://github.com/DISTRHO/Cardinal/blob/main/docs/DIFFERENC...
Their main model is based around having a "limitless" store where users can buy "premium" modules. And having a plugin-version that allows loading these dynamic modules. This is not something that Cardinal allows and goes straight into the philosophy of a "self-contained" audio plugin.
If anything it's an easy (and free) stepping-stone for users to try a plugin version of Rack and then buy "the real deal" when they want the full-on VCV Rack experience.
The two can easily co-exist. They can even load each other as plugins.
There are some technical issues with VCV Rack, and the lead developer is ... gently resistant to accepting patches/fixes from anyone else.
Cardinal started as an attempt to do some things better than VCV Rack does. Most people involved think it would probably have been better if those changes had been upstreamed, but that's not VCV Rack's development model.
Definitely enough for endless hours of modular patching.
I will leave it more experienced musicians :). Looks like great project
ReBirth was amazing though and would love if someone brings it back. They had an iPad version that worked pretty well but apparently Roland forced them to take it down.
One could argue that a plugin version is more than a minor feature.
Cardinal is not affiliated with VCV in any way. We use the upstream Rack source-code as a base so any support towards VCV will ultimately "trickle down" (in the form of code) back to Cardinal as well.
Cardinal is based on open-source modules (compatible with GPL3.0-or-later license) that are all compiled into a single static binary.
This is not possible with proprietary binaries.
