A modular system. A dream for many – and for many of them, an unattainable one.
Unfortunately, for those of us without particularly deep pockets, Eurorack & Co. are a pot of gold at the end of
the rainbow.
Fortunately, we are blessed with VCV Rack and other emulators, allowing us to experiment to our heart’s
content on virtually any PC. But there are no physical knobs, no direct access, and no way to quickly repatch
two cables at once during a live performance. It lacks the tactile experience.
So why not build it yourself?
Of course, you can build your own MIDI control surface to control VCV Rack. But we live in a time when you
can buy a tiny computer for EUR 5 that is capable of processing multichannel audio at studio quality.
Connecting a homemade control panel to it is just as easy as conecting it to a pc.
You could use that to build your own Eurorack modules…
But why Eurorack?
I don’t own a Eurorack system, and if I build exclusively digital modules, I don’t need analogue communication
between those modules either. That saves a fortune in converters, reduces latency and significantly improves
signal quality.
That idea gave birth to NelisRack: a digital modular system. Its purpose is to bring the advantages of the
virtual world into the physical world.
Initially, I am developing it for myself. However, I want to design it in such a way that the modules that emerge
from the project can also be built by others.
The NelisRack concept
The basic idea is simple: self-contained digital modules, each with its own processor and controls,
interconnected through digital patch connections.
A processor does not necessarily have to correspond to a single function. A module can be entirely dedicated
to one computationally demanding task, such as a complex reverb, but in many cases a single core can handle
several functions simultaneously. A module could, for example, contain four VCAs, several oscillators, or a
combination of different functions.
This allows us to make better use of the available processing power and therefore requires fewer processors.
Because combining several functions in a single module may make it practical to build modules two or even
three rows high, we are moving away from Eurorack and developing our own standard. It is based on
commonly available materials, making it easy to build a rack yourself. The exact dimensions and specifications
are part of the standard.
Once a design has proven itself in my own rack, I intend to make the source code and construction plans
available and also offer the complete module as a kit.
PatchDragon
PatchDragon is the software platform that runs on NelisRack modules and, among other things, provides the
communication protocol they use to exchange signals and data.
For communication, I want to use the same basic principle as VCV Rack: digital values represent voltages. A
signal of, for example, 5 volts therefore does not exist as an actual 5-volt signal on the patch cable, but as a
digital value representing 5 volts. PatchDragon also makes it possible to transmit multiple channels over a
single patch cable.
This means that audio, CV, gates and other signals can all be handled in the same way. It should also make it
relatively straightforward to port existing open-source VCV Rack modules to NelisRack.
The specifications, software and examples will be made available so that anyone can develop their own
compatible modules