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Convert Clavia Nord Modular G2 patches to the Csound code.

Project description

pch2csd - The Clavia Nord Modular G2 Patch Converter Project

The goal of this project is to (re)implement the Clavia Nord Modular G2 sound engine in Csound, a well-known sound and music computing system. Important wiki pages:


Assuming you have Python 3.5 and pip installed:

sudo pip3 install pch2csd

Before the project has got more stable, we automatically build and upload every commit made to the repository, so you may want want to update the tool once in a while. With newer versions you'll probably get new features and modules available, as well as bugs fixed. To update the tool just run the following command:

sudo pip3 install -U pch2csd


Command line options:

$ pch2csd -h
usage: pch2csd [-h] [-d] [-p | -c | -v | -e] [arg]

convert Clavia Nord Modular G2 patches to the Csound code

positional arguments:
  arg              a pch2 file path or an UDO numerical ID

optional arguments:
  -h, --help       show this help message and exit
  -d, --debug      print a stack trace in case of error
  -p, --print      parse the patch file and print its content
  -c, --check-udo  validate the UDO template file (overrides '-p')
  -v, --version    show program's version number and exit
  -e               show the elephant and exit

To generate a new Csound file just pass the .pch2 file path as the argument. The new file will be generated in the same directory with the patch file. An example:

pch2csd test_poly_mix2.pch2

Option -p can be used to print modules and cables present in of the patch. Module ID is a unique number of a module in the patch, module Type is a numerical representation of the module's type (also used to look up for templates in the resources/modules). In the square brackets are the raw MIDI module parameters. Area is the part the module or cable is located; it can be either VOICE or FX. In the cable table notation In2(id=1, out=0) -> Mix41B(id=2, in=0) means, that the cable connects the 0th output of the module In2 (ID 1) with the input 0 of the module Mix41b (ID 2). Note that the modules can connect either outputs (out-in) to inputs or intputs to inputs (in-in).

$ pch2csd -p test_3osc.pch2
Patch file: test_3osc.pch2

Name        ID    Type  Parameters               Area
--------  ----  ------  -----------------------  ------
OscA         1      97  [64, 51, 1, 0, 2, 1, 0]  VOICE
OscA         2      97  [64, 78, 1, 0, 2, 1, 0]  VOICE
OscA         3      97  [64, 64, 1, 0, 2, 1, 0]  VOICE
Mix41B       4      19  [100, 112, 91, 117, 1]   VOICE
EnvD         6      55  [54, 0]                  VOICE
FltLP        5      87  [75, 34, 0, 1]           VOICE
Out2         7       4  [2, 1, 0]                VOICE
Keyboard     8       1  []                       VOICE
FxIn         1     127  [0, 1, 1]                FX
Clip         2      61  [0, 53, 1, 1]            FX
Out2         3       4  [0, 1, 0]                FX

From                       To                  Color    Type    Area
---------------------  --  ------------------  -------  ------  ------
OscA(id=1, out=0)      ->  Mix41B(id=4, in=1)  red      out-in  VOICE
OscA(id=2, out=0)      ->  Mix41B(id=4, in=2)  red      out-in  VOICE
OscA(id=3, out=0)      ->  Mix41B(id=4, in=3)  red      out-in  VOICE
Mix41B(id=4, out=0)    ->  EnvD(id=6, in=2)    red      out-in  VOICE
EnvD(id=6, out=1)      ->  FltLP(id=5, in=0)   red      out-in  VOICE
EnvD(id=6, out=0)      ->  FltLP(id=5, in=1)   blue     out-in  VOICE
FltLP(id=5, out=0)     ->  Out2(id=7, in=0)    red      out-in  VOICE
Out2(id=7, in=0)       ->  Out2(id=7, in=1)    red      in-in   VOICE
Keyboard(id=8, out=1)  ->  EnvD(id=6, in=0)    yellow   out-in  VOICE
FxIn(id=1, out=0)      ->  Clip(id=2, in=0)    red      out-in  FX
Clip(id=2, out=0)      ->  Out2(id=3, in=0)    red      out-in  FX
Out2(id=3, in=0)       ->  Out2(id=3, in=1)    red      in-in   FX

Option -c allows you to check whether the UDO for the specified module has been implemented or has errors in the implementation:

$ pch2csd -c 43
Checking UDO for the type ID 43
Found a module of this type: Constant
The UDO template seems to be correct

$ pch2csd -c 194
Checking UDO for the type ID 194
Found a module of this type: Mix21A
ERROR Unknown table 'CLAEXP'

$ pch2csd -c 100
Checking UDO for the type ID 100
Found a module of this type: Sw21
ERROR UdoTemplate(Sw21, 100.txt): no opcode 'args' annotations were found in the template


We started our project during Summer of 2015. The Project's main objective is to simulate legendary Clavia Nord Modular G2 synthesizer using Csound language. The Project was first presented at the The Third International Csound Conference (2-4 October, St. Petersburg, Russia).

How to contribute

Please, read the file.

Why do you need it?

If you are a Nord Modular fan, this software allows you to have your favourite device ressurected for eternal life in the halls of Csound language. You also can improve the precision of models and use the whole world of Csound possibilities together with Clavia.

If you are a Csound person, this is a new branch of our journey. This is great to have some hardware digital synths running on Csound. Once the conversion project is done, you are able to use hundreds of interesting Clavia's G2 patches straigth on Csound.

If you discover the world of modular synthesis and algorithmic composition, the system provides a good way to describe the graphic patches of Clavia.

If you are a developer of alternative Clavia Nord Modular G2 Editor, you could merge your graphical editor software with the system to produce the sound.

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