Cecilia5 - the audio processing toolbox

Cecilia is an audio signal processing environment. Cecilia lets you create your own GUI (grapher, sliders, toggles, popup menus) using a simple syntax. Cecilia comes with many original builtin modules for sound effects and synthesis.

Previously written in tcl/tk, Cecilia (version 4, named Cecilia4) was entirely rewritten in Python/wxPython and uses the Csound API for communicating between the interface and the audio engine. At this time, version 4.2 is the last release of this branch.

Cecilia5 now uses the pyo audio engine created for the Python programming language. pyo allows a much more powerfull integration of the audio engine to the graphical interface. Since it's a standard python module, there is no need to use an API to communicate with the interface.

User documentation

To consult the user online documentation, go to documentation.

Undo and redo

Ctrl+Z and Ctrl+Shift+Z follow one session-wide history across routing, module controls, curves, soundfiles, effects, presets, and output settings. Undo and redo reveal and focus the affected module, view, and control. Each drag or completed automation recording take is one action.

Changes that require rebuilding audio stop playback automatically; live-safe control changes keep playing. Incoming MIDI/OSC values and automation playback do not add history entries. Text fields retain their own editing undo. History holds 100 actions in memory and is cleared when opening a new session.

Requirements

• Install Python (3.11 or higher)

The programming language used to code the application.

Install with pip

Install Cecilia from PyPI:

pip install cecilia

Build packages

From the repository root, using Python 3.11 or newer:

python3 -m pip install build
python3 -m build

This creates a source archive and a platform-independent wheel in dist/. Building the wheel does not require GUI or audio dependencies.

The separate macOS application build requires py2app and the runtime dependencies. Install them into the build environment, then use scripts/builder_OSX.sh or python3 setup_py2app.py py2app.

Run from source

• Install Git

The tool needed to clone Cecilia5 source code (or you can just download a zip of the sources).

• Install dependencies (pyo, wxPython and numpy)

Windows:

py -3 -m pip install --user pyo wxPython numpy

MacOS:

python3 -m pip install --user pyo wxPython numpy

Launch the application

Open a terminal (a Command Prompt on Windows), go to the cecilia5 folder, and launch the application.

Windows:

cd path\to\cecilia5
py -3 Cecilia5.py

MacOS:

cd path/to/cecilia5
python3 Cecilia5.py

Screenshot