Save Ecasound LADSPA Chains as Presets

Ecasound allows users to encapsulate complex processing chains—including LADSPA plugins—into standalone, reusable presets. While Ecasound operates primarily as a command-line and scriptable audio tool without a graphical "export" dialogue, it natively supports defining effect presets through configuration files and exporting complete chainsetups using interactive commands. This article outlines how to create, save, and load custom LADSPA plugin chains as standalone presets in Ecasound.

Understanding Ecasound Preset Formats

Ecasound provides two primary ways to store and reuse LADSPA chains:

1. Effect Presets (.ecp files or ecasoundrc): These define specific sequences of audio effects, LADSPA plugins, and controllers that can be assigned to any individual chain.
2. Chainsetups (.ecs files): These store the complete routing configuration, including inputs, outputs, chains, controllers, and LADSPA plugins across the entire session.

Method 1: Creating Standalone Effect Presets (.ecp)

To create a modular preset focused strictly on an effect chain containing LADSPA plugins, use an Ecasound Preset file (.ecp) or add the definition to your user configuration file (~/.ecasound/ecasoundrc).

1. Create a text file with an .ecp extension, such as my_ladspa_chain.ecp.
2. Define the preset name and the chain of LADSPA plugins using the -el (LADSPA effect name) or -eli (LADSPA plugin ID) operators, followed by their parameters:

# Define custom preset containing two LADSPA plugins
my_compressor_reverb = -el:sc4,0,100,50,-10,4,2,0 -el:freeverb,0,0.5,0.5,0.8,0.2

3. To make the preset globally available across all sessions, append the definition directly to ~/.ecasound/ecasoundrc.

Method 2: Exporting from Interactive Mode (cs-save)

If you configure an effect chain interactively within the Ecasound Interactive Audio Mode (EIAM), you can export the setup directly to disk as a .ecs file:

1. Launch Ecasound in interactive mode:

   ecasound -c

2. Add your desired chain and attach LADSPA plugins:

   c-add chain1
   c-select chain1
   -el:ladspa_plugin_name,param1,param2

3. Export the setup using the cs-save command:

   cs-save my_chain.ecs

This creates a standalone configuration file containing the routing and the exact LADSPA chain parameters.

Loading and Reusing the Preset

Once defined, you can apply your preset in new audio sessions using the preset-selection flags:

• Using a preset from an external preset file:

  ecasound -i input.wav -pf:my_ladspa_chain.ecp -pn:my_compressor_reverb -o output.wav

• Using a preset stored in ~/.ecasound/ecasoundrc:

  ecasound -i input.wav -pn:my_compressor_reverb -o output.wav

• Loading a saved chainsetup file:

  ecasound -s:my_chain.ecs