Use Predefined Effect Presets in Ecasound

This guide explains how to invoke predefined effect presets on the Ecasound command line. You will learn the primary command-line syntax for applying existing presets to an audio chain, how to supply parameters to configurable presets, and how to specify custom preset definition files.

The Preset Operator (-pn)

To apply a predefined effect preset in Ecasound, use the -pn (preset name) operator within your chain setup. The basic syntax is:

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

Replace input.wav and output.wav with your respective input and output sources (such as files, ALSA devices, or JACK ports), and replace preset_name with the identifier of the preset you wish to apply.

Passing Parameters to Presets

Many Ecasound presets accept dynamic parameters to modify attributes like delay time, decay, or gain. To pass parameters to a preset, separate the preset name and each parameter value with commas:

ecasound -i input.wav -pn:preset_name,param1,param2 -o output.wav

For example, if a custom preset named simple_delay accepts delay time in milliseconds and feedback level as arguments, you would invoke it like this:

ecasound -i track.wav -pn:simple_delay,250,0.5 -o processed.wav

Loading Custom Preset Files (-pf)

By default, Ecasound searches for presets defined in standard system and user configuration files, such as /usr/share/ecasound/generic_presets.epr and ~/.ecasound/generic_presets.epr.

If your preset is saved in a custom .epr (Ecasound Preset Recipe) file outside the default search paths, load the file using the -pf option before invoking the preset:

ecasound -pf:/path/to/custom_presets.epr -i input.wav -pn:custom_effect -o output.wav

You can chain multiple presets and native effects within the same command line by specifying multiple -pn or -e flags in the order you want the signal to be processed.