Does Ecasound Support Native LV2 Plugins?

Ecasound does not natively support LV2 plugins and requires a LADSPA wrapper to host them. While Ecasound includes native support for the older LADSPA (Linux Audio Developer's Simple Plugin API) architecture, it does not have a built-in LV2 hosting engine. To use LV2 effects or processors inside an Ecasound signal chain, you must bridge the LV2 plugins through a translation layer that exposes them as standard LADSPA plugins.

Ecasound’s Native Plugin Architecture

Ecasound's design relies on LADSPA for dynamic audio processing plugins. In Ecasound commands and chain setups, LADSPA plugins are called using the -el operator followed by the plugin name and its parameters. Because development on Ecasound prioritized lightweight CLI operation and stability within the LADSPA framework, native parsing for LV2 manifests, Turtle/RDF metadata, and LV2 atom ports was never directly integrated into the core codebase.

Running LV2 Plugins via LADSPA Wrappers

To execute LV2 plugins in Ecasound, you must use a wrapper such as an LV2-to-LADSPA bridge. These bridges scan your system's LV2 directory, read the plugin specifications, and generate LADSPA-compatible descriptor binaries or aliases.

Once wrapped, the plugin is accessed just like any other LADSPA plugin:

1. The wrapper exposes the LV2 plugin's audio inputs, audio outputs, and control ports.
2. Ecasound identifies the bridged plugin within the standard LADSPA search path (LADSPA_PATH).
3. You instantiate the plugin in Ecasound using the standard -el:plugin_name,param1,param2... syntax.

Limitations of the Wrapper Approach

Using an LV2 plugin through a LADSPA wrapper in Ecasound introduces several functional limitations:

• Control and MIDI Data: LV2 supports complex event types, MIDI event transport, and atom-based messaging. Standard LADSPA only supports floating-point control rates. Advanced MIDI-driven LV2 instruments and synths generally cannot be controlled properly through a LADSPA bridge.
• Graphical Interfaces: LV2 supports external and embedded user interfaces. LADSPA wrappers strip GUI components, meaning parameters must be set entirely via command-line arguments, text configuration files, or basic controller mappings.
• Dynamic Ports and State Saving: LV2 features such as dynamic port allocation, custom presets, and persistent file states are not fully mapped to the LADSPA specification and are lost in translation.

For pure audio processing tasks such as filtering, equalization, dynamic range compression, and standard delays, an LV2-to-LADSPA wrapper allows Ecasound to run modern LV2 DSP algorithms effectively.