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Vortex375

Member

Registered: 2009-02-24

Posts: 61

Using the ALSA ladspa plugin

Hi,

I tried to use ALSA's ladspa plugin to add some reverb to music while playing. The whole thing should run on top of PulseAudio. I followed the documentation I found here http://www.alsa-project.org/alsa-doc/al … ugins.html and set up a device in my ~/.asoundrc like this:

pcm.reverb {
    type ladspa
    slave.pcm "pulse"
    
    channels 2
    path /usr/lib/ladspa/
    
    playback_plugins {
        0 {
            id 2142  # TAP Reverberator
            policy "none"
            input {
                bindings {
                    0 "Input Left"
                    1 "Input Right"
                }
                controls {
                    "Decay [ms]" 3000
                    "Dry Level [dB]" -3
                    "Wet Level [dB]" -24
                    "Comb Filters" 1
                    "Allpass Filters" 1
                    "Bandpass Filter" 1
                    "Enhanced Stereo" 1
                    "Reverb Type" 14
                }
            }
            output {
                bindings {
                    0 "Output Left"
                    1 "Output Right"
                }
            }
        }
    }
}

Unfortunately it does not work. When I try to play audio using mplayer, it tells me:

[AO_ALSA] Unable to get initial parameters: Invalid argument

And that's all. No additional information is given about where the error occurred - even when I run mplayer in verbose mode.

aplay tells me:

aplay: set_params:957: Broken configuration for this PCM: no configurations available

Which isn't really helpful either.

How can I "debug" my asoundrc? Can anyone spot a mistake in the device's definition above?

Last edited by Vortex375 (2009-06-23 10:33:14)