Adjusting sound level with a LADSPA plugin
To obtain a fairly normalized sound output level independent of the input level we may use an LADSPA-pugin to filter the sound output through pulseaudio.
As a minimum we need a compressor plugin such as the dysonCompressor from the swh-plugins which need to be installed if not yet present.
After having found out the name of our default sink with
and the exact name of the plugin as it is stored in
/usr/lib/ladspa/ (with my system here
dyson_compress_1403) we can issue the following command
pacmd load-module module-ladspa-sink sink_name=ladspa_sink master=<alsa_output> plugin=dyson_compress_1403 label=dysonCompress control=0,1,0.5,0.99
<alsa_output> with the exact name of the output sink (in my system this was
The compressed output can now be listened on the newly created output sink
ladspa_sink accessible from the Sound Settings menu.
Control settings for the compressor plugin are as follows: peak limit, release time, fast ratio, ratio. See in the plugin documentation for more details, defaults and minimal resp maximal values for these controls.
To avoid clipping of playback we may also combine this plugin with a limiter after compression. We may use the
fast_lookahead_limiter for this with the master sink being now our just created lasdpa_sink from above:
pacmd load-module module-ladspa-sink sink_name=ladspa_normalized master=ladspa_sink plugin=fast_lookahead_limiter_1913 label=fastLookaheadLimiter control=10,0,0.8
Source: settings above were adapted to pulseaudio from brien's blog on miscfits