[pulseaudio-discuss] Equalizer ... ?

[Nikita Zlobin]

In Mon, 4 Jun 2018 03:03:27 -0400
Joe <josephj at main.nc.us> wrote:

> 2) *pulse effects*: has a ton of features including systemwide EQ,
> but on my system adds noise/distortion even without any effects
> enabled (just used as a passthrough).

I use these sometimes to enhance sound from laptop dynamics. The only
issue - it makes audio systme slightly less stable. For best result you
need to normalize filter so, that no bands are bigger than +0db - or you
may have distortion occasionaly. Before EQ i have compressor (sound,
corrected by EQ is anyway going to be somewhat still), after EQ -
output limiter (another measure against distortion).

Probably, could be more optimal, yet pulseeffects is python app... :/

> Finally, you can pipe PA output to JACK and use Calf (so you don't
> have to worry about PA-mandatory applications), however this setup is
> fiendishly complex in terms of the amount of stuff you have to add to
> your audio pipeline, and if/when an application's sound doesn't work,
> you're hosed. I tried this and simply could not figure out why VLC
> worked fine but Firefox was silent.

Doesn't VLC play through jack, when it is started? Very possible, that
firefox continues trying to play via soundcard, which it is busy by
jack. If you try to run player via PA, playing to soundcard, you will
notice, that playback time doesn't even tick... In this case you have to
manually move playback and other streams to jack. Unfortunally, simple
marking of jack sink as fallback doesn't make all PA clients to use it
even after restart (probably PA remembers prefered sink/sources, what
is both feature and issue depending in case).