Using module-ladspa-sink - what LADSPA plugin exactly do I need to install?

[Sergei Steshenko]

If you read LADSPA specification, you'll see that in a LADSPA plugin 
there are functions that are called once per plugin lifecycle. You can 
insert into those functions fprintf(stderr, ...) calls with diagnostic 
messages to make sure the plugin is indeed instantiated/used.

For that matter, with big enough samples buffer you can insert the same 
kind of fprintf statements into the 'run' function.

Also, LADSPA plugins should be listed in the PulseAudio configuration 
file. I did manage to run a pretty sophisticated LADSPA plugin of my own 
under PulseAudio several years ago; don't have PulseAudio configuration 
file at the moment at hand right now, maybe I'll find it later.

--Sergei.

On 09/06/2024 1:07, Doron Behar wrote:
> Sorry for the late reply :) (I'm not used to mailing lists)
>
> On Mon, Jun 03, 2024 at 09:19:50PM -0700, Sean Greenslade wrote:
>> On Mon, Jun 03, 2024 at 06:17:59PM +0300, Doron Behar wrote:
>>> I found this program I'd like to use:
>>>
>>> https://github.com/pulseaudio-equalizer-ladspa/equalizer
>>>
>>> I managed to compile and run it, but I don't hear it makes a difference
>>> in the sound. Do I need to enable the `module-ladspa-sink` module? Link:
>>>
>>> https://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/Modules/#module-ladspa-sink
>>>
>>> What makes it difficult for me to figure this out myself, is the
>>> [LADSPA](http://www.ladspa.org/) link, which seems to general, because
>>> this group develop many projects, or which I'm not sure which I should
>>> compile as a pulseaudio plugin (some of which are available in my
>>> distribution.
>>>
>>> Thanks for any help in advance.
>> What distro of Linux are you running?
>>
>> Eyeballing the Arch package for this equalizer, it looks like it needs
>> the swh-plugins package for the actual LADSPA plugin itself. It might be
>> named differently on your distro.
> So I'm using NixOS and our `ladspaPlugins` package distributes the files
> distributed by Arch Linux' `swh-plugins` package.
>
>> You shouldn't need to manually load any modules in pulse; this equalizer
>> script seems to do all the module loading automagically.
> OK, sounds promising. I'm still a bit confused how it won't output any
> error if it doesn't find these plugins at all. Perhaps I'll continue to
> discuss this with upstream at:
>
> https://github.com/pulseaudio-equalizer-ladspa/equalizer/issues/58
>
> I will reply again to this thread if I'll learn something new after
> discussing there.
>
> Thanks anyway.