[pulseaudio-discuss] Clevo P150HM, Realtek ALC892 and subwoofer

[Tanu Kaskinen]

On Sun, 2011-06-19 at 10:04 +0200, Julian Sikorski wrote:
> Hi,
> 
> I have recently got a Clevo P150HM laptop. It has 4 audio jacks (1 is
> SPDIF hybrid) and 2.1 speakers. Under Windows, one needs to install THX
> TruStudio Pro in order to make the subwoofer sound decent, as tested
> here [1]. Under Linux (Fedora 15 x86_64), the bass level is
> significantly worse. Is this even within the scope of PA, or should I
> talk to ALSA developers?

So the problem is simply that the subwoofer level is too low? If the
sound card is capable of doing something for that, but ALSA doesn't
expose the functionality to the userspace, then you should contact the
ALSA developers. To find out whether ALSA already supports modifying the
bass level, check the output of "amixer -c0" - does it show any controls
that might be related to the bass level? You can also tweak the controls
interactively with "alsamixer -c0".

If the sound card does support bass level controlling, and the default
setting is clearly wrong, then complain to the ALSA guys. If it's not
clear that the default setting should be something else than it is, but
you'd like to control the bass level (and you're not happy to do it with
alsamixer), then it's in Pulseaudio's domain.

If the sound card doesn't have any controls, and THX TruStudio Pro
simply does some signal processing in software, then it's definitely not
the ALSA developers' problem. The best place to do audio signal
processing would be Pulseaudio, but we don't have very great facilities
for that - module-ladspa-sink with an equalizer plugin might work, but
there's no way to enable it only when using the built-in 2.1 speakers.
Or is there, Colin and Arun? Wasn't one of you working on some kind of
dynamic filter setup?

-- 
Tanu