[pulseaudio-discuss] PA volume effects

[Lennart Poettering]

On Fri, 01.05.09 16:39, Colin Guthrie (gmane at colin.guthr.ie) wrote:

>
> 'Twas brillig, and Daniel Mack at 01/05/09 12:09 did gyre and gimble:
>> On Mon, Apr 27, 2009 at 06:18:59PM +0200, Daniel Mack wrote:
>>> I'm observing strange audio artefacts with my audio driver which seem to
>>> be related to audio material overamplification. IOW, the effect is only
>>> audible at waveform peaks. When I attenuate the playback volume
>>> pavucontrol, things get a lot worse - horrible distortion all over
>>> the place, even in more quite audio sections.
>>>
>>> Also, when comparing the audio output of 'aplay -Dpulse foo.wav' with
>>> 'aplay -Dplughw foo.wav', it is clearly audible that PA adds some kind
>>> of amplification to the material (I would guess ~3dB), even though all
>>> GUI accessible levels are set to 100%.
>>
>> Just for the records: this is fixed now in upstream git. Thanks a lot!
>
>
> Is this a specific change since 0.9.15 release? If so do you know if  
> there are specific commits that can be backported to a 0.9.15 build to  
> address this.
>
> I'm thinking for packagers here who are not allowed to just upgrade  
> things willy nilly, but want to provide bugfixes?
>
> Lennart is pretty good at letting people know when he pushes specific  
> commits into the fedora package which is usually a good indicator, but  
> if you've got a heads-up, it'll keep us all on our toes :D

http://git.0pointer.de/?p=pulseaudio.git;a=patch;h=d2b5ae5525e9036c4f91b1615879a5a07aac5bf2
http://git.0pointer.de/?p=pulseaudio.git;a=patch;h=3a7b287c7ebd4e1b23ab076700201d0acb5a00c2
http://git.0pointer.de/?p=pulseaudio.git;a=patch;h=076830af191306e0f6e5c6c783042345fcbca2be
http://git.0pointer.de/?p=pulseaudio.git;a=patch;h=d4b10d838a79a46f18876dbb4a3206b5e1c7bc09
http://git.0pointer.de/?p=pulseaudio.git;a=patch;h=e0f08219bb6b5ed9fd92623997074410051ed671

Lennart

-- 
Lennart Poettering                        Red Hat, Inc.
lennart [at] poettering [dot] net
http://0pointer.net/lennart/           GnuPG 0x1A015CC4