[pulseaudio-discuss] Module-combine adjust time question

[Lennart Poettering]

On Fri, 06.11.09 08:57, Matthew Patterson (matt at v8zman.com) wrote:

> Hello all,
> 
> I was wondering about the specifics of the adjust time option. In
> the wiki there is a comment that setting the value to 0 will cause
> no periodic sample rate adjustments ever. Does that mean that all
> sinks will remain at their default/native sample rates (and thus no
> resampling) for all time or is there an initial adjustment (and thus
> resampling) on startup? 

The former. Setting the value to 0 only really makes sense if your
audio devices are nicely in sync anyway, i.e. are hooked up to the same
clock.

> I assume this would cause the audio playback to slowly drift apart
> between sinks, but would that only be true if there was a continuous
> audio stream or would the buffering re-align every time audio stops
> and the streams go corked/silent?

Yes.

> My goal behind this question is to get max audio quality (ie
> eliminate resampling if possible) while maintaining reasonably good
> playback alignment between devices. Each playback device is in a
> different room so perfection is not necessary.

But that means you couldn't really play anything for a longer time.
i.e. that means no music and not movies... Only event sounds... And
for those you want the extra high quality?

If you care about quality simply pick the highest libsamplerate
implementation and you should be fine...

Lennart

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