Wiebe Cazemier wrote: > Even though it's an 192 kHz card, I noticed that mplayer played > a 96 kHz file at 48 kHz: > > This turned out a dmix thing. > > 1) Why does it resample to 48 kHz on a card that supports 192 kHz? Mixing requires that all streams use one common sample rate. dmix chooses 48 kHz (unless configured otherwise). (Try to put "defaults.pcm.dmix.rate 192000" into your asound.conf.) PulseAudio words differently; it chooses the sample rate of the first opened stream, which may or may not yield better results. > 2) Why does it resample at all when there is only one stream? Creative > cards were always bashed for doing this in hardware (to support > hardware mixing) because it reduced sound quality. That hardware resampler indeed reduced sound quality; software resamplers running on a modern CPU do not generate audible distortions. > Now that high-end cards don't do this anymore, it seems to defeat the > purpose to then put it in software. Modern cards don't do this anymore because *all* operating systems already do software mixing. > I understand it's necessary for mixing sources, but doesn't one like > to retain full quality when there is one source? This is a restriction of dmix; using one predetermined sample rate avoids communicating between multiple instances. Modern desktops use PulseAudio instead. Anyway, in what way does resampling from 192 to 48 kHz reduce quality? Are you a bat? ;-) Regards, Clemens ------------------------------------------------------------------------------ AlienVault Unified Security Management (USM) platform delivers complete security visibility with the essential security capabilities. Easily and efficiently configure, manage, and operate all of your security controls from a single console and one unified framework. Download a free trial. http://p.sf.net/sfu/alienvault_d2d _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
