I don't think we are in disagreement in substance. I was trying to give a larger framework for all of those not as familiar with the general workings and decisions behind computer audio as currently implemented. "Just works" is very important to most users. But isn't right for some of us. Somewhere something does set a default samplerate and it usually is 48KHz. The alsa.config file has a setting but it doesn't seem to change anything. However, with the Hammerfall driver, for example, the driver explicitly sets the sample rate. I could not get "hw" or "plughw" to override it. And when I start up the system it always defaults to 48KHz with both the Juli@ and the Intel HDaudio drivers. It also switches to 48 between tracks in some setups and drivers. I have not found any settings that can change this and the Alsa devs have not revealed one either. However I have Alsa doing mostly what I want using "plughw". I defeated dmix since it's absolutely what I don't want. And I didn't want software volume control and any of a number of other things that would touch the audio stream. The edits of the config file to get the desired results are not easy and Alsa has a reputation for having some of the most obtuse syntax in Linux. Demian Martin Product Design Services -----Original Message----- From: Rene Herman [mailto:rene.herman@xxxxxxxxxxxx] Sent: Wednesday, June 11, 2008 10:29 PM To: Demian Martin Cc: alsa-user@xxxxxxxxxxxxxxxxxxxxx Subject: Re: Output sample rate On 12-06-08 07:13, Demian Martin wrote: > Computer audio and sample rate issues are popping up everywhere, driven > by the desire for high quality audio on PC's finally. On Windows and > Mac's its even harder to get it right. > > In Alsa (and PC audio architecture in general) the system has a default > sample rate, usually set by the driver it seems, and usually 48 KHz. Well, no. I have to comment on this since it gives the wrong impression about the design of things. ALSA drivers do not have or set a default sampling rate and whether or not "the system" does depends on you considering the dmix plugin intrinsic enough to be the system. It is enabled by default (as also said in another message just now, if the card doesn't support mixing in hardware) which means you might be tempted to view it this way, but dmix is still only a fairly recent addition and implemented just under prressure of desktop sound needing to Just Work (after which everybody goes off and uses soundserver apps exclusively anyway it seems, but oh well...). dmix is a plugin which indeed resamples to 48 kHz. It's easily disabled though by just using the "hw" ALSA device instead of the ALSA device named "default". To disable dmix from that device is also just a few config file edits away... > Normally all the audio is resampled to this rate to permit mixing audio > from different sources (the system alert noises with your MP3 playback > for instance). However for those of us trying to get very high quality > audio out of the PC it's possible to get the driver, the audio player > and the card to cooperate and play the stream at its original "bit > perfect' sample rate. It requires alignment of the audio player app > (Xine in my case), Alsa, the driver for the card (the latest version of > the Juli@ driver) and it all seems to work right after many hours of > "tweaking". You could've just disabled dmix... :-) (by editing a card config file under /usr/share/alsa/cards or overriding things in /etc/alsa.conf or .asoundrc). Rene. No virus found in this incoming message. Checked by AVG. Version: 8.0.100 / Virus Database: 270.2.0/1497 - Release Date: 6/11/2008 8:32 AM ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
