From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugtrack@alsa-project.org Subject: [ALSA - driver 0001928]: Only Problems with Surround Sound Date: Wed, 15 Mar 2006 23:02:50 +0100 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from bugtrack.alsa-project.org (gate.perex.cz [85.132.177.35]) by alsa.jcu.cz (ALSA's E-mail Delivery System) with ESMTP id 42CE2203 for ; Wed, 15 Mar 2006 23:02:51 +0100 (MET) Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org A NOTE has been added to this issue. ====================================================================== ====================================================================== Reported By: the-me Assigned To: tiwai ====================================================================== Project: ALSA - driver Issue ID: 1928 Category: PCI - cmipci Reproducibility: always Severity: major Priority: normal Status: assigned Distribution: Debian Sid Kernel Version: 2.6.15.6 ====================================================================== Date Submitted: 03-15-2006 22:02 CET Last Modified: 03-15-2006 23:02 CET ====================================================================== Summary: Only Problems with Surround Sound Description: Hi. I've got a big problem ( like many other users of many other soundcards ). My Surroundsound didn't work! I've got the Terratec Aureon 5.1 Fun soundcard. At alsamixer, I haven't got any LFE or Center Options ( why? there stands in the topic *MC6 ( for 6 channels! ) ). Now I tried it with a .asoundrc. Result: Now my Rear / Front / Center worked correctly at listening to mp3s, the subwoofer ( lfe ) gives also high sound out, not only deep!!! thats a big problem. I tried it with the following .asoundrc => http://www.linux-development.org/nopaste/?800 now I found an entry at an wiki of alsa.opensrc.org , which contains following: --------------- Custom Routing of Signals to Surround Outputs With a little .asoundrc hackery, you can easily route signals around any way you like. See for example FAQ028 for an example of how to play a stereo signal over booth front and rear speakers simultaneously. The example can easily be adapted to suit your needs. FAQ028 tells us how to route our "normal" stereo signals to 4 or 5 speakers. It would be nice to process the signal for the subwoofer with a lowpass filter. Thats's where the LADSPA plugins come in handy: pcm.lowpass { type ladspa slave.pcm ... path "/usr/lib/ladspa" plugins [ { label lpf input { controls [ 50 ] } } ] } This filter will cut off everything above 50 Hz. Only problem: How do I send only one channel (a mixture of right and left channel) through this filter? And where do I send the filtered signal? I have tried this setup: # move channel 0 to channel 2 pcm.move0to2 { type route slave.pcm 3to6 slave.channels 3 ttable.0.2 1 } # 3to6 has 3 input and 6 output channels # the stereo signal is on ch. 0 and 1 # ch.0 is copied to 0 and 2 (front and rear) # ch.1 is copied to 1 and 3 (front and rear) # ch.0 and ch.1 will is mixed to ch.4 (center) # ch.2 is routed to ch.5 (subwoofer) pcm.3to6 { type route slave.pcm "surround51" slave.channels 6 ttable.0.0 1 ttable.1.1 1 ttable.0.2 1 ttable.1.3 1 ttable.0.4 0.5 ttable.1.4 0.5 ttable.2.5 1 } This seems to work from the lowpass filter to the output (I have tried aplay -D plug:lowpass sound.wav). But still the question - How to I get the data of one channel to the lowpass filter? --------------- my question, how can I set up this lowpassfilter only for my LFE channel?? I need it! mfg Patrick ====================================================================== ---------------------------------------------------------------------- the-me - 03-15-06 22:55 ---------------------------------------------------------------------- hmm, you can see this like a feature request. an alsa option to enable this in alsamixer will be good. but do you have any idea? ---------------------------------------------------------------------- rlrevell - 03-15-06 23:02 ---------------------------------------------------------------------- No, sorry, I don't. You should be able to find a sample .asoundrc for 5.1 upmixing with low pass filter for the LFE on the net though. If it was easy to enable this by default it would be done already. Issue History Date Modified Username Field Change ====================================================================== 03-15-06 22:02 the-me New Issue 03-15-06 22:02 the-me Distribution => Debian Sid 03-15-06 22:02 the-me Kernel Version => 2.6.15.6 03-15-06 22:24 rlrevell Note Added: 0008575 03-15-06 22:55 the-me Note Added: 0008576 03-15-06 23:02 rlrevell Note Added: 0008577 ====================================================================== ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642