Arch Linux

BeholdMyGlory

Member

Registered: 2008-08-30

Posts: 93

5.1 channel surround sound with ALSA; no sound with -Dsurround51

Hello,

I'm trying to get 5.1 channel surround sound working properly. At the moment it seems to be kinda working; for example when watching films the audio seems to be somewhat evenly distributed between the speakers. A problem there, however, is that when watching films or playing games I know have support for 5.1 audio, I have no idea whether the channels are actually mapped correctly to the speakers. I therefore wanted to test the speakers using the program speaker-test, as such:

$ speaker-test -c 6 -t wav

speaker-test 1.0.24.2

Playback device is default
Stream parameters are 48000Hz, S16_LE, 6 channels
WAV file(s)
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 2048 to 8192
Period size range from 1024 to 1024
Using max buffer size 8192
Periods = 4
was set period_size = 1024
was set buffer_size = 8192
 0 - Front Left
 4 - Center
 1 - Front Right
 3 - Rear Right
 2 - Rear Left
 5 - LFE
Time per period = 8.475668
...

However, with speaker-test I could only hear output from the two front speakers (whose audio, incidentally, seems to be swapped, however this may just be an issue with the 3.5mm jack->RCA cables I'm using). So, after a bit of searching I found this page instructing me to use the device surround51. But when running speaker-test as

$ speaker-test -c 6 -D surround51 -t wav

I couldn't hear any audio at all.

The ArchWiki also has an entry regarding surround sound with ALSA, however when trying that .asoundrc configuration I got:

$ speaker-test -c 6 -D dmix51 -t wav

speaker-test 1.0.24.2

Playback device is dmix51
Stream parameters are 48000Hz, S16_LE, 6 channels
WAV file(s)
ALSA lib pcm_dmix.c:1023:(snd_pcm_dmix_open) dmix plugin can be only connected to hw plugin
Playback open error: -22,Invalid argument

brebs

Member

Registered: 2007-04-03

Posts: 3,742

Re: 5.1 channel surround sound with ALSA; no sound with -Dsurround51

You probably need the usual model= option for snd-hda-intel.

pigiron

Member

From: USA

Registered: 2009-07-14

Posts: 150

Re: 5.1 channel surround sound with ALSA; no sound with -Dsurround51

Also, try the example found in the speaker-test man page:

  Produce 5.1 speaker sound from three stereo jacks:
          speaker-test -Dplug:surround51 -c6

With ALSA, when you put the "plug:" keyword before the device name, the ALSA code will attempt to dither/resample the incoming audio data to fit the hardware audio device capabilities. If you omit the "plug:" keyword, you're sending the audio data directly to the hardware, which it may, or may not, be capable of playing.

gyurman

Member

From: Budapest/Hungary

Registered: 2011-03-22

Posts: 68

Re: 5.1 channel surround sound with ALSA; no sound with -Dsurround51

I have same problem. Everytime I get only front sound, or alsa problems. Could you solve it?