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ezzetabi

Member

Registered: 2006-08-27

Posts: 947

Using all channels of my audio card?

May useful information...

$ uname -a
Linux nakoruru 2.6.22-ARCH #1 SMP PREEMPT Thu Aug 2 17:32:20 UTC 2007 x86_64 Intel(R) Core(TM)2 CPU         T7200  @ 2.00GHz GenuineIntel GNU/Linux
$ lspci | grep Audio
00:1b.0 Audio device: Intel Corporation 82801G (ICH7 Family) High Definition Audio Controller (rev 02)
$ lsmod | grep snd
snd_seq_oss            32896  0 
snd_seq_midi_event      7808  1 snd_seq_oss
snd_seq                55680  4 snd_seq_oss,snd_seq_midi_event
snd_seq_device          7956  2 snd_seq_oss,snd_seq
snd_pcm_oss            44576  0 
snd_mixer_oss          16896  1 snd_pcm_oss
snd_hda_intel         347940  3 
snd_pcm                82568  3 snd_pcm_oss,snd_hda_intel
snd_timer              22536  3 snd_seq,snd_pcm
snd                    57064  12 snd_seq_oss,snd_seq,snd_seq_device,snd_pcm_oss,snd_mixer_oss,snd_hda_intel,snd_pcm,snd_timer
soundcore               7968  1 snd
snd_page_alloc          8720  2 snd_hda_intel,snd_pcm
$ hwdetect --show-sound
SOUND  : snd-mixer-oss snd-pcm-oss snd-page-alloc snd-pcm snd-timer snd snd-hda-intel soundcore
$ aplay -L
default:CARD=Intel
    HDA Intel, ALC883 Analog
    Default Audio Device
front:CARD=Intel,DEV=0
    HDA Intel, ALC883 Analog
    Front speakers
surround40:CARD=Intel,DEV=0
    HDA Intel, ALC883 Analog
    4.0 Surround output to Front and Rear speakers
surround41:CARD=Intel,DEV=0
    HDA Intel, ALC883 Analog
    4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Intel,DEV=0
    HDA Intel, ALC883 Analog
    5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Intel,DEV=0
    HDA Intel, ALC883 Analog
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=Intel,DEV=0
    HDA Intel, ALC883 Analog
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=Intel,DEV=0
    HDA Intel
    IEC958 (S/PDIF) Digital Audio Output
null
    Discard all samples (playback) or generate zero samples (capture)

If I start alsamixer I can see an item called Channel mode: 2ch, I can't change it. But reading around I understood my sound card should manages 5 (or even 7) chs... What can I do to use all speakers?

Edit: messing a little I tried speaker-test -c8 -Dsurround51(71) and I have: Playback open error: -16 Device or resource busy. I am not using the sound... :S

Last edited by ezzetabi (2007-08-03 17:10:00)

Mikko777

Member

From: Suomi, Finland

Registered: 2006-10-30

Posts: 837

Re: Using all channels of my audio card?

Well lemme clear this one up for you

Basically if you connect through spdiff to your amplifier its always 2ch stereo (PCM) or encoded digital stream like AC3 DTS and so on...

There are very few soundcards as far as I know that can encode digital surround sound on the fly, so you need to have it pre-encoded, ie the soundtrack from the movie etc and send it to spdiff-passthrough for your amp to handle.

Another case would be the analog jacks in your soundcard in which case encoding wouldn't be needed, but application support would be necessary to decode the multichannel stream to apropriate channels/outputs.

How thats done I have no idea.

---

Planet KDE | Opendesktop.org | Chakra Project

ezzetabi

Member

Registered: 2006-08-27

Posts: 947

Re: Using all channels of my audio card?

I think I understood... more or less... but speaker-test -c6 -Dsurround51 should send the sound in every channel anyway,,, why it does not?

Hohoho

Member

Registered: 2007-06-23

Posts: 222

Re: Using all channels of my audio card?

speaker-test -c6 -Dsurround51 works for me nicely on my Audigy 2, 5.1 speaker setup plugged in through analog.

Perhaps this has something to do with your soundcard not being able to do hardware mixing? (Im not sure if it can or cannot)

ezzetabi

Member

Registered: 2006-08-27

Posts: 947

Re: Using all channels of my audio card?

In the other computer I do have a Audigy 2 and it works to me too. In other computer I have this Inter card and it does not... :S