ALC660 Surround Sound

[chazco]

Hi,

I'm trying to add 5.1 surround sound to my Ubuntu 9.10 desktop using the on-board soundcard. Everything is connected correctly using the Line-out/Mic/Line-in sockets.

On Ubuntu I do have stereo output, but nothing I've tried will make it support surround. I installed XP, where the same configuration works fine, so it's not a hardware problem.

The motherboard is a GeForce6100SM-M and the codec is a Realtek ALC660 (according to both the XP driver and Alsamixer).

Any ideas?

Thanks in advance :)

[n3had]

This worked for me

http://ubuntuforums.org/showpost.php?p=6752073&postcount=2

and then you have to choose 6ch setup on alsamixer

[chazco]

Thanks :)

Tried adding various model options to alsa-base.conf but no luck so far. It seems that Ubuntu just can't detect that the card is surround capable.

[VertexPusher]

The appropriate procedure to enable surround sound depends on which sound system you are using, ALSA or PulseAudio.

No matter which one you use, do not change the ALSA base configuration files. If you need to reconfigure ALSA, use an ".asoundrc" file in your user home directory.

[chazco]

I'm using the default setup for Ubuntu 9.10, which I think is PulseAudio. However, there are no profiles for surround in the volume control applet and editing the default-sample-channels value in /etc/pulse/daemon.conf has no effect.

[VertexPusher]

You can use speaker-test to find out if surround sound works at the ALSA level. For example, if your default sound card is card 0:

speaker-test -c 6 -D plughw:0

[chazco]

I've been using the speaker test utility (although with a different command that actually speaks the words "Front Left" etc). I only get audio from the front-left and front-right with the utility.

[VertexPusher]

I've been using the speaker test utility (although with a different command that actually speaks the words "Front Left" etc). I only get audio from the front-left and front-right with the utility.
I don't know the parameters you used for the previous tests, but if the command above doesn't give you 6 channel sound, your sound card is not 5.1 capable.

[chazco]

The command you gave doesn't give 5.1 surround...

The hardware supports it (as was confirmed by installing XP), so I'm guessing its a Linux support problem.

[n3had]

The command you gave doesn't give 5.1 surround...

The hardware supports it (as was confirmed by installing XP), so I'm guessing its a Linux support problem.

i had the same problem as i've said that already above and after doing the above trick and choosing 6ch setup on alsamixer i finally got the 6ch option on pulseaudio

EDIT: it works for ALC662 chip so i thought it may work for you too

[VertexPusher]

I'm guessing its a Linux support problem.
Unlikely. I've had several RealTek ALCxxx interfaces, and all of them were 5.1 capable on Linux.

Please run this command and copy its output here.

aplay -v -D plughw:0 -f S32_LE -r 48000 -c 6 -t raw -d 1 /dev/zero
It will play one second of silence and show a detailed description of the ALSA PCM chain used. Here's what I see (on a RealTek ALC889):

Playing raw data '/dev/zero' : Signed 32 bit Little Endian, Rate 48000 Hz, Channels 6
Plug PCM: Hardware PCM card 0 'HDA Intel' device 0 subdevice 0
Its setup is:
stream : PLAYBACK
access : RW_INTERLEAVED
format : S32_LE
subformat : STD
channels : 6
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 2688
period_size : 672
period_time : 14000
tstamp_mode : NONE
period_step : 1
avail_min : 672
period_event : 0
start_threshold : 2688
stop_threshold : 2688
silence_threshold: 0
silence_size : 0
boundary : 6052837899185946624
appl_ptr : 0
hw_ptr : 0

[chazco]

The output is:


Playing raw data '/dev/zero' : Signed 32 bit Little Endian, Rate 48000 Hz, Channels 6
Plug PCM: Route conversion PCM (sformat=S32_LE)
Transformation table:
0 <- 0
1 <- 1
Its setup is:
stream : PLAYBACK
access : RW_INTERLEAVED
format : S32_LE
subformat : STD
channels : 6
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 8192
period_size : 2048
period_time : 42666
tstamp_mode : NONE
period_step : 1
avail_min : 2048
period_event : 0
start_threshold : 8192
stop_threshold : 8192
silence_threshold: 0
silence_size : 0
boundary : 1073741824
Slave: Hardware PCM card 0 'HDA NVidia' device 0 subdevice 0
Its setup is:
stream : PLAYBACK
access : MMAP_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 8192
period_size : 2048
period_time : 42666
tstamp_mode : NONE
period_step : 1
avail_min : 2048
period_event : 0
start_threshold : 8192
stop_threshold : 8192
silence_threshold: 0
silence_size : 0
boundary : 1073741824
appl_ptr : 0
hw_ptr : 0


It works under Windows (each speaker can be tested individually) and the motherboard documentation says it's supported.

[VertexPusher]

Interesting. Apparently the plug PCM automatically performs a route conversion from 5.1 surround to 2.0 stereo. This could be due to a bug in the driver. Or it means that the card does not support 32bit samples and 5.1 output at the same time.

In case of a driver bug there is not much we can do right now, but if the card supports 5.1 with 16bit samples, there may be a way to force mixdown to 16bit/5.1 instead of 32bit/2.0.

Please try the following command:

aplay -v -D hw:0 -f S16_LE -r 48000 -c 6 -t raw -d 1 /dev/zero
This one bypasses the conversion plugin and talks straight to the H/W device, using 16bit samples instead of 32bit ones. Please copy and paste its output here.

[chazco]

Thanks for the help :)


Playing raw data '/dev/zero' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 6
aplay: set_params:984: Channels count not available


Doesn't look promising.

[VertexPusher]

Here's what I found about shared input/output connectors:

http://groups.google.com/group/comp.os.linux.hardware/browse_thread/thread/9f8cb693378130e0?hl=en

Date: Wed, 10 Nov 2004 15:11:48 +0100


Oleg Lucha wrote:
> I am on SuSe 9.0 and I have P4P800S motherboard with integrated sound.

This motherboard has shared input/output connectors, hasn't it?

> *** THERE IS NO SOUND FROM MY HEADPHONES !!! ***

The default hardware configuration is to use the shared jacks as
inputs. There are mixer controls "Surround Jack as Input" and
"Center/LFE Jack as Input" to change this.

You need at least ALSA version 1.0.3 for this; I don't know what
ships with your SuSE. (see /proc/asound/version)

HTH
Clemens
Can you find those controls in alsamixer?

[chazco]

Nope, no options related to surround in alsamixer.

[chazco]

Seems like 5.1 isn't supported on Ubuntu...

https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.22/+bug/174203

Thanks for the help anyway :)

Update: I've purchased and installed a new sound card, 5.1 surround is now working.