How to use 5.1 surround sound with NetBSD

From NetBSD Wiki

System Requirements

You will need a 5.1 Capable soundcard.
NetBSD/i386 or NetBSD/amd64 2.0 or higher
mplayer or xine software from pkgsrc.

Configuration

The soundcard should have been automatically configured by the kernel. The audiolayer is configured by

Syntax

The syntax of audioctl and mixerctl are the same.

% mixerctl
mixerctl [-d file] [-v] [-n] name ...
mixerctl [-d file] [-v] [-n] -w name=value ...
mixerctl [-d file] [-v] [-n] -a
%

Avaible command-line arguments

audioctl

% audioctl -a
name=VIA VT8233/8235
version=0x50
config=auvia encodings=ulinear:8,mulaw:8*,alaw:8*,slinear:8*,slinear_le:16,ulinear_le:16*,slinear_be:16*,ulinear_be:16* 
properties=full_duplex,mmap,independent
full_duplex=0
fullduplex=0
blocksize=16384
hiwat=4
lowat=3
monitor_gain=0
mode=play
play.rate=48000
play.channels=4
play.precision=16
play.encoding=slinear_le
play.gain=191
play.balance=32
play.port=0x0
play.avail_ports=0x0
play.seek=49152
play.samples=254935040
play.eof=3509
play.pause=0
play.error=1
play.waiting=0
play.open=1
play.active=1
play.buffer_size=65536
record.rate=48000
record.channels=2
record.precision=16
record.encoding=slinear_le
record.gain=0
record.balance=32
record.port=0x1
record.avail_ports=0x7
record.seek=0
record.samples=0
record.eof=0
record.pause=0
record.error=0
record.waiting=0
record.open=0
record.active=0
record.buffer_size=65536
record.errors=0
%

mixerctl

% mixerctl -a
outputs.master=191,191
outputs.master.mute=off
outputs.mono=255
outputs.mono.mute=on
outputs.mono.source=mixerout
outputs.surround=255,255
outputs.surround.mute=off
outputs.surround.lineinjack=on
outputs.surround.mixtofront=on
outputs.center=127
outputs.center.mute=off
outputs.center.micjack=on
outputs.center.mixtofront=on
outputs.lfe=127
outputs.lfe.mute=off
outputs.lfe.micjack=on
outputs.lfe.mixtofront=on
inputs.speaker=255
inputs.speaker.mute=off
inputs.phone=191
inputs.phone.mute=on
inputs.mic=191
inputs.mic.mute=on
inputs.mic.preamp=off
inputs.mic.source=mic0
inputs.line=191,191
inputs.line.mute=off
inputs.cd=191,191
inputs.cd.mute=off
inputs.video=191,191
inputs.video.mute=off
inputs.aux=191,191
inputs.aux.mute=off
inputs.dac=151,151
inputs.dac.mute=off
record.source=mic
record.volume=0,0
record.volume.mute=off
outputs.spatial=off
outputs.spatial.center=0
outputs.spatial.depth=0
%

Required adjustments

Dolby Digital 4.1

% audioctl -w play.channels=4
% mixerctl -w outputs.master=200,200
% mixerctl -w outputs.surround.lineinjack=on
% mixerctl -w outputs.surround.mixtofront=on
% mixerctl -w outputs.surround=200,200

You should put this into your /etc/rc.conf

Dolby Digital 5.1

% audioctl -w play.channels=6
% mixerctl -w outputs.master=200,200 
% mixerctl -w outputs.surround.lineinjack=on
% mixerctl -w outputs.surround.mixtofront=on
% mixerctl -w outputs.surround=200,200
% mixerctl -w outputs.center=200
% mixerctl -w outputs.center.micjack=on
% mixerctl -w outputs.center.mixtofront=on
% mixerctl -w outputs.lfe=200
% mixerctl -w outputs.lfe.micjack=on
% mixerctl -w outputs.lfe.mixtofront=on

You should put this also into your /etc/rc.conf

Supported Players

Mplayer

Currently mplayer has the best surround sound support. For 4.1 run

mplayer -channels 4

and for 5.1

mplayer -channels 6

Xine

Unfortunately mplayer isn't able to handle DTS recorded DVD's. The required libdts (renamed due license restrictions to libdca) is not within the Packages Collection and if you believe several mailinglists it runs currently only on linux. But xine with the sun soundriver works fine. At first you have to make some adjustments, because the sound on DTS-DVD's is sampled at 24000 Hz and not 48000 Hz as a normal stereo DVD's.

$ mixerctl -w outputs.surround.lineinjack=on
$ mixerctl -w outputs.surround.mixtofront=on
$ mixerctl -w outputs.master=200,200
$ mixerctl -w outputs.surround=200,200
$ audioctl -w play.channels=4
$ audioctl -w play.rate=24000

--Mc 14:38, 21 February 2006 (CET)

Additional Information

audioctl(1) Manpage
mixerctl(1) Manpage