From LQWiki

A soundcard is a piece of hardware that converts signals from software into analogue or digital sound and vice versa. Soundcards are either purchased separately or come socketed on the motherboard itself, generally comprising of a microphone input socket, an audio output socket and a recording line-in socket. Soundcards also usually provide the functionality to convert MIDI files. More expensive models feature surround sound capability such as dolby 5.1 digital audio conversion. The ALSA project intends to provide sound capability for all sound cards under linux.

Contents 1 On-Board Sound 2 Sound cards that work with Linux 3 Change to order of your sound cards 3.1 Suse 3.2 Ubuntu 4 See Also

On-Board Sound

Starting with chipsets made by Intel in 1997, chipsets have had a standard interface for system manufacturers to add on-board audio through a simplified bus. The first iteration of this is called AC'97, and worked quite well for 20-bit record and playback. Over time, the specification changed for the allowance of audio risers, S/PDIF (Digital), and plug&play detection of headphones, speakers, microphones, etc.

Sound cards that work with Linux

This table lists soundcards that work with Linux. The column "Model" is what you get from calling hwinfo --sound or hwinfo --usb, respectively. The "driver" column is hwinfo's output for "Driver Modules". The "driver version" column lists the output of modinfo about the driver version. For sound recording software, see audio Recorders.

Sound card	Model	driver	driver version	driver srcversion	plays sound	records sound	plug and play
SpeedLink SL-8850 USB sound card	C-Media Electronics Audio Adapter	snd_usb_audio	-	335A8E60D827D7DA35ED24C	yes	yes	yes
Creative SB Audigy	Creative SB Audigy	snd_emu10k1	-	468501D442EE541207421BE	yes	no
82801I (ICH9 Family) HD Audio Controller		snd_hda_intel	-	F812C96290AFC279BED8E60	yes	yes, but quiet

Change to order of your sound cards

If you have more than one sound card, you may want to adjust which soundcard becomes the primary one.

Suse

With the SUSE Linux distribution, the primary sound card is /dev/dsp, the secondary is /dev/dsp1. To find out what sound card your speakers are connected to, try

dd if=/dev/urandom of=/dev/dsp

and the speakers connected to your primary sound card will make a noise. Let's imagine you have one usb sound card and one on-board sound card. Using the commands hwinfo --sound, hwinfo --usb and modinfo you find out snd-usb-audio is the driver for the usb one and snd-hda-intel is for the other one. To have the usb card as primary sound card, change /etc/modprobe.d/sound:

#options snd-hda-intel enable=1 index=0	
options snd-hda-intel enable=1 index=-2	
# u1Nb.vhmk7fPeOp7:82801I (ICH9 Family) HD Audio Controller
#alias snd-card-0 snd-hda-intel
alias snd-card-0 snd-usb-audio
options snd-usb-audio index=0

and restart your sound system with the command

/etc/init.d/alsasound restart

Then you will find /dev/dsp to be the USB sound card.

dd if=/dev/urandom of=/dev/dsp

will output sound over your usb device.

Ubuntu

For the process under the Ubuntu Linux distribution, see http://ubuntuforums.org/showthread.php?t=26280

See Also

sound