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ALSA
If you're lucky, alsa should work without much work or at least the default gnome mixer should let you select the correct input / output. However, it is not uncommon for PC to have multiple audio devices and the list of output devices will not fit in one screen. My advice is to remove the unused devices such as a usb audio headset when it's not needed.Run speaker-test
As always, cli is your friend once you get acquainted. speaker-test is a nice tool to test your output. First, find your output devices:> aplay -L default Playback/recording through the PulseAudio sound server pulse Playback/recording through the PulseAudio sound server front:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog Front speakers surround40:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog 4.0 Surround output to Front and Rear speakers surround41:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog 4.1 Surround output to Front, Rear and Subwoofer speakers surround50:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog 5.0 Surround output to Front, Center and Rear speakers surround51:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog 5.1 Surround output to Front, Center, Rear and Subwoofer speakers surround71:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog 7.1 Surround output to Front, Center, Side, Rear and Woofer speakers iec958:CARD=SB,DEV=0 HDA ATI SB, ALC892 Digital IEC958 (S/PDIF) Digital Audio Output dmix:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog Direct sample mixing device dmix:CARD=SB,DEV=1 HDA ATI SB, ALC892 Digital Direct sample mixing device dsnoop:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog Direct sample snooping device dsnoop:CARD=SB,DEV=1 HDA ATI SB, ALC892 Digital Direct sample snooping device hw:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog Direct hardware device without any conversions hw:CARD=SB,DEV=1 HDA ATI SB, ALC892 Digital Direct hardware device without any conversions plughw:CARD=SB,DEV=0 HDA ATI SB, ALC892 Analog Hardware device with all software conversions plughw:CARD=SB,DEV=1 HDA ATI SB, ALC892 Digital Hardware device with all software conversions
Believe me this is already quite short. If you want to remove certain output devices, you can add them to the modprobe blacklist. Going back to speaker-test, suppose I want to see if my DAC supports 192Khz output, I can do:
# speaker-test -Diec958:CARD=SB -c2 -r96000 -l1 speaker-test 1.0.24.2 Playback device is iec958:CARD=SB Stream parameters are 96000Hz, S16_LE, 2 channels Using 16 octaves of pink noise Rate set to 96000Hz (requested 96000Hz) Buffer size range from 64 to 16384 Period size range from 32 to 8192 Using max buffer size 16384 Periods = 4 was set period_size = 4096 was set buffer_size = 16384 0 - Front Left 1 - Front Right Time per period = 5.804195
As it turns out, when I increase the output rate to 192kHz, I hear nothing.
Customizing alsa
I set my default alsa device to be the digital out and I want all sound to be output at 96kHz. Not sure if this is effective tho:# cat /etc/asound.conf
defaults.pcm.dmix.rate 96000
pcm.!default {
type hw
card 0
device 1
}To restart alsa without rebooting
/sbin/alsa force-reload
Some useful links
https://wiki.archlinux.org/index.php/Advanced_Linux_Sound_Architecture#Getting_SPDIF_Outputhttp://linux.dsplabs.com.au/alsamixer-and-alsactl-store-adjust-and-save-alsa-mixer-settings-p29/
http://www.mythtv.org/wiki/Using_ALSA%27s_speaker-test_utility
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