aplay -L
null
    Discard all samples (playback) or generate zero samples (capture)
pulse
    PulseAudio Sound Server
default
    Playback/recording through the PulseAudio sound server
sysdefault:CARD=NVidia
    HDA NVidia, ALC888 Analog
    Default Audio Device
front:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    Front speakers
surround40:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    4.0 Surround output to Front and Rear speakers
surround41:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Digital
    IEC958 (S/PDIF) Digital Audio Output
hdmi:CARD=NVidia,DEV=0
    HDA NVidia, HDMI 0
    HDMI Audio Output
dmix:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    Direct sample mixing device
dmix:CARD=NVidia,DEV=1
    HDA NVidia, ALC888 Digital
    Direct sample mixing device
dmix:CARD=NVidia,DEV=3
    HDA NVidia, HDMI 0
    Direct sample mixing device
dsnoop:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    Direct sample snooping device
dsnoop:CARD=NVidia,DEV=1
    HDA NVidia, ALC888 Digital
    Direct sample snooping device
dsnoop:CARD=NVidia,DEV=3
    HDA NVidia, HDMI 0
    Direct sample snooping device
hw:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    Direct hardware device without any conversions
hw:CARD=NVidia,DEV=1
    HDA NVidia, ALC888 Digital
    Direct hardware device without any conversions
hw:CARD=NVidia,DEV=3
    HDA NVidia, HDMI 0
    Direct hardware device without any conversions
plughw:CARD=NVidia,DEV=0
    HDA NVidia, ALC888 Analog
    Hardware device with all software conversions
plughw:CARD=NVidia,DEV=1
    HDA NVidia, ALC888 Digital
    Hardware device with all software conversions
plughw:CARD=NVidia,DEV=3
    HDA NVidia, HDMI 0
    Hardware device with all software conversions

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: NVidia [HDA NVidia], device 0: ALC888 Analog [ALC888 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 1: ALC888 Digital [ALC888 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0