oss_usb(7) OSS Devices oss_usb(7)

oss_usb - USB Audio/MIDI/Mixer driver

The Open Sound System driver for USB Audio and MIDI devices.

AUDIO The Audio driver supports:

  • 8-96Khz Playback/Recording
  • 8 or 16 or 32 bits
  • 2, 4, 6 or 8 channel audio.
  • SPDIF digital output and Input
  • AC3 passthrough
  • Volume control and device input mixer

MIDI The oss_usb driver supports all MIDI devices that are compatible with the official USB MIDI specification. In addition the driver supports few devices that use their own private protocol (including some Yamaha and Midiman models).

 USB MIXER
  The USB Audio mixer is a new type of mixer that doesn't have
  the normal volume controls found on AC97 or Legacy SB devices.
  The USB audio mixer provides control for selecting the Alternate
  device setting - this usually allows the device to be switched 
  into a Professional audio mode (eg 24bit or 96Khz mode)
 ALTERNATIVE SETTINGS
  Some USB audio devices use a feature called as alternative settings for
  bandwidth management. Typically such devices have multiple high speed
  inputs and outputs that may require more bandwidth than provided by the USB
  bus. The alternative settings feature is used to select between multiple
  low speed devices or just few high speed devices.
  When the device has multiple alternative settings an "altsetting" selector
  will be visible in the control panel for the device (use ossmix(1) or
  ossxmix(1) to change it). Alternative setting OFF means that all
  audio devices are disabled. The other settings provide different combinations
  of high/medium speed devices. You can use the ossinfo(1) command
  (ossinfo -a -v3) to find out the devices supported by the currently selected
  alternative settings and the capabilities of them.

Under Linux it is necessary to run the ossdetect -d and ossdevlinks commands after an USB device has been hot-plugged. Alternatively you can execute soundoff and soundon to reload OSS.

None

/etc/oss4/conf/oss_usb.conf
Device configuration file.

4Front Technologies

11 February 2015