Provided by: oss4-base_4.2-build2004-1ubuntu2_i386
oss_sblive - Creative Labs Sound Blaster Live/Audigy family driver.
Open Sound System driver for Creative Labs Sound Blaster Live!, Audigy,
Audigy2, Audigy2-Value and sound cards.
The sblive driver supports:
o 8-48Khz Playback/Recording
o 8 or 16 bits
o SPDIF digital output and Input
o Multi channel 5.1 (Live!) and 7.1 (Audigy) output.
AC3 passthrough is only supported on Audigy series of the soundcards.
OTHER SIMILAR CARDS
There are several Sound Blaster cards that are also called as Live or
Audigy. However these cards are based on entirely different hardware
design and they are not compatible with this driver.
o Sound Blaster Live 5.1 card is used in some Dell machines but it's
driven by the emu10k1x driver.
o Sound Blaster AudigyLS and Live 7.1 models are driven by the
audigyls driver of OSS.
SBLIVE COMBO SPDIF AND AUDIO JACKS
Most models of Live! and Audigy cards have an orange combo jack that is
used both for the analog center/LFE output and for digital DIN (S/PDIF)
output. The output mode is selected by a driver configuration option
(seel below) which should be set to proper value depending on the
actual speaker configuration.
o Noisy analog center/LFE output. The orange combo jack at the rear
plate of the Live/Audigy card is shared between the digital DIN and
the analog center/LFE outputs. In digital DIN mode (default) you
will hear very noisy output from the speakers connected to this
output jack. If you have analog center/LFE (subwoofer) speakers
connected then you need to turn off the sblive_digital_din (or
o There is a new configuration option to enable/disable the "digital
DIN" output. By default the digital DIN interface is enabled which
disables the center/LFE analog output (uses the same combo jack). By
setting the sblive_digital_din (or audigy_digital_din) option to 0
you can enable the analog C/LFE output feature. When digital DIN is
disabled you can still get S/PDIF (or AC3) output from the digital
(optical/coax) outputs of the optional livedrive unit.
SB Live cards have actually two mixer chips. In OSS both of them are
controlled together. However only limited set of features can be
controlled using ordinary mixer programs (such as the mixer applet
included in OSS). Majority of features can only be accessed using the
ossmix and ossxmix programs included in OSS.
The AC97 mixer is used to control volumes of the back bracket inputs
(mic and line in) and the _analog_ CD input connector on the soundcard.
The 'mic' volume controls the level of the rear bracket microphone
input sent directly to the front (only front) speakers. The 'line' and
'cd' controls do the same for the back bracket line in connector and
the on board analog CD input connector. It's usually recommended to set
these volumes to 0.
Another function of the AC97 mixer is selecting the signal that is
passed to the master mixer (for example for recording). One of the
'mic', 'line' or the recording source in the AC97 mixer. The 'rec'
volume control slider can be used to adjust the signal strength. The
'igain' control doesn't usually have any effect but some hardware
revisions may use it for controlling the microphone recording level.
SBLIVE MASTER MIXER
Other mixer functions are handled by the DSP engine of the EMU 10k1
chip. Most input signals (including all digital signals and LiveDrive
There are only two master mixer settings that can be controlled using
all mixer programs. The 'vol' setting is the master output volume that
affects both the front and rear speakers and the headphone output
(digital output volumes are not affected). The 'pcm' setting controls
volumes of all PCM playback channels (/dev/dsp#).
In addition to volume sliders most inputs have a stereo VU meter pair
(only in ossxmix) that can be used to monitor the input and to adjust
the input levels properly.
The master mixer consists of several sections that are:
o Primary section: This section has two settings. The "spkmode"
setting selects how front/rear speakers are used for PCM playback
(outputs from programs using /dev/dsp#). The possible settings are
FRONT, REAR and FRONT+REAR. The default is FRONT+REAR. Change this
setting if you like to get PCM playback only from front or rear
speakers. The "autoreset" flag is used to control the "/dev"
o "/dev" section: This section controls the volumes of each /dev/dsp#
device file supported by the device (there are 8 of them at this
moment). These volumes will return back to maximum every time the
device is opened. However this can be disabled by setting the
'autoreset' option to OFF. The ossxmix program has special ability
to show the application using the particular /dev/dsp device (for
layout reasons only the first 4 characters of the program name are
o The equalizer section: This section controls the graphic equalizer
for front speakers only.
o The front rear, and record sections: These three identical sections
control the levels of external inputs and PCM playback (/dev/dsp#
devices) to be sent to the front/rear speakers and to the recording
device. The CD Analog audio will only be heard from the FRONT
Before recording anything you need to set the volumes in the recording
section properly. To enable recording from the AC97 connected inputs
(mic, line in and analog CD) use the AC97 mixer to select the desired
input and then tune the input level using the rec (and igain) setting.
Finally set the 'ac97' slider in the record section of the master mixer
so that the recording level is suitable.
The OSS drivers permit recording any application that's currently
To record audio that's playing on any of the SB Live channels:
o Turn down the AC97 control in the "record" section. This prevents
any audio being fed to the soundcard from MIC/Line-in/CD-in from
getting mixed with the audio produced by the application that's
o Type ossrecord -s<sampling rate> -b<bits/sample> -c<channels>
o To stop recording press <Ctrl-c> and then you can play back the
test.wav file using ossplay command.
RECORDING ISSUES: In most cases noise is caused by the microphone input
or some other (unused) input. Use the ossxmix program to turn off all
unused inputs and finally save the current mixer settings (see below).
WARNING! If you turn off some of the signals in recording section or
the AC97 mixer section this affects all subsequent recordings. Remember
to raise the volume prior doing any recording. After that decrease the
volumes again if necessary.
SBLIVE HARDWARE MIXING
You can use /dev/oss/oss_sblive0/ pcm0-pcm7 to play multiple audio
programs using the hardware mixing. Simply specify the device name
with the application. A simple test is to do the following: ossplay
-d/dev/oss/oss_sblive0/pcm0 <file1.wav> & ossplay
-d/dev/oss/oss_sblive0/pcm1 <file2.wav> & ossplay
-d/dev/oss/oss_sblive0/pcm2 <file3.wav> &
You should hear all three wav files playing simultaneously.
NOTE: Some apps may desire the old /dev/dspN names. e.g. /dev/dsp0 -
NOTE: You can increase the number of output devices from the standard 8
devices to 32 device. For this, run soundconf, select Set configuration
options and look for the entry "sblive_device", now type any number
between 1 and 32 for the number of channels you wish. You can also do
this manually by editing oss_sblive.conf and inserting
sblive_devices=XX entry, e.g.: sblive_devices=27
There are two alternative ways to connect audio signal from a CD-ROM
drive tor the SB Live soundcard. You can use a (three wire) analog
cable or a (2 wire) digital cable. OSS now supports both of these
choices. Note that there are separate mixer settings for both of these
The analog CD-ROM wire is connected to the AC97 code chip and this
method works in most cases. To route the analog CD -input to the
(front) speakers you need to raise the volume of the 'cd' control in
mixer. However if you like to hear the analog CD input both from the
front and rears speakers you need to do this in slightly different way
(please read the description of the mixer above).
The digital connection works only with CD-ROM drives that has support
for it. Note that some CD-ROM drives having this digital output
connector use a different signal level than the one required by SB
Live. This means that the digital connection doesn't work with all CD-
ROM drives (no sound). If you have problems with the digital connection
you should use the analog one. When using the the digital CD input you
may need to adjust the 'digcd' volumes using ossxmix (or ossmix).
It should be noted that SB Live works internally at 48 kHz. This means
that all S/PDIF input signals are automatically sample rate converted
to 48 kHz. If you record from a 44.1 kHz (CD-ROM) and save the result
to a 44.1 kHz file the signal will be sample rate converted twice.
First from the 44.1 kHz input to internal 48 kHz and then back to 44.1
kHz. While the sample rate converter of SB Live is very precise this
will cause some change. This should not be any problem when doing audio
recordings but it may cause unwanted results when transferring digital
data (such as AC3/DTS) using the S/PDIF the interface.
o sblive_digital_din=<0|1> - This option is to enable/disable the
"digital DIN" output of SB Live. By default the digital DIN
interface is disabled which enables the center/LFE analog output
(uses the same combo jack). By setting the sblive_digital_din option
to 0 you can enable the analog Center/LFE output feature. When
digital DIN is disabled you can still get S/PDIF (or AC3) output
from the digital (optical/coax) outputs of the optional livedrive
unit. Default: 0=analog output.
o audigy_digital_din=<0|1> - same as "sblive_digital_din" option
except for the Audigy soundcards. Default: 1=digital output.
o sblive_devices=<1..32> - Number of audio devices to be configured.
o SB Live! devices will not work in Sparc systems due to PCI
addressing limitations. Only Audigy/Audigy2 models work under Sparc.
o EMU Wavetable MIDI synthesizer is not supported
o AC3 passthrough only supported on Audigy/Audigy but not on SB Live!
/etc/oss4/conf/oss_sblive.conf Device configuration file
27 September 2011 oss_sblive(7)