Provided by: oss4-base_4.2-build2010-5ubuntu9.1_amd64 
NAME
oss_sblive - Creative Labs Sound Blaster Live/Audigy family driver.
DESCRIPTION
Open Sound System driver for Creative Labs Sound Blaster Live!, Audigy, Audigy2,
Audigy2-Value and sound cards.
The sblive driver supports:
• 8-48Khz Playback/Recording
• 8 or 16 bits
• SPDIF digital output and Input
• 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.
• Sound Blaster Live 5.1 card is used in some Dell machines but it's driven by the
emu10k1x driver.
• 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.
• 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 audigy_digital_din)
option.
• 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.
SBLIVE MIXER 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 ’cd' signals can be routed
to the master mixer by selecting that device as 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 inputs).
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:
• 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" section.
• "/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 shown).
• The equalizer section: This section controls the graphic equalizer for front
speakers only.
• 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 speakers.
SBLIVE RECORDING 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 playing.
To record audio that's playing on any of the SB Live channels:
• 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 currently playing.
• Type ossrecord -s<sampling rate> -b<bits/sample> -c<channels> test.wav
• 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).
Hint: Look at the VU meter panels of ossxmix. It's usually very easy to locate the noise
source by looking which input has some signal coming from it.
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 - /dev/dsp7.
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
CDROM CONNNECTIONS 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
connections.
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.
CONFIGURATION OPTIONS
• 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.
• audigy_digital_din=<0|1> - same as "sblive_digital_din" option except for the Audigy
soundcards. Default: 1=digital output.
• sblive_devices=<1..32> - Number of audio devices to be configured.
LIMITATION
• SB Live! devices will not work in Sparc systems due to PCI addressing limitations. Only
Audigy/Audigy2 models work under Sparc.
• EMU Wavetable MIDI synthesizer is not supported
• AC3 passthrough only supported on Audigy/Audigy but not on SB Live! devices.
FILES
/etc/oss4/conf/oss_sblive.conf Device configuration file
AUTHOR
4Front Technologies
17 January 2023 oss_sblive(7)