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vmixctl(7)			  OSS Devices			    vmixctl(7)

       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.

       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 audi-
	  gyls driver of OSS.

       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 ac-
       tual 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 out-
	  put jack. If you have	analog center/LFE  (subwoofer)	speakers  con-
	  nected  then	you  need  to  turn off	the sblive_digital_din (or au-
	  digy_digital_din) option.

       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 con-
       trolled using ordinary mixer programs (such as  the  mixer  applet  in-
       cluded  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  in-
       put  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' vol-
       ume  control  slider  can  be  used  to adjust the signal strength. The
       'igain' control doesn't usually have any	effect but some	hardware revi-
       sions may use it	for controlling	the microphone recording level.

       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 (dig-
       ital output volumes are not affected). The 'pcm'	setting	controls  vol-
       umes 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" set-
	  ting selects how front/rear speakers are used	for PCM	playback (out-
	  puts	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"  sec-

       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 mo-
	  ment).  These	volumes	will return back to maximum every time the de-
	  vice is opened. However this can be disabled by setting the 'autore-
	  set'	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).

       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 play-

       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 cur-
	  rently playing.

       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	micro-
	      phone  input  or some other (unused) input. Use the ossxmix pro-
	      gram 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 sec-
	      tion or the AC97	mixer  section	this  affects  all  subsequent
	      recordings. Remember to raise the	volume prior doing any record-
	      ing. After that decrease the volumes again if necessary.

       You can use /dev/oss/oss_sblive0/ pcm0-pcm7 to play multiple audio pro-
       grams  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 be-
       tween  1	 and  32  for the number of channels you wish. You can also do
       this manually  by  editing  oss_sblive.conf  and	 inserting  sblive_de-
       vices=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  ca-
       ble  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 con-
       nector 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	inter-
	  face 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.  De-
	  fault: 0=analog output.

       o  audigy_digital_din=<0|1>  -  same as "sblive_digital_din" option ex-
	  cept 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  address-
	  ing 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!

       /usr/local/lib/oss/conf/oss_sblive.conf Device configuration file

       4Front Technologies

			       28 February 2021			    vmixctl(7)


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