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- From: sgi-faq@viz.tamu.edu (The SGI FAQ group)
- Newsgroups: comp.sys.sgi.misc,comp.answers,news.answers
- Subject: SGI audio Frequently Asked Questions (FAQ)
- Supersedes: <audio_993016817@viz.tamu.edu>
- Followup-To: comp.sys.sgi.misc
- Date: 6 Jul 2001 05:59:43 GMT
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- Reply-To: sgi-faq@viz.tamu.edu (The SGI FAQ group)
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- Xref: senator-bedfellow.mit.edu comp.sys.sgi.misc:57356 comp.answers:46101 news.answers:210653
-
- Archive-name: sgi/faq/audio
- Last-modified: Wed Oct 20 1:00:04 CDT 1999
- Posting-Frequency: Twice monthly
- URL: http://www-viz.tamu.edu/~sgi-faq/
-
- SGI audio Frequently Asked Questions (FAQ)
-
- This is one of the Silicon Graphics FAQ series, which consists of:
-
- SGI admin FAQ - IRIX system administration
- SGI apps FAQ - Applications and miscellaneous programming
- SGI audio FAQ - Audio applications and programming
- SGI diffs FAQ - Changes to the other FAQs since the last posting
- SGI graphics FAQ - Graphics and user environment customization
- SGI hardware FAQ - Hardware
- SGI impressario FAQ - IRIS Impressario
- SGI inventor FAQ - IRIS Inventor
- SGI misc FAQ - Introduction & miscellaneous information
- SGI movie FAQ - Movies
- SGI performer FAQ - IRIS Performer
- SGI pointer FAQ - Pointer to the other FAQs
- SGI security FAQ - IRIX security
-
- Read the misc FAQ for information about the FAQs themselves. Each FAQ is
- posted to comp.sys.sgi.misc and to the news.answers and comp.answers
- newsgroups (whose purpose is to store FAQs) twice per month. If you
- can't find one of the FAQs with your news program, you can get it from
-
- ftp://viz.tamu.edu/pub/sgi/faq/
- ftp://rtfm.mit.edu/pub/usenet/news.answers/sgi/faq/
-
- (rtfm.mit.edu is home to many other FAQs and informational documents,
- and is a good place to look if you can't find an answer here.) The FAQs
- are on the World Wide Web at
-
- http://www-viz.tamu.edu/~sgi-faq/
-
- If you can't use FTP or WWW, send mail to mail-server@rtfm.mit.edu with
- the word 'help' on a line by itself in the text, and it will send you a
- document describing how to get files from rtfm.mit.edu by mail. Send the
- command 'send usenet/news.answers/sgi/faq/misc' to get the SGI misc FAQ,
- and similarly for the other FAQs. Send the command 'send
- usenet/news.answers/internet-services/access-via-email' to get the
- "Accessing the Internet by E-Mail FAQ".
-
- You may distribute the SGI FAQs freely and we encourage you to do so.
- However, you must keep them intact, including headers and this notice,
- and you must not charge for or profit from them. Contact us for other
- arrangements. We can't be responsible for copies of the SGI FAQs at
- sites which we do not control, and copies published on paper or CD-ROM
- are certain to be out of date. The contents are accurate as far as we
- know, but the usual disclaimers apply. Send additions and changes to
- sgi-faq@viz.tamu.edu.
-
- Topics covered in this FAQ:
- ---------------------------
- -1- How do I program the Motorola 56000 DSP on the Indigo (R3K and
- R4K)?
- -2- How do I connect my stereo to my Ind{igo,igo2,y}?
- -3- How do I change the volume of the audio out the back of my
- machine?
- -4- Indigo2 speaker seems quieter than my Indigo. Am I imagining
- things?
- -5- I need to crank up the input gain on Indigo2 to use the
- microphone successfully. What's the scoop?
- -6- The glossy paper says that Indigo2 and Indy have 4-channel input
- and output. That sounds really cool. How do I use it?
- -7- Okay, so 4-channels of input and output is great, but I need
- more. Can I get more channels of audio for my machine?
- -8- Now that I have IRIX 5.2, I can't seem to find audio.h and
- libaudio.a in order to compile my audio code. What gives?
- -9- I like the boot tune, but it's just a bit too loud. How do I tone
- it down a bit?
- -10- How can I change the output speaker/headphone volume from a shell
- script?
- -11- What 3rd party audio solutions exist for Silicon Graphics
- machines?
- -12- I'd like to write my own audio programs. How do I get started?
- -13- How can I get the keyboard beep out line out/digital out on
- Indigo2?
- -14- How do I suppress the keyboard bell (which *does* come out the
- line out and digital output) on an Indy?
- -15- Why does /dev/audio not work on my Ind{y,igo2,igo}?
- -16- Where can I get a MOD player for SGI?
- -17- I need audio for my Onyx. What are the details?
- -18- Why does my floating point signal processing routine, when given
- certain inputs, run incredibly slowly and consume all of the CPU
- in _system_ or _interrupt_ time?
- -19- What are the audio features of SGI machines?
-
- ----------------------------------------------------------------------
-
- Subject: -1- How do I program the Motorola 56000 DSP on the Indigo
- (R3K and R4K)?
- Date: 20 Aug 1994 00:00:01 EST
-
- Short answer: You don't.
-
- Long answer: The DSP on the Indigo is used exclusively by the audio
- system: whenever you are using the audio, you are using the DSP.
-
- In order to insure that audio processes are serviced, access to the DSP
- is limited to the audio device driver which performs all functions on
- behalf of application programs.
-
- Moreover, any code developed for the DSP on the Indigo may not work on
- other systems since the DSP is not guaranteed to be present. For
- instance, Indigo2 and Indy do not have a DSP. Audio is supported by a
- combination of code running on the CPU and a audio ASIC chip. SGI
- supports the Audio Library software inter- face as opposed to any
- particular hardware implementation of the audio system.
-
- Lastly, any signal processing code developed on the host CPU benefits
- from speed increases of the CPU (and this code is easier to write as
- well).
-
- ------------------------------
-
- Subject: -2- How do I connect my stereo to my Ind{igo,igo2,y}?
- Date: 20 Aug 1994 00:00:01 EST
-
- The Line in and Line out levels have been designed to be directly
- connected to conventional stereo systems.
-
- One way to do it is to connect it up as if the computer was a tape
- recorder. Line out on the computer connects to Rec in on the stereo
- and Line in connects to Rec out.
-
- ------------------------------
-
- Subject: -3- How do I change the volume of the audio out the back of
- my machine?
- Date: 20 Aug 1994 00:00:01 EST
-
- The headphone and speaker volume is adjusted using apanel(1). The
- sliders under the 'Speaker' label control the output volume of the
- speaker and headphone. The line-level output voltage is not
- affected.
-
- ------------------------------
-
- Subject: -4- Indigo2 speaker seems quieter than my Indigo. Am I
- imagining things?
- Date: 20 Aug 1994 00:00:01 EST
-
- No, this is not a figment of the imagination. There are two factors
- at work that make the Indigo2 quieter than Indigo: 1) the speaker amp
- is less powerful on Indigo2; 2) the system fan on Indigo2 is louder
- than the Indigo fan. These two things lead to a quiet speaker that
- seems even quieter. See the release notes for more information.
-
- ------------------------------
-
- Subject: -5- I need to crank up the input gain on Indigo2 to use the
- microphone successfully. What's the scoop?
- Date: 20 Aug 1994 00:00:01 EST
-
- The Indigo2 and Indy both have less input gain than the Indigo and
- 4D/35. However, all have plenty of gain to operate the microphone.
- On the Indigo2 and Indy, you have to set the input gain to a larger
- nominal level.
-
- ------------------------------
-
- Subject: -6- The glossy paper says that Indigo2 and Indy have 4-
- channel input and output. That sounds really cool. How
- do I use it?
- Date: 20 Aug 1994 00:00:01 EST
-
- In order to enable 4-channel audio, you must choose "4-channel mode"
- from the 'Options' menu of apanel or make a call in your program to
- ALsetparams(3A). See the man page for ALsetparams(3A) for more infor-
- mation.
-
- Enabling the 4-channel mode will cause the electrical char-
- acteristics of your audio connections to change: the headphone jack
- will become a second line-level output (like the normal line-level
- output). The mic input will become a second line-level input *if* you
- have 'line' selected as your input source. If you have the input
- source set to 'mic', then the mic input will continue to behave as a
- microphone input.
-
- Lastly, when your machine is in 4-channel mode, the input and output
- sample rates will be locked together. Thus, changing the input or
- output rate in this mode will affect the output or input rate,
- respectively.
-
- You may also run 4-channel applications when the audio system in in
- 2-channel mode, and vice versa (2-channel applications work when the
- system is in 4-channel mode).
-
- ------------------------------
-
- Subject: -7- Okay, so 4-channels of input and output is great, but I
- need more. Can I get more channels of audio for my
- machine?
- Date: 20 Aug 1994 00:00:01 EST
-
- Sonic Solutions (San Raphael, CA) has announced that it is porting
- Sonic System to SGI platforms. See below.
-
- ------------------------------
-
- Subject: -8- Now that I have IRIX 5.2, I can't seem to find audio.h
- and libaudio.a in order to compile my audio code. What
- gives?
- Date: 8 Mar 1997 00:00:01 EST
-
- The #include file audio.h and the library libaudio.a became a part of
- the "Digital Media Developement Option" (dmdev) in IRIX 5.X. Dmdev
- contains more than just the audio development libraries, and it is
- available for an extra fee. If you are like many people and think
- this is a bogus situation, tell your salesperson.
-
- For IRIX 5.3 and later, the digital media libraries, including the
- audio development environment (audio.h and libaudio.a), are part of
- the IRIS Development Option (IDO). Thus, you need no additional
- products (i.e. DMDEV) to develop software which utilizes the built-in
- digital audio.
-
- ------------------------------
-
- Subject: -9- I like the boot tune, but it's just a bit too loud. How
- do I tone it down a bit?
- Date: 20 Aug 1994 00:00:01 EST
-
- The boot tune volume is controlled by the 'volume' variable used by
- the system PROM. The value for 'volume' can be set in the range
- [0-255], where lower numbers represent a lower boot tune volume. A
- 'volume' value of 0 disables the boot tune, viz. the tune is not
- played at all. The value of 'volume' can be set in the PROM monitor
- or using the nvram(1M) command.
-
- ------------------------------
-
- Subject: -10- How can I change the output speaker/headphone volume
- from a shell script?
- Date: 20 Aug 1994 00:00:01 EST
-
- You can use two methods to do this: 1) apanel -nodisplay or volume.c
- program (this program can be found in ~4Dgifts/examples/ libaudio
- directory).
-
- ------------------------------
-
- Subject: -11- What 3rd party audio solutions exist for Silicon
- Graphics machines?
- Date: Wed Sep 22 13:31:10 CDT 1999
-
- Doug Scott <dscott@sgi.com> maintains a list of "Audio Applications
- for Silicon Graphics Systems" which he posts to comp.sys.sgi.audio.
- A copy is at http://reality.sgi.com/dscott/audio.apps/.
-
- ------------------------------
-
- Subject: -12- I'd like to write my own audio programs. How do I get
- started?
- Date: 26 Aug 1995 00:00:01 EST
-
- First, you need the IRIS Development Option (IDO). With IDO
- you get the Digital Media Development software (libraries for
- audio, video, compression, MIDI, and movie development).
-
- There is audio example code in the ~4Dgifts/examples/dmedia/audio
- directory. There you will find code demonstrating the use of
- libaudio and libaudiofile. You will also find a number
- of examples showing the combination of audio and graphical user
- interface (Motif) widgets.
-
- In the dmedia/cd+dat directory are example programs showing the
- use of libcdaudio and libdataudio.
-
- In the off chance that you are using IRIX 5.2 and cannot upgrade
- to 5.3, read the information below.
-
- Audio Development on IRIX 5.2 systems:
-
- First, for 5.2 systems you need the Digital Media Development
- Option. From Michael Portuesi (portuesi@sgi.com):
-
- The Digital Media Development Option contains the Video, Audio, Audio
- File, MIDI, CD, DAT, Movie, and Compression Libraries for your
- digital media programming enjoyment.
-
- The part number for the Digital Media Development Option is
- SC4-DMDEV-2.0. If you would like to develop applications which
- manipulate QuickTime files, you must also order the companion
- product, QuickTime 1.0 Compressor Library, part number SC4-QTCL-1.0.
-
- In the United States, you can order these products by calling Silicon
- Graphics toll-free at 1-800-800-SGI1 (1-800-800-7441). If you live
- in a country other than the United States, contact your nearest
- Silicon Graphics office, or call one of these regional telephone
- numbers:
-
- Europe (41) 22-798.75.25 (Geneva, CH)
- North Pacific (81) 3-5420.71.10
- South Pacific (61) 2-879.95.00
- Latin America 1(415) 390.46.37
- Canada 1(416) 625-4747
-
- For audio, example code is contained in ~4Dgifts/examples/libaudio.
- This example code comes with the DMDEV option. (For IRIX 5.3, the
- digital media libraries are part of the IRIS Development Option
- (IDO).) Other code demonstrating the use of the CD and DAT audio
- libraries can be found in a 'tar' file at ftp.sgi.com:~ftp/sgi/dat.
-
- ------------------------------
-
- Subject: -13- How can I get the keyboard beep out line out/digital out
- on Indigo2?
- Date: 10 Dec 1994 00:00:01 EST
-
- You can't. The keyboard beep is created by a chip on the Indigo2
- motherboard and the signal is mixed into the analog audio signal
- before going to the speaker (but after then D/A converter).
-
- ------------------------------
-
- Subject: -14- How do I suppress the keyboard bell (which *does* come
- out the line out and digital output) on an Indy?
- Date: 10 Dec 1994 00:00:01 EST
-
- Turning the bell off:
-
- xset -b OR xset b off
-
- See the xset(1) man page for more details.
-
- ------------------------------
-
- Subject: -15- Why does /dev/audio not work on my Ind{y,igo2,igo}?
- Date: 26 Aug 1995 00:00:01 EST
-
- The /dev/audio interface was created for the older 4D/20 platform
- with 8-bit audio. The actual file /dev/audio remains on
- Ind{y,igo2,igo}.
-
- The sole interface to audio on recent SGI machines is the Audio
- Library and the underlying driver(s).
-
- The program 'playulaw' in the 'radio' package (ftp.cwi.nl) will play
- u-law data piped from standard input. Also, the radio binaries are
- available at http://www.ibd.nrc.ca/~sgi. (Thanks to Walter Roberson
- <roberson@ibd.nrc.ca> for this information.)
-
- ------------------------------
-
- Subject: -16- Where can I get a MOD player for SGI?
- Date: 15 Feb 1997 00:00:01 EST
-
- There is an older version of 'tracker' by Marc Espie that runs on SGI
- machines. It's called tracker-al and can be found at:
-
- ftp://viz.tamu.edu/pub/sgi/software/audio/tracker-al.tar.gz
-
- Also, Stefan Kanthak <kanthak@Plutonium.Informatik.RWTH-Aachen.DE>
- has written a MOD player called 'mikmod' that supports SGI systems. It
- can be found at http://www2.eng.cam.ac.uk/~93sam/mikmod/
-
- ------------------------------
-
- Subject: -17- I need audio for my Onyx. What are the details?
- Date: 26 Aug 1995 00:00:01 EST
-
- There are two options for audio in an Onyx:
- 1. Audio/Serial Option from Silicon Graphics
- 2. VigraSound board from Vigra
-
- 1. Audio/Serial Option
-
- From Bill Warner (wtw@sgi.com):
-
- IRIS Audio Library now runs on Onyx/Challenge with the Audio/Serial
- Option (ASO). The ASO is a HIO card that installs on
- an IO4 board in an Onyx or Challenge.
-
- Supported platforms:
- -------------------
-
- o IP19 Onyx, Challenge, and RealityStation systems, running IRIX 5.3
- o IP21 Power Onyx and Power Challenge systems, running IRIX 6.0.1
- o current Audio Library software supports at most one ASO or VigraSound
- board per host
-
- Software:
- --------
-
- o The ASO audio software is binary compatible with Indigo2, Indy, Indigo,
- 4D/35 audio, and VigraSound audio.
-
- Any SGI or 3rd party application which is linked with the IRIS Audio
- Library will be able to run on a system that supports the ASO.
-
- o Onyx/Challenge customers may install the standard IRIS sound
- and movie tools (e.g. Audio Control Panel, Soundeditor,
- Movieplayer) from the dmedia_eoe and dmedia_tools images which are
- bundled with IRIX 5.3 or IRIX 6.0.1.
-
- Hardware:
- --------
- o HIO card that installs on an IO4,
- 3-space connector panels that install on the I/O door.
-
- o identical audio features as Indigo2 and Indy audio
-
- o 6 high-performance serial ports, each up to 115.2kbps. Software
- selectable between RS-232 and RS-422 modes. Non-STREAMS,
- shared-memory-based software interface provided, as well as standard
- STREAMS interface.
-
- Sales and support:
- -----------------
- The Audio/Serial Option is purchased from SGI. It has a list price
- of $4995.
-
- 2. VigraSound
-
- From Scott Porter (sporter@sgi.com):
-
- VigraSound version 1.0 now available from Vigra.
-
- IRIS Audio Library software now runs on Onyx/Challenge with
- VigraSound VME audio board.
-
-
- Supported platforms:
- -------------------
-
- o IP19 Onyx and Challenge systems
- o must be running IRIX 5.2
- o current Audio Library software supports one VigraSound board per
- host
-
-
- Software:
- --------
-
- o SGI and Vigra have developed an IRIS Audio Library driver module
- and microcode for Vigra's VigraSound (formerly "MMI-110") audio
- board.
-
- o The VigraSound software is binary compatible with Indigo2, Indy,
- Indigo, 4D/35 audio.
-
- Any SGI or 3rd party application which is linked with the IRIS
- Audio Library will be able to run on an IP19 system after the
- VigraSound board and vigrasound software module are installed.
-
- o Collaborative applications like InPerson, MediaMail, and the
- bundled IRIS media tools will now run with audio on an Onyx (no
- need to recompile or relink).
-
- o Onyx/Challenge customers may install the standard IRIS sound
- and movie tools (e.g. Audio Control Panel, Soundeditor,
- Movieplayer) from the dmedia_eoe and dmedia_tools images which are
- bundled with IRIX 5.2.
-
- o IP19 Onyx/Challenge developers may install the IRIS Audio Library
- from the dmedia_dev image which is included in the IRIS Media
- Libraries 2.0 software option product, along with the IRIS Media
- Libraries Programming Guide.
-
-
- Hardware:
- --------
-
- o 6U VME VigraSound audio board developed by Vigra (a division of
- VisiCom Laboratories, Inc.)
-
- o same feature set as the Indigo/4D35 stereo audio subsystem
-
- o inputs:
- stereo line-level,
- mono microphone (input level controlled through s/w),
- stereo AES/EBU digital port
-
- o outputs:
- stereo line-level,
- stereo headphone (output level controlled through s/w),
- stereo AES/EBU digital port
-
- o independent input and output sample rates
-
- o input sample rates: 8, 11.025, 16, 22.05, 32, 44.1, 48 kHz
- (rate may also be slaved to AES digital input rate)
-
- o output sample rates: 8, 11.025, 16, 22.05, 32, 44.1, 48 kHz
- (rate may also be slaved to AES digital input rate)
-
-
- Sales and support:
- -----------------
-
- o SGI customers purchase the VigraSound hardware/software package
- (including a CD which contains the vigrasound eoe s/w module)
- directly from Vigra, Inc.
-
- o List price for the VigraSound 1.0 hardware/software package:
- $3995
-
- o Vigra contacts for the VigraSound audio product:
-
- Julie Wix Product Manager (sales contact)
- Rusty Wise VP, Sales and Marketing
- Tim Elsmore Technical Director
-
- Vigra phone (619) 597-7080
- Vigra fax (619) 597-7094
-
- Vigra is a division of VisiCom Laboratories, Inc
-
- o Customers obtain all other software (IRIX 5.2, IDO 5.2, IRIS
- Media Libraries 2.0, etc) from SGI.
-
- o Vigra provides front-line support for customer issues related to
- the VigraSound audio product (hardware and software) on IP19
- Onyx/Challenge:
-
- Vigra Customer Support Group
- 6044A Cornerstone Court
- San Diego, CA 92121-4703
-
- email: techsup@vigra.com
-
- ------------------------------
-
- Subject: -18- Why does my floating point signal processing routine,
- when given certain inputs, run incredibly slowly and
- consume all of the CPU in _system_ or _interrupt_ time?
- Date: 03 Sep 1995 00:00:01 EST
-
- You may be experiencing an undesirable "floating point underflow"
- behavior of the floating point unit on R3k's and beyond. You'll need
- to add a workaround to your code and, on some machines, install a
- patch as well. A thorough writeup by Chris Pirazzi of SGI
- <cpirazzi@cp.esd.sgi.com> is at
- ftp://viz.tamu.edu/pub/sgi/software/programming/fp-underflow.
-
- ------------------------------
-
- Subject: -19- What are the audio features of SGI machines?
- Date: 26 Aug 1995 00:00:01 EST
-
- Indigo (R3000 and R4000):
- - Stereo analog input (line input or mic (mono) input)
- - Stereo analog output (simultaneous speaker/headphone & line out)
- - Serial digital input (supports AES and S/PDIF encoding)
- - Serial digital output (supports AES and S/PDIF encoding)
- - Independent input and output sample rates including:
- 8, 11.025, 16, 22.04, 32, 44.1, and 48.0 kHz
- - 3.5 mm connectors
- - microphone (mono) included
- - mono speaker
-
- Indigo2 & Indy & Audio/Serial Option:
- - Stereo analog input (line input or mic input)
- - Stereo analog output (simultaneous speaker/headphone & line out)
- - Stereo microphone support
- - 4-channel analog input and output using mic connector as second input
- pair and headphone connector as second output pair
- - Serial digital input (supports AES and S/PDIF encoding)
- - Serial digital output (supports AES and S/PDIF encoding)
- - Independent input and output sample rates including:
- 8, 11.025, 16, 22.04, 32, 44.1, and 48.0 kHz
- - 3.5 mm connectors
- - microphone (mono) included
- - mono speaker
-
- ------------------------------
-
- End of sgi/faq/audio Digest
- ******************************
- --
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