Linux SB Audigy2 Support
http://www.linuxlogin.com/linux/emu10k2.php Linux SB Audigy2 Support
This page is for Audigy2 (emu10k2) chipset cards. They can do 24bit
192Khz with 106dB SNR. The Platinum ed adds a "Audigy2Drive", 5 1/4"
bay used to hook up digital in/out and also includes a IR remote. Look
at Creative Labs website for
more information. This newer and more advanced DSP (Digital Signal
Processor) has lots of neat features with the good support under Linux.
This how-to covers ALSA since at this time (05/03/2003) the OSS (emu10k1) driver doesn't seem to fully support Audigy2 cards.
My setup includes:
- SB Audigy2 Platinum (Audigy2Drive Digital Out)
- Logitech Z680 Dolby Digital 5.1 THX Speaker System
- Linux Kernel 2.6.0-gentoo-r1
- Alsa 1.0.0-rc2 (Kernel modules)
AC3 Passthrough
I have tested both Xine (Xine-libs 1.0.0-rc3a) and mplayer
version 1.0pre3-3.3.2 and found AC3 to work. AC3 worked using Coax out
on my Audigy2Drive. (5 1/4" Bay Connector) For Xine, you just need to
check the a52_pass_through on the Audio tab.
And for mplayer using the following command:
<?php
mplayer -ao alsa9 -ac hwac3 dvd://1
?>
Configuration Files
~/.xine/config
<?php
audio.a52_pass_through:1
audio.five_lfe_channel:1
?>
Mixer Channels
As of ALSA 0.9.7 the following matrix gives you an idea of what all
those mixer channels actually do on my Audigy2. Please noticed that the
AC97 Channels show up in Alsamixergui as "AC97", "AC97", and "AC97
Master." However, the first AC97 is actually AC97 Playback Volume. The
reason this is important is if you wanted to record from your TV card
that passes sound through line-in, you can do so without having it come
across the rest of the card. I record TV broadcasts for viewing later
without having to watch/listen to the live show. This way you can skip
commericals later and not have to shut down xmms! *grin*
Alsa 0.9.x
| Channel | Effect |
| AC97 Playback Volume | Output volume level for line-in (what you hear) |
| AC97 Master Playback Volume | Master output for all AC97 Channels (like input-gain) |
| AC97 Capture | Capture level for recording only apps |
Versions <= 0.9.8 have a problem with mixer channels doing what
you'd expect. For example, if you trun down PCM channel to 0%, you
would expect no sound from xmms. However, if you have Wave Center/Wave
Surround/etc turned up then sound is still played.
UPDATE:The developers have fixed the mixer controls in
1.0.0-rc2 so that PCM now controls PCM output for all channels. And
Master controls all output volume. They also change AC97 to Analog Mix
for my Audigy2. This does not apply to AC3 passthrough levels.
Alsa 1.0.0-rc2
| Channel | Effect |
| Analog Mix Playback Volume | Output volume level for line-in (what you hear) |
| Analog Mix Capture Volume | Capture level for recording only apps |
| Line Playback Volume | Once levels set for above, controls overall volume for input |
Last update: 2005-04-30 01:55
Author: Erkan Kaplan
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