Sound Blaster Audigy 2 + Debian 3.1 Sarge + ALSA

The Audigy 2 is touted as a soundcard with hidden goodies like a programmable DSP and 8 output channels, as well as 4.0 and 5.1 surround. I am trying to get 6 to 8 individual channels working. If only it was so simple...

I am using Debian Sarge with kernel-image-2.6.11-1-k7.

Apparently, the right device isn't showing up, so that probably means that I don't have the right version of ALSA. It looks like you need 1.0.9, or to apply the patch. Here's where I found that out: http://music.columbia.edu/pipermail/linux-audio-user/2005-January/020025.html

Here's my output:

root@winky:~ > cat /proc/asound/devices 
  4: [0- 0]: hardware dependent
  9: [0- 1]: raw midi
  8: [0- 0]: raw midi
 18: [0- 2]: digital audio playback
 26: [0- 2]: digital audio capture
 25: [0- 1]: digital audio capture
 16: [0- 0]: digital audio playback
 24: [0- 0]: digital audio capture
  0: [0- 0]: ctl
 33:       : timer
	 

Ah yes! Glorious Debian to the rescue, saving me hours of painful patching and compiling! I needed to get 1.0.9 version of source for the ALSA kernel modules, that version has the necessary patch for emu10k1 multi-channel. This seems to have done the trick:

apt-get install -t unstable alsa-source
module-assistant update
module-assistant install alsa

Look, now there's all sorts of new devices:

root@winky:~ > cat /proc/asound/devices
  4: [0- 0]: hardware dependent
  9: [0- 1]: raw midi
  8: [0- 0]: raw midi
 20: [0- 4]: digital audio playback
 28: [0- 4]: digital audio capture
 19: [0- 3]: digital audio playback
 18: [0- 2]: digital audio playback
 26: [0- 2]: digital audio capture
 25: [0- 1]: digital audio capture
 16: [0- 0]: digital audio playback
 24: [0- 0]: digital audio capture
  0: [0- 0]: ctl
 33:       : timer
	 

Jack

To install jack: apt-get install jackd qjackctl

So now that I got the right devices showing up, I set up jack to manage them. Unfortunately, they are not just straightforward channel 1 thru channel 8. By default, there was a strange mapping with two channels going to one speaker, and channels one and two showing up three times. I changed this with qjackctl

Mixer Notes

This are the apparent classifications of the various elements in the mixer (alsamixer, gamix, etc.)

• PCM Front, PCM Center, PCM LFE, and PCM Surround are used only for 5.1 playback.
• Front, Surround, Center, LFE control volume of stereo inputs mapped to the channels This is not multi-channel! Its just stereo mapped to numerous speakers.

So... I finally got 6 distinct, functional channels. Here's how they are mapped to Jack and the ALSA mixer:

1. Channel 1/Front (left)
2. Channel 2/Front (right)
3. Channel 3/PCM Surround (left)
4. Channel 4/PCM Surround (right)
5. Channel 1 ?
6. Channel 2 ?
7. Channel 5/PCM Center
8. Channel 6/PCM LFE
9. Channel 1/PCM Front (left)
10. Channel 2/PCM Front (right)

Links

Audigy Mixer Controls

A wiki discussion on the ALSA mixer controls. Good survey, not very in depth.

The devices you need to have

This is a quick way to test whether you have a new enough version of the driver.

$Id $