ALSA/Audigy Multichannel Setup

I have an Audigy 1 card that I wanted to be able to use the surround outs as a separate output on my board. After messing with my .asoundrc file, here's the config that worked.

pcm.rd0 {
 type plug
 slave {
    pcm "front"
 }
}
ctl.rd0 {
 type hw
 card 0
}

pcm.rd1 {
 type plug
 slave {
       pcm "rear"
 }
}
ctl.rd1 {
 type hw
 card 0
}

I believe the "rear" and "front" keywords are unique to the Audigy emu10k1 driver, not every Alsa card driver will include them.

I also came very close using the Alsa dmix plugin, but the output from Rivendell was unusable.