[linux-audio-dev] Re: avoiding signal invertion

[Nicola Larosa]

Andrew Gaydenko wrote:
> (Sorry for crossposting, it seems like Alsa-user list hasn't an answer)
> 
> I use ICE1724 ALSA driver for Terratec Aureon 7.1 Space card. I have noticed
> both default (line out) and plug:spdif devices'es outputs are inverted. Is there
> a way to add additional inversion and, as a result, to get "normal" output signal?

I have a Terratec Aureon USB 5.1 MKII, and have channel inversions too.
Here's the relevant snippet of my asound.conf:


# Terratec Aureon USB 5.1 MKII
# software mixed, multiple access in output only
pcm.dmix51 {
  type dmix
  ipc_key 12347
  slave {
    pcm "hw:2,0"
    channels 6
  }
}

pcm.aureon {
  type route
  slave.pcm "dmix51"
  slave.channels 6
  # Front Left
  ttable.0.0 0.7
  # Front Right
  ttable.1.1 0.7
  # Rear Left
  ttable.2.4 1.0
  # Rear Right
  ttable.3.5 1.0
  # Center
  ttable.4.2 1.0
  # LFE
  ttable.5.3 1.0
}

ctl.aureon {
  type hw
  card 2
}

The (Rear Left, Center) and the (Rear Right, LFE) pairs had to be swapped.
Also, I attenuated the Front Left and Front Right channels somewhat.

Hoe this helps.


-- 
Nicola Larosa - http://www.tekNico.net/

The answer isn't to make the command-and-control system harder to get
around, but to throw the system away. People do their best work not
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 -- Andy Lester, May 2006