Downmixing ALSA asound.conf to Mono


i am trying to overwrite the default-Alsa settings in the asound.conf like this:

pcm.!default monocard

  slave.pcm "hw:0"
  slave.channels 2
  type route
  ttable {
    # Copy both input channels to output channel 0 (Left).
    0.0 1
    1.0 1
    # Send nothing to output channel 1 (Right).
    0.1 0
    1.1 0

If i route the sound to the device monocard, the sound comes just on the left channel. But i find no way to overwrite the default device. Any ideas?


I forgot to tell, that i use Pulseaudio over Alsa. But it seems, dass Pulseaudio ignores Alsa.

PulseAudio is a frontend/wrapper for ALSA which aims to automate some settings. But since you want to apply settings explicitly, I suggest to use ALSA only. Then I might be also able to help when still required, since I tackle by times with ALSA settings, but never used PulseAudio :wink:.