[MPlayer-users] possible to send mono sound to just one speaker?

[Alexander Roalter]

Corey Hickey wrote:
> Alec Bennett wrote:
>> Thanks, that's progress. This line sends audio to only one of the speakers:
>>
>> -af pan=2:1
>>
>> The problem is, I can't figure out the pan filter. I can't really find any
>> docs on it. This is the closest I found:
>>
>> http://www.mplayerhq.hu/DOCS/HTML/en/advaudio.html
> 
> It's difficult, I admit. Do you have any suggestions as to how I could
> improve that document?
> 
> I think you might be getting confused by this particular example. In
> order to hear a mono file in one channel, you need to make two channels
> out of it, which seems rather strange at the outset.
> 
> 1. When mplayer outputs mono sound, the sound card (or the driver?)
> automatically sends the same channel to both speakers.
> 2. If mplayer outputs two channels instead, the channels are each played
> on their respective speakers.
> 3. If one of those channels contains silence, then you'll only hear a
> single speaker.
> 
> The pan example you gave above is actually short for pan=2:1:0. Missing
> parameters at the end default to 0. 2:1:0 means:
> - two output channels
> - the input channel is mixed 100% into the first (left) output channel
> - the input channel is mixed 0% into the second (right) output channel
> 
> As Alec Benett pointed out, 2:0:1 will play to the right speaker.
> 
> 
> Normally I would recommend using the channels filter instead of pan, for
> moving entire channels around without mixing, but in this case the
> syntax is actually longer:
> Left  speaker -- channels=2:1:0:0  (shortens to channels=2:1)
> Right speaker -- channels=2:1:0:1
Seeing this and having problem with my 5.1 setup: is it possible to mix
stereo signals (and mono, if there is some) into the front speakers,
wilst retaining a 6 channel output (therefore outputting 6 channels at
any time, but the rear and subwoofer+center silent? - or to send mono
signals to the center only...)

I'm having problem with my cmicpi chipset (to be found on a Terratec
Aureon 5.1), which (as I posted earlier) accepts 5.1 only on hw:0,1 (or
surround51), but outputs stereo on these channels on the rear speakers.

Now what I need would be some settings that work for both stereo and
surround, so that I would not have to choose a different output any time
I switch from stereo to surround playback...

cheers,
Alex