Pulseaudio right/left adjustment


I have two reproboxes (right and left). One of them doesn’t work, so I’d like to put both right and left stream in the other box. How do I do this in Opensuse 12.1/KDE?
There’s no option like that in KMix. Pavucontrol and Alsamixergui are better, they allow to increase/decrease volume per channel, however I cannot put both streams into a single headphone.
Can pulseaudio/ALSA do this, or shall I fill a wishlist bug? :slight_smile:

Thanks in advance!

What are reproboxes ? What do they provide wrt audio ?

It is possible with pulse audio to redirect sound in most fashions , although sometimes one may need to edit a configuration file.

Have you tried a google search for “pulse audio linux mix left right” ?

Thank you for your reply!

Two small boxes that stand on a table and play music. Connected through the standard 3,5 jack. Pretty much the same thing as headphones, but bigger and louder, so one don’t need to have anything on head. Reprobox might not be the best term, I’m sorry - English is not my mother tongue.

I dunno what is wrt audio and a quick Google and Wikipedia search didn’t help me, so I don’t know.

Of course. I know this is a silly argument, but in Windows this functionality is is available with a single click and I’ve always regarded this as similarly essential as volume control, so I believe it’s not neccessary to edit a configuration file. Especially when I need to adjust this several times a day (different headphones at work and at home…)

I did that. If I could Google it, I wouldn’t bother you :slight_smile: .

‘wrt’ is a unofficial but reasonably common English language abbreviation for the words ‘with respect to’

Hmmm … IMHO wrt MS-Windows, YMMV ('your mileage may vary) as I do NOT have such options on my MS_Windows setup. Its nice that you have. However I boot to MS-Windows typically once/every 3 or 4 months, so I also don’t need such settings (plus all 6 speakers in my 5.1 surround system work in GNU/Linux).

Hmmm … the thing is, I have a 5.1 system and I can’t test this for you without re-wiring cables on the back of my PC which I am very loathe to do. So that google approach is IMHO the way to go about this.

Install the application ‘pulse audio volume control’ (pavucontrol) and also setup a sink in pulse audio where you can mix channels. Using a google search I noted one possible command for such a sink might be:

load-module module-remap-sink sink_name=mono master=<the name of your main output sink> channels=4 channel_map=left,right,left,right master_channel_map=left,left,right,right

where the place to add that line might be in the file /etc/pulse/default.pa. Save the change, restart, test using pavucontrol to tune. Pulse audio may not like that at all. So if that does not work, remove it.

Note where it has you need to put a number … possibly something like

load-module module-remap-sink sink_name=mono-output master=0 channels=4 channel_map=left,right,left,right master_channel_map=left,left,right,right


load-module module-remap-sink sink_name=mono-output master=0 channels=2 channel_map=left,right,left,right master_channel_map=left,left,right,right

… again, remove if it does not work.

Another possible approach is to create a file /home/yourusername/.asoundrc and put inside:

pcm.pulse { type pulse }
ctl.pulse { type pulse }

save the change, restart your PC and test.

Now both of those were among the TOP hits in the google search. You state you tried the google search, but I can not tell if you attempted the suggestions that come out in the top hits.

Still, despite my having typed those possibilities, if it were me with this problem, once if I tried that and it did not work, I would remove that line and then I would go to the IRC chat channel on ‘freenode’ #pulseaudio and ask there how to do this.

Thank you very much for the detailed tips. I’d prefer to have some easy GUI and not to tinker with config files, though I accept that there might be no alternatives.
What I’m trying to find is clear from this screenshot:
SUSE Paste

I recommend you follow up on my post if you want to mix LEFT/RIGHT.

All the balance does is progressively mute one channel. It does NOT do mix left/right. It does not provide a ‘mixed’ type sound output which is what I understood you wanted. If that muting of one channel (per what MS-Windows does) is all you want, then that sort of balance control is available in pavucontrol. You need to look again then at pavucontrol.

Alternatively one can use alsamixer.

And its also in kmix, if you divorce kmix from pulse audio. To do that in KDE one needs to completely (completely !!! ) close kmix. Then send with root permissions something like:


and that will restore all of kmix’s settings. My recommendation is to not do that kmix approach.

But if you truely want to combine the LEFT/RIGHT then IMHO you need to go back and re-read my previous post.

It does mix left/right. Of course I can mute one channel in pavucontrol. But this actually does the mixing, it’s easy to verify, we just need any sound that uses the channels so that we can distinct between them - there are many songs/sounds like that.

Anyway, thank you very much for the detailed post!

hmmmmm … but you are willing to tinker with a gui. Whats the difference ? To tinker is to tinker. In my case I find command line edits EASIER than tinkering with a GUI. Trying to do screen prints to record gui tinkering is a real pain. But keeping track of text file changes is MUCH easier. One keeps a copy of the original file, and then can easily to a ‘diff’ or file comparison with the old vs the new file to see what one has changed. Typically with a GUI one has NOT a clue as to what they changed. Painful, and a time waster.

I think if you insist on looking for a GUI way then it will take you about 100x longer than it need to take. Its your time. But I would not waste one second insisting on a GUI way if there is a text edit way. IMHO its counter productive to adopt that approach in GNU/Linux. If one really likes a GUI approach (and I have many many MANY friends who like such) then IMHO paying for MacIntosh operating system is the way to go.

Did you try my suggestion to go to IRC freenode and ask on IRC channel #pulseaudio? Note I highlighted that in RED. I did so for a reason.

Anyway, another link from that same google search that I suggested and you say you conducted is this Modules – PulseAudio which suggests in the /etc/pulse/default.pa something like:

load-module module-remap-sink sink_name=fakestereo master=mono channels=2 master_channel_map=mono,mono channel_map=front-left,front-right

followed by a reset and test. I don’t have the setup to test that but you can try.