Chris Jones wrote: > I am trying to set up a USB sound bar on someone else's laptop running > ubuntu 10.10 with a gnome desktop.
what is this sound bar? something to eat :-)? > > Since it did not work out of the box, I thought I'd first enhance my > non-existent skills in this area by first practicising on my machine > with debian ‘lenny’ and no DE environment. > > I discovered rather quickly that what goes on behind the scenes is that > said sound bar is (emulates?) an additional sound card. usb sound devices _are_ additional sound cards (actually anything with a supported soundchip in linux would be a card) > > As a result, I have to direct each program that produces some form or > other of sound output to use the second audio device rather than the > default builtin sound card. not necessary if you configure the second one to be default ;-) > > I am able to get ‘mplayer’ to do this but I have no idea how I could > convince the flash plugin behind my web browser to do this, for > instance. > > Is there any way I can make the sound bar the system's default and be > done with it? you can read ALSA docs - they are weired but very good. I usually do few steps to setup a card. You have two options - to setup system wide or user specific > > While testing, I tried redirection when launching programs from the bash > prompt -- i.e. adding ‘/dev/dsp > /dev/dsp1’ -- with unsatisfactory > results: below par sound quality, loud cracks, the speakers go silent > for brief periods of time, etc. dsp is OSS (not ALSA) and it works only with additional modules (loaded and configured) > > I do not have access to the other laptop right now, but I would assume > gnome has some sort of GUI that lets you specify your default device > ‘system-wide’? check if there is pulse audio installed and running - this might be what you are looking for (there is something pactrl or alike or gui for this - I'm not using it but it's the future, so possibly you can use it) > > Another thing I noticed is that the volume button on the sound bar does > not work: I have to start alsamixer to control the volume, which is not > optimal. > > Does this mean that I am using a default generic audio USB driver for > this device and that I should look for something a bit more specific > that might support additional hardware features? I would say this was the configuration for the default card (built in) > > While I am at it I thought I might as well learn how these things work > and stop guessing :-) then start reading at http://www.alsa-project.org/main/index.php/Documentation > > Is there a reliable up-to-date document that you would recommend > reading? > > Thanks, > > cj > > P.S. I refrained from posting the 3 pages output by ‘lsusb -vs’. Not > sure if that would help at this point. > thanks, but it would help though to mention what kind of chip your usb card has (or vendor + model) I usually setup my notebook following way *) Add the user to the audio(+video) group *) create a file /etc/modprobe.d/sound with following ## ALSA portion alias char-major-116 snd alias snd-card-0 snd-hda-intel alias snd-card-1 snd-usb-audio ## module options should go here #options snd-hda-intel index=0 model=dell-m6,ref,auto #options snd-hda-intel index=0 model=ref enable_msi=1 options snd-hda-intel index=0 model=ref #options snd-hda-intel index=0 model=hp-dv5 enable_msi=1 position_fix=1 options snd-usb-audio index=1 This way I have always the built in card configured as "0" which means first and the usb as second The options you'll find in the kernel version /Documentation *) For user specific configuration and experimenting with alsa you can use $HOME/.asoundrc example # from http://alsa.opensrc.org/index.php/Dmix pcm.headset { # playback only on frontpanel headset type route slave.pcm dmixer slave.channels 8 ttable.0.0 1 # headphones front L ttable.1.1 1 # headphones front R } pcm.speakers { # playback only on desktop speakers type route slave.pcm dmixer slave.channels 8 ttable.0.4 1 # speakers L ttable.1.5 1 # speakers R } regards -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/idj5nl$27...@dough.gmane.org
