[vox-tech] AC97 Sound Card

Ken Bloom vox-tech@lists.lugod.org
Mon, 8 Mar 2004 13:53:39 -0800


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On Mon, Mar 08, 2004 at 12:59:03PM -0800, Mark K. Kim wrote:
> Crappy sound system... someone needs to make /dev/dsp into a virtual
> device that lets multiple apps open it directly and mix sound internally.
>=20
> -Mark

ALSA can do this - or at least something like this. Your card supports
hardware mixing, it will use that, if not then you can use the dmix
plugin, by configuring /etc/asound.conf like this:


pcm.!default {
        type plug
        slave.pcm dmixer
}
                                                                       =20
pcm.dmixer {
        type dmix
        ipc_key 1024 # This must be a unique IPC key (see ipcs output)
        ipc_key_add_uid true # UID will be added to IPC key
        slave {
                pcm "hw:0"
                period_time 0
                period_size 1024 # Must be power of 2 for alsa-oss
                buffer_size 8192 # ditto
                rate 44100
        }
}

pcm.dsp0 pcm.default
ctl.mixer0 "hw:0"

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