[nas] multiple dsp devices under linux?

[Paul Fox]

this isn't really about NAS, but since NAS interoperability
is my goal, and because there are a bunch of audio heads
here, i'll ask anyway:

irmp3 is a program which acts as a front-end to (usually)
mpg123, and lets you start/stop/control playback of files
and playlists.  since it can be controlled from things like
IR remote controls, one of the things it can do is give
confirmation beeps when it executes a command.  the irmp3
documentation contains the text:

    beep_device: <dsp device>
        The sound device through which to play the beep sounds.
        This cannot be the same device which mpg123 uses.  I 
	use /dev/dsp1.  Note that most sound drivers provide
	multiple dsp devices.

the last line is news to me.  in particular, i would like
very much to run the nas server on one audio device, and
have a second device available for use by non-nas-aware
applications.  is it really true that most linux sound
drivers have multiple entry points?  i'm using some ALSA and
some OSS drivers on my machines, so pointers as to how to
set this up on either basis would be most welcome...

paul
=---------------------
 paul fox, pgf at foxharp.boston.ma.us (arlington, ma, where it's 32.4 degrees)