[PlanetCCRMA] aRts and alsa

[Fernando Pablo Lopez-Lezcano]

On Sun, 2004-08-15 at 16:17, Bruce Elliott wrote:
> Fernando Pablo Lopez-Lezcano wrote:
> > On Sun, 2004-08-15 at 08:45, Bruce Elliott wrote:
> > > <snip>
> > > My question is how does the native sound system of KDE (aRts, I assume) 
> > > interact with alsa and jack?  Should I be attempting to disable all of 
> > > the arts processing in favor of equivalent jack-aware processes?
> > > 
> > > <snip>
> > > Note: under the KDE Control Center | Sound & Multimedia | System 
> > > Notifications | Player Settings ... , I have *not* selected to use an 
> > > external player.  Should I set this to a jack-aware player, if jack is 
> > > running and I insist on hearing system notifications? 
> >
> > I don't think there is currently a solution to this problem. You can run
> > artsd or jack, but not both at the same time. Jack is designed for low
> > latency work and does not match very well the requirements for a general
> > purpose sound server (or rather, the expectations of what a general
> > purpose sound server should be). One solution would be a custom version
> > of artsd that would connect to jack as a sound server. But keep in mind
> > that for the kind of usage that Jack was designed for, a random sound
> > coming from a desktop operation and mixed with the mixdown of your audio
> > session would be unacceptable. 
>   
> Ah - I'd suspected as much.  Since I am not capable of writing a
> jack-compatible version of artsd, the issue of system noises entering
> audio processing is academic, although I would have hoped to 'unplug'
> artsd from jack when doing any real audio work.
> 
> Another approach I'm thinking about is to keep my current, very basic
> sound card, just to drive a pair of small 'PC speakers', after I get a
> higher-quality sound card for audio work.  Will I be able to have the
> artsd server work with the old card, sending system notifications to
> the PC speakers (and only to them), and to have jack run the new card,
> which will presumably be connected to a better playback system, for
> audio work?  I think I'm asking if alsa will let me associate each
> soundcard module with a different sound server (?).

Yes, that is definitely doable. Each card (if you configure both for
ALSA) will be independent of the other. It is very simple to start jack
pointing to either of them. I presume there is something similar for
artsd although I don't know where I would look for that configuration
bit. 

-- Fernando