[PlanetCCRMA] Using 2nd sound card for output

Fernando Lopez-Lezcano nando at ccrma.Stanford.EDU
Wed Nov 14 13:38:00 2007


On Wed, 2007-11-14 at 14:13 -0600, Fritz Whittington wrote:
> On or about 2007-11-13 13:04, Fernando Lopez-Lezcano pulled out a trusty 
> #2 pencil and scribbled:
> > On Tue, 2007-11-13 at 13:12 -0500, Roy Vestal wrote:
> >   
> >> I have FC7 with Ardour2, JACK, etc. working well. I have a Delta 1010 as 
> >> well as an on board AC'97. The output to the AC'97 is not showing in 
> >> JACK, but it works with "play wav.wav" for example. Is there a way to 
> >> get it so I can route the output of JACK apps (ardour2 for ex) to the AC'97?
> >>     
> >
> > Not really (unless you don't mind periodic clicks in the AC97 output).
> > If you want to use two cards they have to be in sync, that is, one has
> > to be a slave to the other. Otherwise the sampling rate clocks will be
> > slightly off and one card will output samples faster than the other and
> > eventually will have to skip a period so the other can catch up (ie: an
> > xrun or click will happen). 
> >
> > Does the AC97 onboard have an sp/dif output? If so you could perhaps
> > slave the 1010 to it. 
> >   
> I'd be really happy if I could just get the AC97 to work as the only 
> sound card, since it's the only thing I have in the laptop. 
> 
> Can someone point me to a HOW-TO (for dummies) to get midi out of the 
> AC97?  (If I install plain vanilla Fedora 7, the sound card works for 
> everything except midi.  If I install PlanetCCRMA's version of Fedora 7, 
> even that stops working!)

[I presume you meant to send to the list]

Midi is just a control protocol, you don't get sound out of it. Most
soundcards don't have a built-in synthesizer which responds to midi
commands, which is probably what you mean. Other exotic operating
systems use software synths to create sound when you send midi to the
"card". Linux is no different, you need to use a software synth to
render your sounds in most cases. Packages like ZynAddSubFX, Amsynth,
etc, etc. 

-- Fernando