[PlanetCCRMA] Confusing Sound Issues in Fedora Core 3

[Fernando Lopez-Lezcano]

On Mon, 2005-03-14 at 14:07, Bradley S. Campbell wrote:
> Hi everyone,
> 
> I feel like I'm the same boat as Pierre with all this sound stuff in 
> FC3.  I do hear sounds in FC3 on startup (i.e. system sounds).  If I use 
> the libALSA output plugin in XMMS, I can use XMMS to play sounds, but I 
> can no longer hear system sounds -- I may be mistaken, but I thought the 
> whole purpose of ALSA was to be able to stream sounds from many 
> different concurrent applications through one output stream.

Not really. It's more simple than that. ALSA provides an interface to
soundcards. What you are talking about is a sound server, and
regretfully there's no standard there yet. KDE uses arts (I think) and
Gnome uses esd. None of them are in the same class as Jack, which is
meant to be low latency and can communicate apps together. 

Some cards have hardware support for multiple input streams and on those
ALSA should be able to do what you want. 

There's also a plugin in ALSA to do mixing for soundcards that don't
have hardware support for multiple streamsm, and it is called "dmix", I
have not really used it so I can't comment. 

> This sort 
> of leads me to my next point -- I've spent the better part of weekend 
> modifying everything from /etc/modprobe.conf  and ~/.asoundrc files (as 
> well as many others I probably can't remember right now) from all sorts 
> of tutorials I've found on the internet, and none really seems to be 
> well written enough to help me /understand/ what I'm doing -- just 
> things like "add this crazy incantation with a bunch of flags to some 
> file -- that should work" -- unfortunately, this hasn't produced much in 
> the way of results for me.  I know this sounds like me complaining (I'm 
> really not -- just frustrated), but it's just really frustrating to have 
> all these amazing applications at your fingertips and not even be able 
> to use them because you haven't been able to track down some arcane 
> setting somewhere (and I realize how hard it is to troubleshoot 
> complicated problems via email -- and I really appreciate all the help 
> I've gotten thus far).  In particular, I'd really like to use amSynth to 
> create some sounds for a project I have coming up in a computers and 
> music class I'm taking.  Everyone seems to be way ahead of me in knowing 
> what specific files and things to look for when troubleshooting these 
> types of things -- if someone would be willing to help me out or at 
> least point me in the direction of something I could read that could at 
> least let me integrate the many various things I've seen about getting 
> alsa, jack, midi events and their interplay between soundcards and the 
> kernel in general, it'd be greatly appreciated.  If someone would be 
> willing to help me troubleshoot, I'd gladly supply the contents of any 
> configuration file, system specs, etc. that you would need.

Most of the "interesting" applications for audio can communicate with
the Jack (stands for Jack Audio Connection Kit) audio server - but that
server will not, for example, play system beeps :-)

The usual (easy) way of starting Jack is to use the Qjackctl graphical
front end. Go to setup to see the options (and "man jack" to see what
they mean. The connections tab has Jack and MIDI patchbays. 

There's a lot to learn to be able to use a Linux system for audio, so
don't feel too frustrated. Sometimes it can be an excersice in patience.
_I_ get frustrated every once in a while, but well, that's the state of
things...

Good luck...
-- Fernando