[PlanetCCRMA] Re: [Agnula-Users] Re: [Agnula-Developers] Re: [PlanetCCRMA] default .asoundrc file?

Fernando Pablo Lopez-Lezcano nando@ccrma.Stanford.EDU
Thu Jan 29 18:37:02 2004


> > > Is it really necessary to have one? So far I have never needed one. What
> > > would it provide that the default settings don't? I know that, for
> > > example, you can create stereo "devices" over a multichannel card but
> > > those are specialized setups, I would say. 
> > 
> > The only commonly-request  setup that  comes to my  mind is  the  dmix
> > virtual device - although you can obtain the same effect with jack.
> > 
> > Aside from this, what  I had in  mind was simply a complete  .asoundrc
> > with descriptive  comments  for  each  entry.    Something that  could
> > probably live into the documentation, probably.
> > 
> > In any case,  I'm interested and open  to  suggestions on what  a good
> > .asoundrc file  could be - but nothing  more than that, i.e.   in this
> > moment   we  don't  have  the  manpower   to study   all  the possible
> > combinations  .asoundrc  directives can  take and  come   out  with an
> > all-encompassing solution (supposing there is one).
>
>    OK, so if .asoundrc is useless, then why does every Alsa Sound Card
> matrix page tell you to do something like the following?
> 
> pcm.hdsp {
>    type hw
>    card 0
> }
> 
> ctl.hdsp {
>    type hw
>    card 0
> }

I have no idea why they tell you this. It is, I think, asoundrc
mythology :-) AFAIK this only creates a device named "hdsp" that does
the same thing as "hw:0"... 

Asoundrc can be very useful but it is not easily usable (at this point)
by mere mortals :-)

> My system doesn't seem to care if these exist or not. I can change the
> name of them to pcm.mark and it doesn't make any difference as far as I
> can tell. Some programs seem to allow me to talk to the name hdsp or mark,
> but some don't. 

I guess this would depend on whether the programmer allows you to
specify the name of a device explicitly. If not, then you are probably
stuck with using only the "hardware devices" or the standard plugin
interface. 

> I think a standard .asoundrc file could say why we do this
> in a comment if it wanted to.
> 
> In the case of my RME cards it appears a lot of Alsa programs don't query
> the card to find out it requires a period of 2, so the programs don't work.

Yes, not all programmers using ALSA take the trouble to properly query
for acceptable parameters. Too many, for example, think the world is
stereo only so that cards that need, let's say, 10 channels to run,
can't (ie: ice1712 based cards). 

> If I tell the program to talk to plughw:1,0 then the plughw plugin does
> a format conversion and allows the program to work. Maybe there's a better
> way to do this in .asoundrc? I haven't tried, mostly because I don't want
> to spend time scouring the web looking for clues.

-- Fernando