[geeks] Ubuntu sound question - esd w/alsa...

[Charles Shannon Hendrix]

Wed, 13 Sep 2006 @ 10:41 -0400, Joshua Boyd said:

> > For example, I'm pretty sure FreeBSD's sound devices all mimic Linux OSS
> > interfaces.  Let's put it this way, I never had to rewrite software for
> > FreeBSD when using the Live! pcm driver.  I suppose it could have only
> > been that one driver though.

Wow, that was an awful lot of untrimmed citation...

> OSS compatibility doesn't preclude having a decent driver model.  

Depends.  If you offer nothing but the OSS API, then it certainly does
keep you from having a good driver model.

The OSS API limits the feature set and how much can be done with sound
software and hardware.

Therefore a good driver will need to provide the OSS API and also an
extra set covering the other bits that are needed.

That is what ALSA does.

> For
> instance, ALSA offers compatibility to applications expecting OSS.  OK,
> so their compatibility can potentially be problematic for a lot of
> people.  

Seems to work for me except that it seems to overdrive some of the input
circuitry.  It's as if it turns up some preamp circuit too much.

Not hard to fix, but it is annoying to have to twiddle the mixer to run
an OSS application and then fix it back for an ALSA application.

Their OSS layer also really hates "unclean" sound samples for whatever
reason.

> I don't know what the issue is exactly, other than ALSA configuration
> is in general confusing if you have to touch it because it wasn't
> correct to start with.

Just an example: if I use xmms (which uses OSS API) to play mp3 files, I
have to adjust the mixer to bring input preamps down or sound is
distorted.  Then to play with something else I have to turn them back
up.  

The OSS and API mixer levels are not equalized.  Not sure why.


-- 
shannon "AT" widomaker.com -- [javalin: an unwieldy programming weapon used
to stab a software project through the heart until dead]