16 May
2008
16 May
'08
10:55 a.m.
Thanks for this Paul -- sorts that out nicely. So off to get a USB
soundcard for my laptop...
On Fri, 16 May 2008, Paul Davis wrote:
On Fri, 2008-05-16 at 11:20 +0100, J M Needham wrote:
Dear all,
Forgive me for not understanding this, but I've also heard conflicting
things on Alsa-User. On my PC (old H/W, Ubuntu Hardy Heron, SB audigy) I
can play sound through apps connected to jack and apps going direct to
Alsa at the same time. On my Debian sid box, I cannot have two appps
playing music at the same time. My Laptop, running Ubuntu GG (s/c HDA
intel) also behaves like this, whereas my friend's PC can do what my
Ubuntu HH box can do (new H/W, SB Audigy new(ish)), and
both have been able to do this since we both switched at Edgy Eft.
I don't understand this. Some people say that you cannot play sounds from
aps connected to Jack and apps not using jack at the same time, which
contradicts some of my experience and the experience of Joakim Hernberg
[below] so what's the difference? What files do I need to look at to find
the difference if there is any.
Is this a h/w or s/w issue? It's clearly possible, so why is there the
belief that it can't happen?
its both.
there is some audio hardware that supports "multi-open" directly in
hardware. i believe that your SB Audigy is one such device. this means
that multiple (typically somewhere from 8-32) applications can open it,
and the hardware mixes everything down to the outputs.
this type of h/w has become massively less common as Intel-HDA has
spread, since this "specification" leaves mixing like this to device
drivers and/or some OS audio infrastructure. mixing JACK & non-JACK
applications with audio interfaces that do not provide hardware
multi-open is essentially impossible (or just so kludgy that i don't
even want to discuss it).
--p