I have a question about a different way of doing this (soundcard mixer
dependent), and whether it is advantageous (or not) to use a soundcard's
built-in mixer, e.g. for direct monitoring at low-latency. If you have a
soundcard like the Terratec DMX6Fire or the M-Audio Delta66 you certainly
have the capability for this.
If you have a supported soundcard, from "alsa-tools" you use , e.g.
:/usr/bin/cspctl , /usr/bin/echomixer , /usr/bin/envy24control
, /usr/bin/hdspconf , /usr/bin/hdspmixer/ , /usr/bin/rmedigicontrol
, /usr/bin/sscape_ctl , /usr/bin/us428control ...
The alternative is to route via jack using qjackctl and/or take care of
mixing/monitoring in the DAW, e.g. ardour/rosegarden/qtractor.
What are the advantages of using the soundcard's digital mixer, esp.
envy24control & snd_ice1712
to route a single sound-source to an output for auditioning; or, if mixing
is needed, use the built-in digital mixer to directly mix the different
sound-sources? Note you have the option of digital-sync to a source that can
be mixed back through the digital mixer's SPDIF inputs as well (e.g.
reverb/room effects, madonna's-vocal-backing-track). And then route the
digital mix as the "headphone mix" back to the performer.
The main advantage I would predict (and can see) is slightly lower CPU
usage, which might matter on a laptop or older computer, but just seems like
a trivial amount of extra processing on today's fast 4 core machines. The
other advantage would be latency -- I can see no way that routing in and out
of soundcard(s) through jack would not add some latency -- the hardware
mixing option is marketed as "0 latency monitoring" for a reason.
However, in-practice, this practice is bedevilled by the mains or headphone
monitor outputs automatically being routed back from the digital mixer L/R
outputs, to their PCM0-3 outputs: at least when used via Jack/qjackctl . So
eventually, you end up hearing silence (since I usually would then digital
mix PCM4-7 leaving PCM0-3 unused or silent for this scenario). Any
suggestions, help or workarounds on the latter would be appreciated as well.
As I have yet to characterise what causes the automatic-routing-switchover,
(sometimes it can happen after a few hours, other times after a few minutes)
Niels
http://nielsmayer.com
_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@email-addr-hidden
http://lists.linuxaudio.org/listinfo/linux-audio-user
Received on Mon Jun 21 00:15:02 2010
This archive was generated by hypermail 2.1.8 : Mon Jun 21 2010 - 00:15:02 EEST