24 Apr
2016
24 Apr
'16
2:22 p.m.
On Sun, Apr 24, 2016 at 03:13:42AM +0200, Lorenzo Sutton wrote:
Hi all,
I have also posted this on the fluid-dev list, but maybe there is some
wisdom on LAU about it as well :)
What is the current status of synth.audio-channels and
synth.audio-groups on Linux with jack?
By starting fluidsynth with something like:
fluidsynth -a jack -o synth.audio-channels=4 -o synth.audio-groups=4 \
-o audio.jack.multi=no
I do get 4 pairs of jack audio outputs.
However the behaviour isn't as expected at least according to this (very
old post):
https://lists.nongnu.org/archive/html/fluid-dev/2004-02/msg00027.html
Ideally is there a way to have each channel routed to a separate audio
output on jack these days? Any help appreciated.
'-o synth.audio-groups=4' fails: `fluid_settings_getint' returns 1
after `process_o_cmd_line_option' (also tested with a printf).
sh> fluidsynth -a jack -o synth.audio-groups=4 <<< settings 2>/dev/null \
| grep audio-groups
synth.audio-groups 1
Idem with "-o synth.audio-channels=4 -o synth.audio-groups=4",
but "-G 4" works:
sh> fluidsynth -a jack -G 4 <<< settings 2>/dev/null | grep audio-groups
synth.audio-groups 4
There is a comment in `src/fluidsynth.c:594':
/* The 'groups' setting is only relevant for LADSPA operation
* If not given, set number groups to number of audio channels, because
* they are the same (there is nothing between synth output and 'sound card')
*/
tested with:
sh> fluidsynth -a jack -L 4 <<< settings 2>/dev/null | grep audio-groups
synth.audio-groups 4
The follow example works (audio.jack.multi=no by default):
sh> fluidsynth -a jack -L 4
load /usr/share/sounds/sf2/FluidR3_GM.sf2
select 0 1 0 0
select 1 1 0 20
select 2 1 0 30
select 3 1 0 40