Re: [fluid-dev] Status of synth.audio-channels and synth.audio-groups

[Lorenzo Sutton]

Hi Tom,

On 26/04/2016 17:03, Tom M. wrote:
> Hi Lorenzo,
>
> > Thanks for the pointers. From what you write, therefore, it is not
> > currently possible to route each midi channel to an independent audio
> > output with jack. Right?
>
> It is possible. Have you tried smth like:
>
> fluidsynth -o audio.jack.multi=no -o synth.audio-channels=16 -o synth.audio-
> groups=16  "someSoundfont.sf2"
>
> you should get 16 stereo output channels. and since there 16 midi channels,
> each midi channel will get its own stereo channel. or which behaviour do you
> experience?

Indeed that's the behaviour I expect. Do I have to specify 16? I tested 
with lower numebrs (e.g. 4, 6)... Maybe that is the problem?

> NOTE: actually audio.jack.multi should be set to "yes". however this option
> currently has inverse logic. thats a bug. leaving it at "no" should give you
> multiple channels though.

Yes I read about this and was using the 'no' option.

> Another bug related to that: whenever specify N output channels while N>1
> there wont be any effects applied, see this ticket
>
> https://sourceforge.net/p/fluidsynth/tickets/137/
>
>
> I've attached two patches that should fix/workaround those two issues.

Good to know. And thanks for the patches.

> Tom
>
>
> Am Dienstag, 26. April 2016, 09:36:36 schrieb Lorenzo Sutton:
> > Hi Jean-Jacques,
> >
> > On 25/04/2016 14:02, jean-jacques.ceresa wrote:
> > > Hi,
> > > May be this will help.
> > > This link is a starting point of discussion.
> > >
> > > http://lists.nongnu.org/archive/html/fluid-dev/2015-04/msg00009.html
> > >
> > > 1)It gives functionnal behaviour of synt.audio-channels settings.
> > > 2)audio.jack.multi is discuted also (with a possible minor bug).
> > >
> > > 3) audio-groups and audio-channels number are used at mixer
> > > initialization time
> > > to define the maximum output buffer number like this.
> > >
> > >     output_buffer_count = max (audio-channels,audio-groups).
> > >
> > > May be synth.audio-groups is only useful when one want for the plugin
> > > effect unit ?.
> >
> > Thanks for the pointers. From what you write, therefore, it is not
> > currently possible to route each midi channel to an independent audio
> > output with jack. Right?
> >
> > The actual use cases I'm after are essentially 2:
> > 1. Record different instruments from a "general midi" soundfont (on
> > different midi channels) independently e.g. in Ardour on a track per
> > instrument.
> > 2. Record drums from a drum soundfont independently to their own track
> > in the DAW (Ardour). In that case I woul be sequencing each drum on its
> > own channel.
> >
> > I understand use case 2 is rather corner, but 1. is probably not that
> > exotic.
> >
> > Lorenzo.
> >
> > > jjc.
> > >
> > > Le 24/04/2016 03:11, Lorenzo Sutton a écrit :
> > > > Hi all,
> > > >
> > > > 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.
> > > >
> > > > Lorenzo
> > > >
> > > > _______________________________________________
> > > > fluid-dev mailing list
> > > > address@hidden
> > > > https://lists.nongnu.org/mailman/listinfo/fluid-dev
> > >
> > > _______________________________________________
> > > fluid-dev mailing list
> > > address@hidden
> > > https://lists.nongnu.org/mailman/listinfo/fluid-dev
> >
> > _______________________________________________
> > fluid-dev mailing list
> > address@hidden
> > https://lists.nongnu.org/mailman/listinfo/fluid-dev
> >
> >
> > _______________________________________________
> > fluid-dev mailing list
> > address@hidden
> > https://lists.nongnu.org/mailman/listinfo/fluid-dev