[PlanetCCRMA] Re: [ecasound] delta-66 4 output card, accessing individual outputs??

Kai Vehmanen kvehmanen@eca.cx
Mon Nov 20 15:40:02 2006


On Mon, 20 Nov 2006, sara lidgey wrote:

> That didn't work, but thanks.  It seems strange that this is so 
> difficult.  When using ecasound in interactive mode I've been adding 
> outputs with this command: ao-add jack_alsa

demux/muxing of channels is one task that has been difficult to map to the 
command-line option syntax used in ecasound. You can do it, but the syntax 
is not always pretty (and gets very ugly if you have a _lot_ of channels).

> But how can I tell ecasound that the curently selected channel needs to 
> be connected to alsa_pcm:playback_3 or playback_4 ??  It always just

You can't from ecasound, but as Dave already mentioned, you can use any 
JACK routing utility like jack_connect, qjactctl, etc to make the 
connections. I actually was thinking of adding "jack-connect" and 
"jack-disconnect" commands to ecasound's interactive mode, but there 
didn't seem to be muc demand for them so those were left on the todo list.

So you add inputs and outputs with "ai-add jack" and "ao-jack", connect
them to the write chains and then use an external app (or the libjack 
API) to make the connections.

> defaults to connecting to playback_1 and playback_2 It should be noted 
> that i will eventually need all 4 channels going at once, so copying 
> from one channel and then muting won't work. Any help is appreciated.

If you want to do this without JACK:

ecasound -a:c1 -i foo1.wav \
 	 -a:c2 -i foo2.wav -erc:1,2 -eac:0,1 \
 	 -a:c3 -i foo3.wav -erc:1,3 -eac:0,1 \
 	 -a:c4 -i foo4.wav -erc:1,4 -eac:0,1 \
 	 -a:all -o alsa,plughw:0

But yeah, this is much nicer with JACK. :)

PS Cc'ed to PlanetCCRMA list as the question was also asked there...

  links, my public keys, etc at http://eca.cx/kv