[linux-audio-user] connecting soundcards using JACK

[Nathan Callahan]

On 08/11/2004, at 3:37 AM, Jeroen Wijnhout wrote:

> Hi all,
>
> Would it be possible to connect my IMic USB soundcard capture port to 
> the
> onboard AC97 soundcard using JACK? I'm able to connect ports of a 
> single
> soundcard to each other, however I would like to be able to listen via 
> the
> onboard card what I'm recording on the external USB soundcard.
>
> It seems that I have to start the JACK daemon in such a way that it 
> can talk
> to both soundcards at the same time.

It's not possible to start jackd on more than one soundcard.  You can, 
however use ecasound's jack output to kind of simulate it.

Start jackd on the AC97 card, then issue the command:

ecasound -B:rtlowlatency -f:s16,2,44100 -z:nomultitrack -z:nointbuf 
-o:jack -i:alsa,<iMic ALSA device>

This is based on a script that I had set up to do something similar.  I 
can't quite remember why all of those options are there, so they might 
not be necessary.

This may be a little unstable, but it's much better than trying to keep 
the soundcards synced properly.  No guarantees, YMMV.

Regards,
	Nathan Callahan