Re: [LAU] jack and the merging of soundcards

From: Ede Wolf <listac@email-addr-hidden>
Date: Fri Nov 21 2014 - 00:12:09 EET

Thanks very much. I do know about zita-a2j any may end up using it for
recording smtpe through onboard audio, at least as an experiment, but
for standard audio I would like to avoid resampling whenever possible.
Also, maybe pure superstition, that a2j attached soundcard always feels
as just being second best, not treated equal.

However, if I may re-ask, as it has not been quite clear to me: While
alsa seems to be capable of handling two cards that way, would this also
work for jack or would jack refuse to fail for this trick?

Assuming, that jack sits on top of alsa, it should not care about
whatever witchcraft alsa brews beneath. But what do I know?

So is there a realistic chance that I would be presented with 52 inputs
instead of 26 as of now? Without using a2j?

For synchronizing both cards I'd use external wordclock.

Am 20.11.2014 um 22:33 schrieb Paul Davis:
>
>
> On Thu, Nov 20, 2014 at 3:56 PM, Ede Wolf <listac@email-addr-hidden
> <mailto:listac@email-addr-hidden>> wrote:
>
> I may perspectively run into a shortage of audio inputs and stumbled
> across a blog, that reads like it is possbile to "merge" two
> soundcards into one virtual, that eventually looks as a single one
> to alsa. However, that blog does not mention jack.
>
> Also, in an stone old ardour thread Paul Davis suggests to a similar
> problem: ", then you simply get 2 digifaces", but again, this may
> have been before the rise of jack.
>
>
> And now I am wondering wether this is a possible or even reliable
> way to trick jack into being able to to finally handle more than one
> soundcard, if presented by alsa as being a single one.
>
>
> this is a function of the ALSA driver for a given device, plus the
> capabilities of the device itself. We still don't know for sure whether
> ALSA can get all the cards started reliabily in < 1sample, but it seems
> as if it should.
>
> a more device independent way of doing this, but one that implies sample
> rate conversion going on, is to use zita-a2j to allow JACK to use more
> than one device. With current JACK1, this is even builtin to JACK itself
> and can be done from the command line.
>

_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@email-addr-hidden
http://lists.linuxaudio.org/listinfo/linux-audio-user
Received on Fri Nov 21 00:15:05 2014

This archive was generated by hypermail 2.1.8 : Fri Nov 21 2014 - 00:15:05 EET