[Ardour-Users] Ardour with multiple cheap (USB) audio interfaces.

Robin Gareus robin at gareus.org
Fri Jan 10 17:57:02 PST 2014

On 01/11/2014 02:25 AM, ChaosEsque Team wrote:
> Hi, I'm really interested in helping people who want to use Ardour
> with multiple cheap (USB) audio interfaces. It doesn't seem very easy
> right now to do this sort of thing - in fact, I'm not even clear if
> it is possible 

It is possible, but you're quite right that it's not very accessible,
mainly  because there is no GUI to set this up. You'll need to resort to
a few terminal commands.

Ardour uses JACK, so the goal is go add an additional soundcard to jack.
There are various options to do this, most of which are described at

> and I'd appreciate some guidance because I think
> this is really important group of people: folks that can't afford
> multichannel interfaces and lots of amps, the sort of people who
> might really be attracted to a tool like Ardour.

Fair point. As explained on the linked page, it is not ideal to use
multiple un-synced soundcards, but it can be good enough for many cases.
The easiest way to do so on GNU/Linux is to to use alsa_in/out:

First start jackd as usual with one soundcard - and then add the others
as needed.  This is as easy as opening a terminal and running
   alsa_in -d hw:1
This adds the 1st soundcard (hw:1) inputs to an already running jackd.

Instead of numeric IDs you can also use the name of the soundcard.
Device and their names can be listed with 'aplay -l'. For example

card 3: UA25 [UA-25], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

in this case 'alsa_in -d hw:3' is equivalent to 'alsa_in -d hw:UA-25'

To add outputs use the sister of alsa_in: 'alsa_out -d hw:DEVICE'

Hope that helps,

PS. there are ways to automate this process as well as auto-detect,
auto-launch. Yet, this is mostly undocumented territory and requires a
bit of scripting which builds upon above concept. More later if you're

More information about the Ardour-Users mailing list