LinuxMusicians

Zoom H4 USB Audio I/O

I need to get more adventerous with this device. Using only the mass storage transfer capability in Linux is missing out on the other stuff it can do.

Accordding to some sources: "The usb audio device also works fine, in alsa you get a /dev/dsp1, a new sound board with 2 inputs and 2 outputs".

I'm using the 2.6.18 Linux kernel. Looked at USB devices section, not really anything obvious there. Looked in ALSA USB section, NOTHING there at all. I'm using Debian stable BTW, mostly, with lots of self-compiled stuff.

I'll look about to see what I can find, and post back, but if anybody knows anything...

[edit]

I might add, I want to use this within JACK. At the same time as an M-Audio Delta 66.

I guess also, I better figure out which of my USB ports is definitely USB2.0 ;)

Ok, it does just work.
shows it there.

Next test, xmms, output to H4, yes.
Next test, setup JACK to work with H4, ie choose the H4 device. Yes.

But JACK simulataneously with H4 & Delta 66 ?

NO! BOOOO! WHY NOT? That's NBG!

James, jack cannot handle more than one device at a time. It will be possible with jack2 but not now. You can maybe set up some alsa conf file ($HOME/.asoundrc) to create a virtual device combining both but you will run into a synchronization problem. It is not really recommended but YMMV ...

Ah yes, I should know that really, just disappointing because I really would like to use them both at once in that way. I might attempt creating a virtual device as you suggest.

As I tend to the more experimental side of things, synchronisation drift might actually be a good thing (err yeah)!? I'll just have to try :)

James, something of interest for you :

http://trac.jackaudio.org/jack/wiki/Wal ... /AlsaInOut

I think this is in the jack source code (svn) but I have not explored the matter myself. You can try your luck ...

Hi Thorgal,

Cheers for the info there. I'll take a look soon. Firstly I want to look into the ALSA .asoundrc method, it's something I've never brushed up on yet, and could be useful.

Actually, what can be done with .asoundrc is quite interesting, for example, the only way (in my system atleast) for me to play two sounds together, is to mix the waveforms (ie in SND) or to start JACK, but ALSA does provide a mechanism for this (DMIX) (which I thought it would but never looked into) it's just not set up (((????))) (because so much of my system is half-customised)

Seems the best place to start might be:
http://www.alsa-project.org/main/index.php/Asoundrc
And more likely (see below):
http://alsa.opensrc.org/
And:

http://www.sabi.co.uk/Notes/linuxSoundALSA.html (interesting note at end of page )

I never really got anywhere looking into these things mentioned above. What I did do however, was use the H4 as the input device (along with its effects) and the Delta 66 as the output device - this can be done via qjackctl settings easily - and basically achieves what I wanted.