[PlanetCCRMA] M-Audio Audiophile USB

Michael Peters mpeters@plusthree.com
Sun Oct 2 18:25:00 2005


Fernando Lopez-Lezcano wrote:
> On Sat, 2005-10-01 at 15:25 -0400, Michael Peters wrote:
> 
>>Rui Nuno Capela wrote:
>>
>>>Michael Peters wrote:
>>>
>>>>But that still leaves me with the problem of having it appear in the
>>>>connection window, audio tab under Qjackctl. The midi appears just fine.
>>>>Any pointers?
>>>>
>>>
>>>Let me clarify something I believe you're missing:
>>>
>>>If you're seeing at least one "alsa_pcm" entry under the Audio
>>>connections tab, than that's a sign that things are working properly, as
>>>expected. Those are the official names for the client ports that
>>>represent your soundcard interface, as thru the designated ALSA JACK
>>>backend. You must have jackd started alright, before you see anything of
>>>this.
>>
>>I do see one alsa_pcm (with capture1, capture2, playback1, playback2)
>>but I see that one without the usb m-audio audiophile connected. I know
>>that one works as I played with recording from the on-board sound card
>>(intel8x0) when I was just getting started.
>>
>>Since the USB card doesn't come with a mixer how do I select the
>>inputs/outputs of it rather than the onboard sound card? I assumed they
>>would show up in the connect window in qjackctl and I could pick from there.
> 
> 
> Jack can only use one card at a time and yours is not the first one
> which is the default (see what you have in 'cat /proc/asound/cards',
> they are there with a zero based index). 
> 
> You can choose which card in the "Setup" dialog of qjackctl, yours
> should be, I think, "hw:2". USB soundcards are tricky to set up to work
> well with Jack... try with 3 periods or more and sampling rate of
> 48000. 

That's the piece of info I was missing, thanks. But "hw" doesn't work
and after poking around on the alsa mailing list archives I found that
since the USB Audiophile is big endian I have to use "plughw". I can now
playback from ardour through jack. I haven't tested recording yet, but
that's for another day.

Thanks for the help.

And if you don't mind another dumb question... what's an "xrun".  During
the playback with new USB device I get about 1-2 a minute. I know
everyone tries to minimize them but I just wanted to know what they were
and what is the general strategy to take to try and reduce them.

Thanks again.

-- 
Michael Peters