[LAU] recommendations for usb sound card?

[Dominic Sacré]

On Sunday 09 March 2008 12:12:24 Hartmut Noack wrote:
> > James Stone hat gesagt: // James Stone wrote:
> >> Do you have any idea what kind of latency under jack I would
> >> expect from a CM-106 based card vs. a "Burr-Brown from TI"
> >> chipset (Behringer UCA 202).
> >
> > All USB cards (in ALSA) have the same latency.
>
> Is that a fact? [SHOCK] So, if I use a Edirol UA-101 for appr. 550 Eur
> it would force me to use the same settings for jack (for 17ms that is)
> as my crude Behringer U-Control??

You should be able to achieve much better latencies than that, even with the 
U-Control.
I can run all my USB devices, including the crappy UCA 202, at 4ms latency 
(48000/64/3). I don't get any xruns, except when starting some JACK clients 
(but there a higher latency doesn't help much either).
This is with a -rt kernel, of course, and tuning the IRQ priorities with chrt 
made a huge difference. I got the best results when I increased the 
priorities for rtc and usb, but not for the machine's built-in soundcard 
(which I don't use at the same time).


Dominic