Re: [linux-audio-user] Advice on FC5

Lee Revell wrote:
> On Tue, 2006-04-25 at 08:48 -0700, Tim Howard wrote:
> > Thanks a bunch, Fernando! I just realized last night that my system
> > (FC5 OOTB + Jack and Ardour) has about 42ms of latency, which I don't
> > think qualifies as low latency...
> >
> > I do really like FC5, though. We'll stay tuned for a kernel release!
> >
>
> Are you sure you're running realtime? How do you test latency? What
> happens if you try to go lower than 42ms?
>
> Lee
>

Lee, I'm a real newbie at this... <smacks forehead> But I'm learning slowly.

I didn't realize that the "42ms" of latency displayed by qjackctl in
the setup section was NOT my system's "absolute lowest latency,
take-it-or-leave-it."

So when I loaded CCRMA's RT kernel for FC5, I was surprised to see
that latency number stay the same... Then I started messing around
with the frames per second setting, and got the number down to 5.333
msec (128 frames/sec), with a noticeably improved response time for
softsynths, for example.

I have tested this setting for xruns, and I haven't gotten any yet. I
was playing back with 8 tracks, about 12 LADSPA effects, and recording
1 stereo track, and it was fine. (That's about the most I ever do.)

What I'm wondering now is whether the stock kernel would have also
been able to work acceptably, since it could also run in RT... Hmm,
I'll have to go back and check that out.

Is there a better way to check latency, BTW?

Thanks for clueing me in, Lee.

-TimH
Received on Thu May 11 04:15:04 2006