[LAU] hardware - Intel CPUs

[Len Ovens]

On Tue, 15 Apr 2014, david wrote:

> Interesting. What is the difference between speed of sound in air and the 
> speed of electricity through a cable?

I was talking about through air. I can only play as fast as I can hear and 
at thirty feet or so from the sound source, my instrument sounds delayed 
from the rest of the band because I hear their sound that much later and 
play my part that much later. I don't normally play at that distance, but 
ten feet is pretty standard.

> I think the lowest I've had my UCA-202 (USB 1.1) card work at was around 
> ~3msec latency (on a USB2 port) with a Debian RT kernel just fooling around 
> (no other RT optimizations on this 2.4GHz i7 laptop). I've had Yoshimi 
> problems when latency gets too low on my stock kernel. And when I first 
> tried Zyn, it had problems at much higher latencies than Yoshimi did at the 
> time.

Is that measured round trip? Or one way through the jack part? What sample 
rate? (I'm using 48k) I can get qjackctl so it says I have .6ms latency. 
But I think that is one way, 1.2ms ... then add ~1 ms each way just to get 
through the sound card monitor mixing and maybe a bit more and I have 
already three and a half ms. Then I am some distance away from my monitor 
too. Perhaps with a newer faster CPU I could run at 96k and work with a FW 
device and get the same results. USB is very handy for many things but for 
sound it takes some playing around to get a clean low latency set up.

However, it looks like I can still get lots of MB with PCI slots in them. 
I will probaly do that. Hopefully with three PCI slots I can get one that 
is irq clean.


--
Len Ovens
www.ovenwerks.net