usb audio latency

[Tony Hardie-Bick]

M-.-n wrote:
> I'm kind of curious to know what's the lowest latency you guys have 
> achieved with standard usb audio under m$. I don't seem to be able to do 
> a lot further down that 256 samples through asio4all, even with fairely 
> lightweight programs.

Hey Marc,

I was checking this out a couple of yrs ago, and, basically, the USB hardware 
imposes a non-reducible latency of several mS. I never studied it further than 
that, cos it ruled out USB for the application I had in mind. Of course, the OS 
imposes a bit more latency too, and given USB isn't suitable for low-latency 
audio, most software stacks feel free to add a few mS of their own, in order to 
get reliability without imposing too much on the host OS.

The man who *really* knows, is Jay, but the poor guy may still be a bit too 
traumatized to talk about it ;)

Tony (HB)