Larry, what is under the "Settings" button on your MixControl. Does that have a similar adjustment to my FireWire Driver Latency?

mettelus
Larry, what is under the "Settings" button on your MixControl. Does that have a similar adjustment to my FireWire Driver Latency?

When I click "Settings" I get a dropdown with only one item: "ASIO Buffer Size." Hovering over that reveals a long menu of items incremented in milliseconds, from 1.0 ms at the top to 20.0 ms at the bottom. For recording and monitoring through the DAW I had to go to the second lowest time, 2.0 ms. I don't know how that translates into buffer samples. I've seen a formula for that, but don't remember it.

I was curious, since I have never seen the Scarlett version. With the numbers you are getting, this seems higher than expected to me. Have you tried the lowest setting (1msec) to see if you get any pops/crackles/dropouts?
 
As far as the "math," the easiest way to remember things is with units. Sample rate is samples/second, and your buffer is in milliseconds, so if you convert the buffer time to seconds, your units will cancel out to make sense.
 
Example: 44.1 = 44100 samples/sec and a buffer of 1msec = .001 seconds. Multiplying them gives units of "samples-seconds/seconds" and the "seconds" can be canceled top and bottom, so is just "samples." so in 1msec at 44.1 you would see 44100 samples/second * .001 second = 44.1 samples.
 
Similarly, 96000 samples/second * .0112 seconds (the 11.2msec RT you mentioned above) = 1075.2 samples (which you said was 1078, close enough since the RT is rounded off to 11.2).
 
Sample rate * time = samples (in that time)
Samples / sample rate = time
Samples / time = sample rate (this one is easy, samples/seconds = samples/second )
 
Just be sure the units used all match.

mettelus
Sample rate * time = samples (in that time)
Samples / sample rate = time
Samples / time = sample rate (this one is easy, samples/seconds = samples/second )
 

So at 96k with a 2 msec. buffer, the buffer sample size is 192. I was at 256 on my PCI card. So while the Scarlett is doing the job right now, I have to push it to the limit to get acceptable performance on my fairly simple projects. There is no "bench" if my projects get more demanding and require more oomph from the interface.

That is the correct stable driver. Mix Control 1.8 and the audio driver is 2.5.1,,  I just checked mine
And I get the about the same results at the same settings as you, I just tried that too. 
I think it's the hidden buffer issue as I don't "feel" any latency even when working at 44.1.  
 
My conclusion is unless you spend $500 or more your dealing with pour performance in RTL. All low end usb interfaces seem to perform about the same. But it is possible to get under 12 ms at the higher settings at risk of your system become on the edge. So you just have to raise and lower the buffer as you work. I leave mine on the 10ms setting 90% of the time for everything but messing with Guitar rig. And I'm not even using Guitar rig to record as I prefer my own pedals and set up, but it's a fun distraction form real work...