Latency Measurement

So it seems I started a bit of excitement and David Jameson asked me to repost here.
My latency numbers come in well under what the software reports.
When doing the loopback test with the patch cable.
As in Apollo Twin (latency comp. Off), set to 48 or 48k, with 32 or 16 sample buffers measures at under 2ms, reports at over 5 from Twin.

Thank you for posting here.

Could you please try the measurement again, but please make sure you do not have any plugins loaded when performing your test.

you can hold down the SHIFT key when starting GP and it will not load the last loaded gig file. Then try to measure again and let us know.


Here it is…

I believe with 64 samples @ 44.1khz the minimum theoretical possible round trip latency would be 2.9 ms.

You may have some setting in your interface routing the digital signal out straight back in, without doing the D/A conversion and then A/D back in.

If you repeat that test without any physical audio cables plugged into any of your inputs I suspect you’ll still get the same latency report, which would be a pretty good indication it’s not really measuring a “real” round trip latency.

@Vindes is onto something here. If you do not use the patch cable - does this still work?

Also … from the picture I can see that channels 1 and 2 are at their maximums. If you used only one patch cable and did not load anything into GP this should not be possible unless you routed something internally

I routed in to out in GP on a new rig…so I guess I shouldn’t.

Yes - please do not do that. Do no route anything to anything else - just run the tool and post the results here.