I am also wondering, if the QU-SQ connection introduces extra delay as opposed to AB168 stage-box?
What is the expected delay introduced when connecting SQ-AB168?
Using inputs from different devices/sources will definitely affect the latency. Most people don’t realize it, but in the Allen and Heath systems there is a difference in total latency between local I/O on the console and I/O on a stagebox connected to the console (with the stagebox being more latent). Certainly connecting two consoles together and using I/O from the second system is going add even more latency.
I don’t know how much that latency will be, but I doubt it will be very much (I’m guessing less than 1ms). If you use inputs from a variety of sources (local I/O, stagebox I/O, I/O from second console, etc), you will have different total latency times for each source type. Depending on the actual inputs, this may or may not cause an issue. Generally it won’t cause an issue unless you have inputs spread across multiple connection sources that are picking up the same source sounds. For example, if you have your drum mics on local I/O and some stagebox box I/O as well, it might cause some phasing issues. If they are all on the stage box and your other inputs are local I/O, it probably won’t cause an issue.
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