I'm with a touring theatre company. Looking at a box + iPad digital mixing setup (XR18, A&H Qu-SB etc.).

But: we work with a multi-speaker setup, and I need (at least) 4 outs where I can pan within any pair of them. Presumably, I need either stereo aux or buses that I can allocate a pan (knob?) to. From what I can see, XR18 doesn't allow this, the pan only applies to the Master Stereo outs. Qu-SB seems possible. Any others?

For theatre, I use MOTU AVB units which usually have more outputs than inputs.

To design similar moments, I'll set up specific aux's to be patched to specific outputs, and then build a Qlab cue which sends an OSC command which look like this:

mix/chan/<#>/matrix/aux/<#>/send

In Qlab, you type in a value from 0-4 (0 for -inf, 1 for Unity, or up to 4 for +12) and then type in a fade time, so it's locked in and smooth.

The programming can take a minute, because channel numbers are obnoxiously offset by one (Channel 1 is 0, so therefore Channel 5 is 4, ect.) and as written above, the OSC values aren't 1:1 with send values.

Though once you've got your programming started, you can copy/paste cues as you need them, and it's all super consistent in a way which is useful for live theatre.