I made a prototype quad panner for Max that sends data to Ableton Live. There is an XY controller that sets position in terms of left / right / front / rear. This data is then sent to one of 32 tracks in Ableton Live. The track number is selectable in the panner patch.
In Ableton Live, each of the possible 32 tracks features at least four sends, corresponding to front left, front right, rear left and rear right. Each send would be routed to a separate speaker.
You might ask yourself why this has been done using a standalone Max patch rather than a Max for Live device. It's more about real time control of sonic elements within a performance rather than setting positioning for a mix. Time and interface efficiency are paramount. The quad panner accepts MIDI for controlling track number, XY positioning and data muting.
I haven't tried it out yet. But it should work. The panner calculates equal power distribution in both planes.