How about a trifield stereo set up with 3 Phantoms

[ogs]

Interesting! I am curious how the dialog would handle the processing. Since recordings are in stereo, would centre channel be a summation of L/R or only common signals, which ostensibly to me should be the case.

Dialog would need to have special processing to create a proper three channel signal from stereo. It is indeed very interesting, but I have seen no mention of this from Devialet so I doubt it exists. This is actually multichannel so it should be possible to play back full mch material too if one adds rear speakers.