Unlike most box speakers, Panels have 4 orientations which are valid. Only the 20.x series, which is push / pull has a pole piece on each side and therefore has only 2 possible orientations.'
When I first installed my panels, I had them as 'recommended' with the tweeter to the outside and pole piece ot the front wall. This is easy since the connection panel is 'back there'.
I was never happy with that setup.
I eventually flipped 'em in place and got the pole piece to the front and the tweeters to the INSIDE of the panel. I think because of the 2nd order lowpass and 1st order highpass, the 90degree difference produced a lobing effect which effected image and balance.
So after running for several months pole piece to the listener / tweeters in, I made the big change while doing a tune up.
All speaker connections redone and deoxite treated. Fuse pulled, ohm'd and deoxit. Panels flipped L/R and tweeters put IN with the pole piece rotated to 'as intended'.
Nice change. Tweeter position is CRITICAL in bilateral symetric panels. Now, the image is dead stable. The next experiment will be to move the panels further apart. They are now at 60" inside edge to inside edge. Very expansive stage and I'd judge there to be better HF dispersion and extension........