Wilson Sophia 2: grills on or off ?

In my system the difference is quite substantial. There is more detail and air with the grills taken off.

That is an unusual observation - the normal effect of edge diffraction is a "claustrophobic" or "cluttered sound" - the sound also becomes more identifiable as coming from each individual speaker rather than imaging somewhere in space between the two speakers....most noticeable on the sound of cymbals which may collapse in soundstage.

However, the very small triangular baffle of the Sophia mid and tweeter means that this issue may not be noticeable at all - you still get edge diffraction but it occurs so close to the primary signal that your ears may not pick it up ( this is why thin speakers and small satellites often do the "disappearing act" so well ). In this case, perhaps the grill itself is introducing an altered form of edge diffraction that you don't like. In any case, it is almost universally accepted that smooth rounded baffle edges are better than sharp edges, which is why it is usually best with the grill on.

I have Sophia 2's as well. I always listen with the grills on. For me, whenever I take the grills off I can see the speaker diaphragms moving (woofer and mid), even in a dark room, and this dramatically takes away from the illusion of reality for me due to my shift in concentration.

I actually prefer the sound of my WP7s with the grills on. I do hear a slight, but noticeable increase in high frequency "sparkle" and definition with the grills off, but I feel that this comes at the expense of a slight degree of smoothness that is of more value to me.

I had the Sophia 2s and preferred using them with the grills on...seemed to have a modest...very modest impact at taming the somewhat hot high end to make them more musical...I suspect, pure guess on my part, that they were designed to have the grills on...can't spectulate on the 7s or 8s...but I suspect the same would be true on the 8s given the more thoughtful grill system...

John