I suspect what's happening is that reflections from this thing centered between the speakers is giving listeners a more focused center vocal image. In my living room the family has a TV screen in between my speakers. I hear reflections off it's surface and I throw a packing blanket over it when I listen to symphonic music where I want better image localization across the area. Something small and reflective in the middle might make some things sound more highly localized.
That has to be one of the most expensive cymbals I've seen. Now that the rest of the world knows the secret Zildjian family secret alloy, here we go. I can't imagine deliberately putting something resonant in the room given all the efforts as resonance reduction from various other exotic gadgets sold in this arena.
Finally, I had to laugh at some of the user pictures on there. One had the "cymbal" right in between a pair of panel dipoles, which have a figure of 8 pattern. Thus the device was right in their null. Then there was a pair of corner horns put out into the middle of the room.
