Where should the vocal image be?

With the Spatials I own the center image is always behind the speakers. How far behind depends on the recording. Some tracks it's a couple feet behind, other tracks it's way back there. IMO this is why OB is great for smaller rooms and nearfield listening, as it creates more distance between listener and center image. Not necessarily an intimate presentation, however, if that's what one prefers.

When I play Roger Waters' Amused to Death album the barking dog at the beginning is to my right or 9 feet in front of the speakers and the old man speaking is to my left about 7-8 feet in front of the speakers.  That is just freaky.  I prefer the musicians in front of me where I can keep an eye on them.  Most of the time the images are between  just in front of the speakers to beyond the back wall (if I have the lights out) and can extend past the speakers left and right.  For me, the soundstage grows bigger with the lights out.

MC

Does SS depth really matter once you’ve screwed up everything else by using the speakers counter to their design?

Oh and you did allude to “one size fits all”. It’s the same with all your posts. “If you want audio nirvana, this is the only way” attitude is predictable but tiresome.

"Where should the vocal image be?

1. On the same plane as the speakers.

2. About mid way between the listener and the speakers plane.

3. Right up to the listener."

Whatever the musical material dictates. To me the in audiophilia often touted behind-the-plane-of-the-speakers presentation lacks overall immediacy, hereby loosing the ability of contrasting the source material properly. The converse scenario, albeit less frequent to my ears, is hardly desirable either; one is too stale and polite, the other too insisting and fatiguing even. Contrary to what many may expect though immediacy doesn't necessarily equate into "up front," but ideally alludes to a sense of presence - quite vital for music to come alive, as I see it. 

Height of presentation hasn't been mentioned, it seems, but here I'm not thinking of raising the acoustic center as much as the acoustic field from which it emanates. A taller speaker plane appears less restricted and thus also supports contrast of presentation. 

@phusis +Exactly what you said about immediacy and presence! This is exactly what I look for in music reproduction!

I seek vocals emanating from head/mouth attached to body at natural height. Without this one can't have believable illusion of performers in room.

Add sense of presence and human size images together, what you get is involving listen.