Where should the vocal image be?

Dependent upon speakers, rest of system, toe in, room and room treatments, recording. But generally, I've heard center image vocals as mostly in or behind plane of speakers, only hard panned vocals sometimes extend in front of speaker. This has been a constant with box, open baffle and horn speakers.

The XLO disc is good for that image placement track.

@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.