It appears (in light of some speaker suggestions mentioned above) that many have very low standards for what is "3D", "deep", "huge", "enveloping" or not... 😁
You could also get the Theoretica Applied Physics BACCH processor (forget speaker shopping)...3D holographia for ages! In support of your quest, it is a significant enhancement even if some speaker design you acquired is a bit of a dud.
But, if you do go with the higher end concentric driver designs suggested above (they can do a good job on their own..In fact, it is a characteristic trait of such designs). But, they can as well be taken to the umpteeenth level with BACCH.
Good luck.
P.S.
I use a TAD E1TX w/ BACCH. Not to brag here, but, you ain’t heard 3D envelopment from 2 speakers until you heard something like that. Following the science is generally a good idea for guys on quests.