Shocking 3D sound in 2 channel

Not all speakers can do this (although, I'd be willing to bet there are more speakers out there that can do this than most of us may suppose...and yet, also, I'd bet that most people tend to (mistakenly, IMHO) assume that this is somehow primarily (if not solely) a function of the speakers themselves. I've never run across any speakers that could do this "without fail" and don't really expect that I ever will. But, it's the particular electronics that the speakers are mated with that more often seem to me to be the determining factor and, just as with most speakers, this ability doesn't seem to be simply a function of price. I doubt you'll ever hear this sort of thing in any mid-fi setup, but it has been demonstrated even in some fairly minimal, but somewhat inexpensive, rigs (say, $4-$6k). Most sources these days seem to be ok for this, if your spending, say, $1k and up (although, with vinyl you may need to consider the cart, at some point). Some amps definitely seem to be better at the whole 3D thing than others - as a class, SET's come to mind, but this may be one of the few categories of any equipment that is, overall, singularly regarded as having this trait...although, you might also want to investigate any crossoverless speaker designs out there. Otherwise, results may vary widely and you may end up having to 'luck up' a bit on having a good combination of components for this (or you may run across someone else who has). It does not seem to happen that way all the time, but sometimes it does. Some preamps are better at it than others, too. A pre should be either of very good quality or better, or perhaps not in the signal chain at all (stepped attenuators and the like). There are plenty of other factors that can have a direct bearing, but I view speaker placement, wiring choices, successful levels of power conditioning and etc as simply things that can occlude the 3D effect if not done well, but after having addressed ALL of those things, they may not in and of themselves alone result in true 3D realism - much harder to get there without them, yes, but the underlying key to me seems to be hitting on both the right electronics AND the speakers themselves, as well as the quality of the match the speakers provide to the electronics...and even Then, that doesn't Always produce the desired effect, but it still looks to me like the best shot we generally have.