Most agreed upon best speaker?

But, I've never heard a horn sound quite right,(to my ears obviously) in terms of just raw staging.
What is it that I'm missing? And which horns can and do stage accurately?

Perhaps it is the narrow dispersion pattern that gets you. To produce convincing sound that feels real for the room you are in it helps to have wider dispersion and EVEN dispersion (no discontinuity in beam width between drivers at the crossover). Not all horns are narrow. Not all designs suffer from abrupt changes in beam width. Some Westlake's and JBL's are wider dispersion - particularly the big bad 4 or 5 ways. Many of the modern horn designs have wider dispersion these days.

The Yamaha NS10's were a great little speaker because it forced engineers to concentrate on ensuring the midrange sounded good. These were a big advance from the Urei and Westlake, Lansing horns used in the 60's.

So I agree with Newbee that there is certainly an effect on the sound based on the monitors used. But given the variety of systems out there it is hard to identify a specific trend.

An NS10 used to get the midrange right followed by bass checks on main monitors and then a final check in the car on the way home has been a pretty succesful approach since the early 80's.

The problem with sloppy bass and recessed mids on many "pleasing" sounding speakers is that far too many errors get through due to masking effects. Elliot Scheiner still uses the NS10 or the latest version (MSP10) as far as I know. (If you think the Eagles and Steely Dan stuff sounds good then you know why)

Lately there has been a move towards more accurate monitors driven by the research by the likes of Dr Floyd Toole - monitors with wide even dispersion that load the room evenly and work in a variety of condition and not just close nearfield. This has eliminated the need for checks on multiple systems and resultyed in speakers that perfrom much more uniformly across different brands.

Part of the problem in the past was one of uneven dispersion meaning that the same speaker could sound completely different depending on the setup/surrounding (especially true with older farfield main monitors horns).

Today some people can even mix on main monitors (often in architecturally acoustically designed spaces) but most people still use nearfield monitors that are less affected by location/surroundings...so things have changed since the old massive Urei horn days when the likes of Led Zeppelin and The Who were blowing up speakers twice a week.

Here is a nice recap.