Single driver vs traditional 3 way loudspeakers

I used super tweeters with Altec 604E coaxial for many years.
I also listened Altec 604E without super tweeters for couple of years.
For last two years I use Fostex T90a super tweeters.
It is always was some trade off between “audiophile” sound with super tweeters and more “musical” sound without.
Super tweeters make sound more refined, more air, detailed… But harsh in upper midrange, more fatigue, more smearing.
But when I changed super tweeters 1st order crossover to 4th order – the results I got are win-win! I got all the best all together! The sound is even more refined, detailed with huger soundstage and clarity versus 1st order crossover. On other hand it smooth (no harsh, no smearing), even more musical interpretation details compared to without super tweeters configuration.

I think the same should be true when using super tweeter with full range driver!
I wonder, why most people use super tweeter 1st order filters? It Is so religion stubborn stupidity!

Most of classical speakers like JBL L300, Harbeth HL5 use super tweeters thought 3rd order crossovers.

Footnote: I went back to larger multi-way systems since I have a large listening room and wanted to listen to the full dynamic range of a large symphony orchestra going full tilt at actual live levels. I didn't want to be concerned with a voice coil wizzing past my ear.

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My classical music has come completely alive with my whizzer WBers. 
Incredible soundstage. 
Not sure what WBers you are talking about, Surely not Tang bands best nor DavidLouis best WBers, can't be. 
You must have heard some low class WBer

A 3 way design will most likely "blow away" everyone at first listen compared to a single driver.


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Correct,.
Big Wilsons, Dali, Sonus Fabers will be very impressive in the 1st session,, Once you get them home,,, well thats a  whole nother ball game.
= fatigue sets in,,then you feel like a  fool.
Been there DONE that. 
Wouldn't trade my dual WBers for any speaker in the world.

Yes, the tweeter has a High-Pass filter, but no crossover
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I'm running my paper  cone tweeter (yes I did say 1970's style paper tweeter, Kasun) witha   single 2.2 Mundorf SESGO cap, sounds super duper, 
vs the Seas Millennium tweet
like 8 components, 18uf, 2.2, 3.3 2.2 and perhaps 1 more cap!!!! ARRGHHHHH, trash.
All you need for a  tweet is a  simple single cap 6uf-2uf , xovers drain the life out a  tweeter.