Speaker design without passive x-over?

Has anyone achieved success with a x-overless speaker in which the amplifier is fed the appropriate signals, (passive or active x-over before the amplifier).
I was told one of the benefits is adjustment of tweeter midrange and woofer levels to ones taste.
Tube amps will be used with tube preamps.
Do you mean the standard arrangement used in all active loudspeakers? If so, there are many, many success stories. Been there, done that.

Linkwitz Orion Plus.....read the documentation on the website.
The reason I ask is someone is proposing to me that I take this route in my next system.
I have reservations over building speakers since I lack the experience and know-how.
Nonetheless he is bent on this happening.
Of course I will not be making any moves until I hear it first which will happen some time soon.
So far I have come to the conclusion that even the speakers listed as class a in the mags don't exactly satisfy, therefore I doubt I can build something that I am after.
I recently have heard many different brands and the only three or four speakers I like are wilson alexandrias x-2 verity audio, mbl's and of course merlins.