Is Speaker design evolution stagnant


Based on what I read from speaker manufacturers, many use the same drivers but apply different crossover philosophies to achieve a particular sound.

My simplistic understanding is that while limiting the range of high or low signals , the remaining signal is corrupted ( phase inversions, roll off, etc.. ).

With today’s technology, why aren’t more speaker manufacturers using active crossovers to be connected after the preamp and sending exact spectrum signals separately to be amplified to each driver.  That would Eliminate all electronics inside the speaker cabinet except the drivers. Each driver gets fed only the signal that it works best at. No out of phase, half phase, quarter phase issues, no phase angle issues. 100% of the power goes to each driver without limiters to scale it back.  I think Bryston Model T Actives is designed this way ( don’t work for them and not pushing any product). Am I looking at it too simply? Do electronic crossover play havoc on signals the way inductors and capacitors do?

Some speaker manufacturers have gone half way with built in woofer amps ( Vaughn?)

Of course you would need a 3 channel amp for each side ( based on W/M/T config) or some variable of mono amps, whatever.



jacksky
I would not say development is stagnant, maybe just turning in a direction away from whats been done for years in one form or another to a new direction fueled by new materials and theories. Back in the infancy of speaker development, Kellog and Rice of Bell Labs patented a new speaker technology the electrostatic speaker, it used stretched pig intestines applied with gold leaf to hold a static charge as a diaphragm material, obviously it had its drawbacks !!
Mylar, the diaphragm material needed to make this tech possible was still 18 years away.  
Same holds true today.new materials and applications will open up new possibilities.
For instance, check out this video  https://youtu.be/HGOt3JhrUs0
Graphene can be exited and caused to radiate sound by beams of light modulated by a music signal. Cool !!
Greg
There was also work with ultrasonic transducers which vibrate the air at frequencies the ear can hear with very directional properties.
It could lead to music aimed at you like a parabolic dish which only you would hear, like headphones but nothing on your head.
https://youtu.be/4eZVF1ouTT4
https://youtu.be/hmNzf9ztnAk

Greg
Erik,
so tempting to build my own, but I have to admit......I’m afraid.  So much to learn.  Before I make a choice of any component, I may end up looking at all the alternatives to make sure I make the best choice.  I am not afraid that everything on paper looks good but the actual audio  result may stink.  I can live with the journey and failure, just don’t know if I am up for the amount of learning work involved to understand theory and apply math.
i really am not at the semi engineer level that many of you kind posters are. 
But I will look at the other forums and see if I can follow.
jack
@jacksky -

Build a pre-designed kit. Start there. Something inexpensive. After you have built it, you can tweak it to your hearts content.

Building a 2-way kit would answer most of your questions, and leave you more expert than most people. 

Best,

Erik
Greg,
fascinating technologies, Really fun stuff.  Great practical applications.
I think plasma speakers are pretty cool too.

Faxer,
in the 70’s I saw foam flat panel speakers. They sounded eh...ok at low volume.  The beauty is , as you stated - single driver so no crossover.  But if you pumped more power into them they would catch on fire.