Have speakers really improved within the last 20 years??


Question:

  • If there is one measurement that would prove that speakers have indeed got better over the last 20 years, what would it be? 

I dont just want one example of a speaker from today that has a better measurement than another speaker from 20 years ago because that could just be a coincidence. I want to see IRREFUTABLE PROOF that most speakers today have a measured performance in at least one area that is better than most speakers 20 years ago.

When I look at a typical bookshelf speaker from 20 years ago versus one from today i see little difference. All i see is a wooden box, typically mdf with a pair of drivers in 'em. There would be a small crossover circuit inside and a bit of foam inside the box and that would be the end of the story. I would like to believe that speakers have gotten better but I see no reason to believe it. All I see is that speakers may have gotten brighter and brighter with time to dupe us into thinking we are hearing more detail. 

This challenge is open to any audiophile or speaker designer reading this.
kenjit
I can’t quantify perception. I can only tell you that I take more enjoyment in listening to system A compared to system B. 
A Benchmark DAC measures perfectly. And yet many people dislike (or take little pleasure) in listening to that sterile, hyper-detailed studio sound and prefer NOS, valves or any number of technologies that might not measure as well but are perceived by their owners, in their systems, as more satisfying. 
Which brings me to point three. System. You can’t  judge speakers in isolation. The speakers are placed in a unique room.  They are connected through long wires to an amplifier. The amplifier to a source. Everything is connected to the mains. The mains matter. The electronics and wires matter. The room is almost as important as the speakers themselves and there is no telling how speakers are going to perform in a given acoustic space. 
If you would even begin to grasp the complexity of the answer to your question, involving architecture, physics and psychology, you would know better. 
Last but not least. People on this forum don’t obsess about absolute quantities or qualities. They take pleasure in this hobby and follow their own tastes and preferences. I buy a new set of speakers not because they measure better, but because I LIKE what I hear, in my room, with my electronics. 
Tastes also change in time, possibly in line with the physiology of perception. We have a much better hearing in our twenties than in our sixties. Much of the high frequency range is lost as our ear ages. I have seen, time and time again, people starting their journey with detailed, transparent solid state systems and ending up favouring a seductive, warm, valve glow. 
Very little in this hobby is quantifiable. In fact I would go further and say, this hobby is not an exact science at all and numbers are the least important measure of it. You can obsess about demonstrating X W or Z until your hearing is reduced to tinnitus. Or you can just find a good enough system to enjoy the music. 
I enjoy my system now than the one I had 20 years ago. And that is all that matters to me. 
A perfectly fine speaker twenty years ago is still a perfectly fine speaker.
I know my hearing's got worse over the last 20 years! (still don't like 'bright' speakers though to offset this). Am still happy with ESL57s and a sub. Have replaced older drivers in my Castles which has made a big difference.
Well, let's see.  Many manufacturers have copied Magnepan and now make speakers that are very tall.  I guess that would change the metrics you derive from measuring them.

Also, I would assume Mr. Winey's son is working to continually improve the Magnepan line over time.

So yes, there are speakers that have improved and probably "measure" better in anechoic chambers.  Since we don't have these in our listening rooms (most of us, anyway) possibly improving your room will suffice?

Cheers!
dekay: Remember kenjit lives across the pond and might night be familiar with your survey choices. For me, however Mary Ann of course.