Speaker of the Century Award Goes To ....

The 2.5 way speaker.

You guys probably thought I was going to fanboy over a brand, and I'm not. I'm going to fanboy over a speaker design. IMHO the 2.5 way speaker is THE ideal high end speaker for the majority of enthusiasts.

First, what is a 2.5 way? It is a speaker with 3 drivers, but the mid range lacks a high pass filter, so  it shares output with the woofer.  It has a number of advantages over smaller and larger speakers:
  • Similar footprint to stand mounted 2-way speakers
  • Ideal bass output for apartments and modest homes
  • Easier to integrate than big speakers
  • No subwoofer
  • High sensitivity compared to a 2-way using similar drivers
  • Reasonably priced

A number of brands have taken this approach including:
  • Focal
  • Joseph
  • Monitor Audio
  • DIY kits like the Klang Ton Ophelia, and Zaph Audio

So for the average enthusiast who is not a San Francisco billionaire I argue here (for the sake of an argument) that the 2.5 way speaker should be considered one of the great technical innovations in terms of users and results.
I am 65 and can still hear 18,000 Hz just fine. I do not normally play at 110 db but I do have a sound level meter and the system will go that loud w/o distortion. A comfortable loud volume is 95 db.
Tweek, properly set up Acoustat 2+2s with sub woofers and 200 watt class A amps are so much better than Pipe Dreams which could not throw an image to save their lives. 
BDP  We use to stack quads and with Hartley sub woofers. We could get 95 db out of them but we still use to blow one a week or so. 
I am 65 and can still hear 18,000 Hz just fine.

Are you positive?  How did you determine this?

That is extremely unusual.

I'm 55 and have protected my ears.  When I get audiology tests those giving me the tests usually express surprise, saying I have the hearing of a younger person.

Until recently I could hear up to 15K, but that's dropped to 14K (with a little dip around 4K).

Age related hearing loss takes an even steeper decline usually after age 60.

So I have to admit some skepticism about your claim. 

while i own and enjoy a very nice set of 2.5 ways, i do hear some midrange congestion compared to previous 2-way and 3-way systems.  not bad, and these speakers are touted for being among the best in this category- but still noticeable.  
i would rather have a true 3-way system, especially if it allows bi-amp capabilities.  
First, what is a 2.5 way? It is a speaker with 3 drivers, but the mid range lacks a high pass filter, so it shares output with the woofer. It has a number of advantages over smaller and larger speakers:
I've always seem this as a poor implementation. I get the idea- the mid bass/midrange driver goes down pretty low, so if you crossed it over, the crossover would impose a coloration due to the size of the capacitor(s) used.

But in practice they are problematic. Of course from my perspective this nearly always means is a bad load in the bass - meaning a lower impedance so more distortion from any amplifier. But further, you can have doppler effect distortions from the mid range unit as it can have a bit of excursion, unless carefully damped by a sealed box, but that does not solve the problem of the voice coil having to absorb a considerable amount of power!

Now for the anecdote: YG Acoustics was advertising at RMAF a few years back that they made the 'best speaker in the world' bar none. I went to audition their speaker at RMAF; I brought with me Peter Gabriel's 'Rabbit Proof Fence/Long Journey Home' soundtrack. In the first 30 seconds or so is a fairly large bass note. I played it at a level that I can play easily at home on my Classic Audio Loudspeakers. When the bass note hit, the mid/bass driver rattled quite loudly! against that wire cover they placed over the driver. I think the salesman thought it was some sort of synthesizer midrange note played loudly but it was really something that should have shook the room. I can name plenty of speakers that don't do this.

So I don't buy that this as a good technique at all. I've always viewed this approach as a bit sloppy and I don't think I'm going to be easily convinced of otherwise.

it could be your speaker cables. Recently I made a huge SC upgrade and was blown away at how they cleared up issues I never would have thought was SC related