Is the 2.5 way speaker the ideal home speaker?

@kijanki

I think the bottom line is that if a driver is crossed over close to 4kHz, it’s covering most of a human’s vocal capability that falls within the most sensitive range of our hearing ability. It keeps the crossover away from the meat of the music. Even if harmonics do extend as far as 17kHz, many folks have trouble hearing freqs beyond 8kHz.

Helo - 

I can't disagree with you in terms of the voice, but I will say, I just haven't found the upper crossover point to be a really clear indicator of performance either way. 

Most of the human voice in singing operates from 80 for very low bass male voice to around 1500 which is above natural female vocals to maybe someone trying to hit an extreme note to impress.
Everything that Erik has quoted throughout this thread is correct.
A couple of things that I thought of reading through the thread.
**Crossing a tweeter low: sometimes its a no brainer, the mid has a dip or peak and you need the tweeter to cover that range for a smooth frequency transfer... Other times, I have listened to the mid and the tweeter both at a given frequency and thought the tweeter sounded better and chose to cross lower for that reason.
The rule of thumb for how low you can cross a tweeter is 2x its resonance at 12db per octave. This can be broken depending on tweeter, but it is a good general rule to follow.
For me an optimal in theory speaker would be a 3 way crossed somewhere around 80 on bottom and 2200 to 3k on top. This keeps the deep bass off the mid which really helps keep it clean and it also keeps the crossover out of any critical vocal region. Of course finding perfect parts to put into practice are not always so easy.
Erik, you’ve done a great job with this thread. Getting folks to understand a 2.5 way vs a 3 way isn’t always easy.
Tim

This has been a great thread for me to understand a little bit better about something I enjoy. Thanks Eric for the thread and Tim with your long term experience in speaker building for all your supporting information.

Very good post , helped to clarify things I kinda , sorta knew .
I'll give you a joke I just heard on the local jazz station .
Announcer was interviewing a local retired trumpet player who still does some sub and gigs around the Twin Cities .
The dude had once played for Lawrence Welk , both of them rolled off the names of some pretty good musicians who played for the bubble man over the years . DJ kinda beat around the bush as to why so many good players
played the corn ball . Trumpet man said , "you have to be a hell of a musician to play that bad all the time "  !