2 way vs 3 way question

A 4 string bass guitar's low E string is 41hz, and a 5 string bass low B is about 31hz, and a lot of ambient, drum tone low frequency and other normal stuff exists below 40hz in music. A good sub or two will make a full range speaker seem to sound much better (magic!), and the low frequency "hall sound" on live recordings helps things sound like reality. Subs "charge the room" which, if you get used to them and simply turn them (or it) off for a bit you immediately notice the life force going out the window, so to speak.

wolf, normally u and i fully on same page...however it is not like 2’s have little output below 40, in fact the acoustic coupler is capable of much...
i would MUCH rather a good two or three way than poorly integrated HT sounding subwoofers.....which is all to often the norm...sadly..

but because I like precision and not jazz ( i am expecting you to get this Wolf, if anybody does )...

the model 2

29 to 29 KHz plus or minus 3 db
and a fantastic 
32 to 21 KHz plus or minus 1.5

hammer down on low B

maybe I should give up my dinky Taylor bass.....

Instead of asking for the best from a theoretical point, simply ask what’s the best speaker you can afford. 
 
If only looking at new: 
 
KEF R3, KEF R300, Philharmonic BMR (unless you sit far away), NHT C3/C4, Revel M105/M106, and Selah Audio Onesto. Those are the ones I can think of off the top of my head as being some of the best out there at their respective prices.