Is the 2.5 way speaker the ideal home speaker?

A 3-way design should preferable, at least in theory, but it requires an additional type of driver and a more complex crossover network, and both of those increase the cost.

and often degrades transparency.

I'm not sure I follow, @helomech -

Usually higher tweeter points are achieved with 3-way systems which use a "true" midrange.

It's just my experience that 3-ways often lack the transparency of a good 2-way, I can only guess it's due to the additional crossover components. A good example is the 2-way Maggie .7s vs the 3-way 1.7s. The latter is less resolving.

@helomech

That's interesting, usually three way speakers are considered ideal due to the midrange covering the entire human voice and much of the piano without the crossover involved.

I wonder if your hearing more bass boominess from 3 way designs?
 

Yes, some 3-ways have a single driver covering most of the midrange (though many still crossover to the mid around 2kHz, largely negating that advantage) , but even though the crossover point may not be smack in the middle of the midband, it still requires a more complex crossover with additional components in the signal path. The whole signal path of the midwoofer need be considered when it comes to signal purity, not just the crossover points.   

I can't tolerate much bass boom, so no, that's not the issue. I have a room that can accommodate very large floorstanders. I prefer large 2-way standmounts with subs to augment the bass.

Another issue I find with many 3-ways is their small and/or recessed vocals. A vocalist simply won't sound as full and present through a 3" cone as they will via a 7+" cone, nevermind the beaming argument. This is why some designers, B&W for example, refuse use small mid cones. 

I understand the theory behind the proclaimed advantages of 3-ways. It's just that in many cases, my ears cannot detect a practical advantage outside of maximum loudness capability. They can play louder before compression kicks in, or before complex music trips them up, but it comes at the cost of lower resolution at moderate volumes. That's been my experience. 

Hmm...seems no one pointed out the real advantages of 2.5-ways (at least well designed examples). It's the same advantage of 2-ways: the high crossover point and resulting coherency. In a well designed 2-way, it's often difficult to make out the separation of drivers, whereas I rarely encounter a 3-way that achieves the same feat. I can usually hear that there's 3 or more drivers doing the work.

A midwoofer and tweeter crossed over at say, 3.8kHz, benefit from coherency and lack of crossover distortions where the meat of the music lies: in the midrange. This is largely why speakers like Harbeths and Spendors can produce vocals that rival some electrostats. 

Of course there can be disadvantages to a high crossover point, but I find they are insignificant or inaudible in most high quality 2/2.5-ways.

@erik_squires 

I'm not sure I follow, @helomech -

Usually higher tweeter points are achieved with 3-way systems which use a "true" midrange.

That's why I stated, "well designed examples."

I know of quite a few 3-ways that are still crossed over to the tweeter rather low, often in the 2kHz range. Some 2-ways are crossed this low, but it often doesn't work so well IMO. There's no hard rules in any of this, but I rarely come across 3-ways that have the coherency of well designed 2-ways.

Eric,

The only 3-ways I currently own are Klipsch Heresy IIIs. I just looked up their crossover point, it's a rather high 5kHz. These speakers still lack coherency unless listening from a distance of 11' or more. I would guess that is most likely due to horn beaming, though the others I mentioned also benefit from such distance. I sit about 9' from the speakers in my main rig. Of all the 3-ways I've tried, none work for me in such proximity. I imagine a design like the Elac Adantes might work.

@grannyring 

I made that point early on and it is one of the best advantages. That is why I also like a simple two way design.  Nice post.  

My apologies, I overlooked it.

^ Eric,

Revel F206 : 2.1kHz

Monitor Audio Silver 8: 2.7 kHz

Paradigm Monitor 11 v7: 2.2 kHz

Paradigm Persona 3: 2.4 kHz


The first 3 I auditioned extensively. I owned the Silver 8s for a year They all lacked some coherency IMO. 

@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.