2way speakers

@audiokinesis

Agreed. You can’t argue the physics. Even off axis dispersion or even power response was discovered in the 70’s. I think reknown manufacturers like B&W know this but B&W has built a succesful global business selling designs with a hole in the mid range. B&W crossover a 6 inch woofer at 4 KHz (big mid range hole) and tend to boost their bass response too. B&W speakers all sound like hi-fi - boosted bass and boosted treble. Along with other manufacturers they have defined a sound that most people equate to hi-fi. It isn’t natural sounding and it is fatiguing principally because the ears/brain can’t quite make sense of the unnatural sound. It demands attention because it sounds different from everything else we hear all our lives. It sells well as owners are proud of the distinctly unnatural “hi-fi” sound. In a sense, the marketing department and magazines have educated us to expect this kind of exaggeration from “hi-fi” speakers. Natural sounding speakers do not draw any attention to themselves in the way “hi-fi” speakers do. Most well heeled buyers are actually more willing to part with large $$$ when they can clearly hear something different and attention grabbing. B&W know exactly what they are doing and it works! Great and tremendously succesful company.

@shadorne 

You're making the common mistake of judging the sound of a speaker entirely based on its response.

The fact of the matter is most hifi speakers I've seen reviewed in stereophile do have quite a flat response within a few db.

Why should anybody pay several thousand dollars more than a basic hifi speaker costing say 300 dollars if the only difference you're getting is a few db differences in the frequency response? 

B&W crossover a 6 inch woofer at 4 KHz (big mid range hole) and tend to boost their bass response too

B&w are using true phase cohesive first order filters so the discontinuity in off axis response is not as sharp as you think it is.

Anyway nobody should be listening in an untreated room so the importance of off axis response depends on your room acoustics.

If you move up to 3way in an attempt to even the polar response you now have further problems with trying to merge three drivers to make them sound coherent. You will need a bigger cabinet too.

As for boosting the bass, that's dependent on room and positioning too. There is no correct answer to how much boost there should be. You don't want the speaker to sound too thin or too warm or bassy. The response shown on the graph depends on how the measurement was taken

@kenjit

You are assuming that I stated that even frequency response and even dispersion is the only criteria for evaluating speakers. It isn’t. Dr Floyd Toole research conclusively demonstrated that these two factors are however extremely important.

To name just a few other important factors that a good speaker design must consider:-

Waterfall plot. Power compression. Crossover design & quality. Q of the bass response. Dynamic range. Intrinsic driver damping. Driver break up. Short coil in large magnetic gap (for linear response). Low hysteresis. Good driver alignment (no rocking motion). Good voice coil cooling from extremely tight tolerances to reduce thermal compression. Baffle design. Port design. Impedance and amplifier load. Driver sensitivity matching. Phase alignment of drivers.

But you didn't mention any of those before. You simply chose to focus on the response.