Sorry if I was misleading.
The sentiment (and the question I raised) remains the same.
Allow me to rephrase:
"High end" headphones - why aren't they ALL planar magnetic?
For example - the Sennheiser HD800 is highly regarded, yet it is dynamic. Do dynamic drivers in this size have advantages over planar magnetic?
Without knowing the actual area and excursion of the HD-800 ring radiator drivers versus popular planars, I can't make a guess as to which is superior in terms of surface area - which I think is a critical determinant of any speakers performance. As with automotive engines, I tend to believe that 'there is no replacement for displacement'. If you can move more air, you can make more sound, simple as that. You can either accomplish that with a large stroke (excursion), or a larger bore (cone diameter). Going to one large concert helps illustrate what I mean: you usually see more, bigger, not less / higher quality.
I would tend to believe that most driver decisions are a function of efficiency, performance, and
cost. I don't see planar's ruling the audio landscape because I don't think they have as long a development history as dynamics, and may tend to be inferior in terms of efficiency and cost. The HiFimans I currently enjoy are 'inexpensive' supposedly because of simplified design and low cost production (which is in part do to production occurring in China). But they are still bulky, and the overall sound is not 'perfect' (a tad too hot). Furthermore, amplification is needed despite their relatively efficient design. While I think part of their 'effortless sound' is a function of driver area vs. my other dynamics, many people still prefer other phones which I would think are technically inferior.
So, to answer your question, I will defer to economics. Most 'high end' headphones are NOT planars because headphone manufacturers will tend to
a) be technologically committed to dynamic technologies (i.e. they have 'sunk costs', or past investments in the technology which make them less likely to switch to a whole new approach to drivers / headphone design)
b) Perceive planar as less efficient / higher cost technology
c) are unwilling to do the R&D necessary to develop alternative driver technologies. Planars are having a renaissance because newer companies have sprung up to develop them and target a 'niche' market (or because advances have made planars more economically attractive). Although, my own logic wouldn't explain why HifiMan is willing to develop dynamic
and planar headphones. But do notice that their lower-cost phones are all using dynamic drivers. Perhaps their sticking with planars at the high end is partly an admission that they could not do a high end dynamic on the caliber of Sennhesier that could compete on terms of performance and cost. But they can produce extremely awesome planars at prices that compete with the best dynamics.
The top reason I might pass on planars in my living room is that it seems that placement is more difficult because of the flat front and back waves they generate. Oddly, they may also still benefit from a regular dynamic subwoofer since they do not reach into extremely low bass.
I would pass on electrostatic speakers because they need a constant charge to work - meaning they might use more energy over time than comparable speakers (and I care about the
environment so efficiency matters to me).
Here is also a link to some marketing / information about planars:
http://www.wisdomaudio.com/sage_series-why-planar-magnetics.php
I would think the flat impedance curves, tendency for greater 'speed', and large surface area are important factors in making planars a good starting point for high quality sound.
