Where is this notion coming from that headphones produce sound from their enclosure material? What you want to AVOID is adding coloration to the sound. Even if we say for a moment that adding wood to a headphone lets them more accurately reproduce wooden instruments like violin, piano, etc., then your argument is going to fall flat when the topic of brass instruments, electric guitar, and any other kind of music comes up.
If a certain coloration sounds best to you then that's fine, and it's your preference, but in general a neutral and uncolored sound is sought after in hifi. I'd bet that engineered polymers are more likely to act neutrally than arbitrary woods. At least with polymers you can actually chemically adjust them and mold them to achieve the ideal sonic properties you're looking for.
As for bright versus dark, I'll just say that I have never heard a real life violin or trumpet that did not have piercing and vibrant treble all the way up to 20khz (and probably beyond). You may very well dislike that, and that's okay, but don't disillusion yourself and others to think that real life is dark sounding. While my dark HD650s are remarkably natural sounding, they do need a bit of a treble boost to avoid brass and string instruments from sounding like they're playing from inside a foam-padded cell.
Anyway, it's not too surprising I guess that any discussion about "LCD2" vs "HD800" is going to become a holy war. Face it, the LCD2 has recessed treble -- you can argue until you run out of breath how much you
prefer having recessed treble, but you cannot deny the fact itself. Similarly, most people will tell you the HD800 is a little hot or bright. As to which sound you prefer, that's an individual choice.
> Oh - the HD 800 is massively better than the HD 650. But it is also really bright and sibilant and some people just like an accurate sound as opposed to what sounds like a tweeter being shoved up your butt.
In any case, the HD700 as far as we know is going to be more bright than dark, so those who prefer the LCD2 sound and hate nonrecessed treble can, as rythmdevils put it, stick a subwoofer up their [blank].
( KIDDING
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