Large part of the effect is depending on your ear anatomy. If it's not compatible, there's not much you can do, highs can sound funny like you say, speaker positions vary etc. Dolby Headphone etc use a generic HRTF profile which match "most people decendly". OOYH currently has one, Darins. So it's hit and miss. DSpeaker Headspeaker is probably still the only thing on the market offering dozens of HRTF profiles to try to match on. Realiser is the only one customing your ears exactly.
Well here's something new (to me at least) and interesting.
Today I got out a NOS dac that I've been intending to sell (Scott Nixon Tube Dac 2.2), just to try something different, and boy did I get something different.
In the other setup I'd been trying out I'd become quite discouraged, I could not even get the levels of the speaker setups near the level of the bypass, never mind get good sound from OOYH. The bypass sound was much lower than the preset's level.
With this new setup, the bypass sound was actually louder. That I could deal with, because I could turn it down to match the preset's levels. Also, more significantly, the speaker choices sounded much better, at times. The weird thing is the "at times." Everything seemed to affect the sound. Like what you might ask. Well the dac, but also the headphones and the recording.
I need to experiment with this much more before I form any definite conclusions but here are some for instances, for starters.
I was listening to one track and it came across ear scorchingly bright (Audio Technica 900s), switched to Fostex T50Rp--slightly modded, and the sound was almost dull.
Now granted the AT's are a bit on the bright side, but nothing like this, and the Fostex are not dull. Besides only that one track came across like that. Other tracks sounded fine on the AT's.
I also have the Sennheiser Px100s. Light over the ear phones, inexpensive but very good for their price. Some tracks sounded horrible on them, others fine.
Nothing ever sounds horrible on any of my headphones, not everything sounds great, but when it sounds horrible it sounds horrible on all, because the recording sucks.
So what I'm really saying (and maybe this has to do with ear shape vs. headphone cup shape) but the variation of quality of sound that has come through my phones when coming from the OOYH driver is immense, from very good, where indeed the sound opens up and the phasing effects and hi freq effects are very light/possibly non existent to godawful. And this variation can come from the same preset depending on the recording and/or headphones. It's really bewildering.
I will have to try to study this a lot more--if I can muster the patience, to see if I can discern a pattern. I shall report back.
By the way, in earlier posts several people complained about the lack of bass. There was no lack of bass in anything I was listening to. Even the AT's which are known to appear to be a bit bass shy, were not.
-Chris