Originally Posted by Psilocybe 
Sound escaping from the cups completely is equivalent to perfect damping in the cups. Now if you mean sound getting into the cups, giving you sound cues from outside, that obviously comes with the tradeoff of, well, being able to hear those sounds, i.e. poor isolation.
Well, I make my own 5.1>stereo downmixes through a custom mixing matrix based on David Griesinger's Logic7 + some VST plugins such as Ozone4(all that through ffdshow) and movies sound just as 3D and "out of the head" as on the cd3k, once the side vents are open. If I cover them, then the sound cues cannot appear "distant" anymore to my brain: a car spanning from left to right feels like it's 10 cm away from my head top, and that's it. Once they're open, my brain is unable to guess the distance...it's just very very far.
My custom mixing matrix is using inverted phase on the rear channels and I've finetuned all the coeffs to match my HRTF and the T50RP native headstage...it took me a while, but it was well worth the trouble!
Originally Posted by Psilocybe
Aye, but the most important factor in determining the reflection of a wave from a surface is going to be the relative difference in impedance between the two. Air to plasticine will create a large reflection as it's going from low to high density. Air to paxmate dampens and scatters reflections a great deal because of the irregular surface and low density damping material.
Indeed, the reflections boucing off blutack sound really nasty, even bouncing back over Paxmate...newplast sounds far better! But you cannot beat acoustic foam for reflections, which are our biggest enemy in headphones. But IME paxmate over the baffle would get the driver to suffocate, as not enough air will be allowed to breathe in and out the driver and we do need some reflections IMHO.
The cd3k is using huge cups coz in my understanding the driver was engineered to selectively let SS sound cues bounce off them. On the cd3k, you don't have just one SS...basically every actor of the SS has one of its own, It's a baby-R10 and it's already pretty eye popping...too bad it really lacks in the deep bass department and as much as its SS is amazing, it basically sounds like a stadium reverb DSP. You are listening to the cups.
Originally Posted by Psilocybe
That's why I've always wondered why people think it's given that closed headphones will always have a smaller soundstage. I understand you're certainly more likely to get a wider feel with open cans, but it should be certainly possible to get that same feeling with closed cans I would think.
Coz they simply always will, physics at work. If the sound doesn't leak off the cups you will need a DSP if you wanna fool the brain into believing that the sound comes from very far. A true hardcore closed phone like the DT770/Pro has a ridiculously narrow 2D SS, and angling the drivers won't help either...this thing is hopeless. I believe this subject has already been discussed here on head-fi, but Huddler's search engine won't allow us to find it anyway.
Edited by leeperry - 10/8/11 at 7:42pm
