Well, you only have two ears. The sense of directional sound is entirely caused by your ears picking up the noise at different volume, obviously. Because of the ear being just a combination of a "receiver antenna" (the external parts of it) that helps catch sounds coming from different directions, and a mono-channel microphone (the sound bones and crap in the end of the ear tunnel), one ear alone simply cannot produce directional sound.
When the sound elements are as close to the ear as they are when using headphones (practically right next to them) or when using earphones (which are actually inside the ear), two sound elements alone are enough to produce the illusion of 3D sound - and even though I say 'illusion', it's still the real thing, and it will (if the digital sound is properly created, of course, as it is in most games for example) sound like you were actually standing in the room with all the stuff happening around you.
However if the sound elements are placed further away or poorly, the illusion will diminish. Two stereo speakers right in front of you will distort the illusion, and all the echoing and such will make two stereo speakers placed to the sides of you sound poor, too.
This is where systems with more speakers step in, obviously. More speakers will simulate the circumstances you would have in real life. You will still only have two mono-channeled microphones on the both sides of your head, which will judge where the sound is coming from by comparing the received volumes of the ears.
But when using headphones, a two-element stereo system is entirely enough. You could fit in additional elements to play high- and low-pitched sounds (treble- and subwoofer elements or whatever you call them) while still keeping it a stereo system but perhaps enhancing the sound quality a bit. However, fitting a 5.1 or whatever sound system with directional elements into headphones is complete and utter bullshit, as your left ear won't be able to hear anything played by the elements in the right earphone and that defeates the purpose entirely. Just marketing crap to lure idiots into paying more.
its stereo
its like you compare premier league with 10th league
When the sound elements are as close to the ear as they are when using headphones (practically right next to them) or when using earphones (which are actually inside the ear), two sound elements alone are enough to produce the illusion of 3D sound - and even though I say 'illusion', it's still the real thing, and it will (if the digital sound is properly created, of course, as it is in most games for example) sound like you were actually standing in the room with all the stuff happening around you.
However if the sound elements are placed further away or poorly, the illusion will diminish. Two stereo speakers right in front of you will distort the illusion, and all the echoing and such will make two stereo speakers placed to the sides of you sound poor, too.
This is where systems with more speakers step in, obviously. More speakers will simulate the circumstances you would have in real life. You will still only have two mono-channeled microphones on the both sides of your head, which will judge where the sound is coming from by comparing the received volumes of the ears.
But when using headphones, a two-element stereo system is entirely enough. You could fit in additional elements to play high- and low-pitched sounds (treble- and subwoofer elements or whatever you call them) while still keeping it a stereo system but perhaps enhancing the sound quality a bit. However, fitting a 5.1 or whatever sound system with directional elements into headphones is complete and utter bullshit, as your left ear won't be able to hear anything played by the elements in the right earphone and that defeates the purpose entirely. Just marketing crap to lure idiots into paying more.
--> stereo
Here is an old one:
http://www.youtube.com/watch?v=IUDTlvagjJA
"Audio is 40% of the picture"
e: http://www.youtube.com/watch?v=8IXm6SuUigI
also great sound even at random onmotherboard soundcard and creative fatality feel that 3d sound. super.