3D sound

Virtual haircut ..
really unbelievable .... pinch yourself twice before you believe it ...
headphone is a must

click here or here ....

well there are two out of the box stuff i can think of ...
the concept of 3D sound is out of the box itself ... i wonder how is it done
more examples of 3D sounds can be found here ...
probably the right technical jargon for it is ... audio illusion ..

ok the technology is out of box ..
what else ??
its application to a virtual haircut ... correct ??