I've wondered about this myself, for 2/3 of my time on CoX I have had a creative soundworks 5.1 surround system even though now I play solely on stereo headphones.
With the 16-bit soundcard I presume enable 3D sound takes certain ambient SFX and location based SFX and channels them to the appropriate speaker in relation to where you are facing - at least that is how it felt when I used it. I am not sure the options '3D sound' is a true 3D software/hardware translation (aka
olby 5.1/THX/Dolby Digital) but rather a pseudo-3D.
It does a dopler shift effect. Move past (or rotate) near a glowie and you can hear the pitch change.
I really should do something about this signature.
Hmm - Thanks Praf. That confirms what I think I was hearing. That and a greater distinction in volume between events that are taking place close to the toon and further away...
Or maybe I'm imagining that second bit. 
Ever wondered how our costumes stay so clean and shiny given everything we put them through?
Then you need to try out Spandex Crisis (Arc ID 32943)
OK, so I've activated this option in the Graphics and Audio settings menu... and ... I'm really not sure what's actually different. Does anyone know what this option really does?
Cheers
Drag
Ever wondered how our costumes stay so clean and shiny given everything we put them through?
Then you need to try out Spandex Crisis (Arc ID 32943)