Hi there…
I have a mp3 sound data 7 minutes long about, is supposed to work with TV, news comments.
Since the sound’s source is in only one point (TV), i must to use 3d sound system. then when i´m far, the sound volume gets low, near, gets high…
is 3d sound applied automatically by dragging the mp3 source to an object ? or do i must to make something special …
thank you…
The sound source needs be mono in order for it to be a 3d sound source.
the source is already mono…
does unity detect 3d sound automatically ?
Not in Unity 2.6! 
well!, but, how do i make it? 
I don’t understand why you are asking this. You can either look in the documentation or just turn Unity on to find out that this works just fine. I mean, Unity is (partially) a 3D game engine. Why would you think this wouldn’t work? Why are you making a question on the forum?
simple!, because i tried to put the sound to an object is located even in the same place if you move far, the sound reproduces with the same volume, and can´t find an option saying “activate 3D sound for this”, i looked to find it either my sound is not working like i´m expecting.
Maybe my scenery is not big enough to appreciate it…
Edited:
Maybe my scenery is not big enough to appreciate it… (yes, that was).