how to change pitch of sound without changing speed? wav file

Is it possible to change the pitch of a .wav or similar recorded sample without changing the speed of it's playback?

And if so, can it be done in such a way that it's possible to know what pitch is going to be produced. eg, play a musical scale accurately

Maybe it can help you
Check it:

audio.pitch = 0.1f

http://unity3d.com/support/documentation/ScriptReference/AudioSource-pitch.html