Dragon Naturally Speaking Preferred, Rev. 9
the "standard" version might be a little cheaper.
i just finished taking a class in Preferred, Rev. 7
however ... it doesn't convert a *.wav file.
you talk to the computer.
also, there's some prep. involved, where you
read words & the computer gets to know your
voice. Calibration.
just playing the voice file without calibrating
the computer to the voice ... i don't know.
Microsoft Voice Recognition Engine - another
voice interface resource.