Melody has a certain way that it projects back to you. It triggers certain nerves in your body and certain instincts that normally wouldn't be triggered by a normal voice.
While it is never safe to affirm that the future of Physical Science has no marvels in store even more astonishing than those of the past, it seems probable that most of the grand underlying principles have been firmly established and that further advances are to be sought chiefly in the rigorous application of these principles to all the phenomena which come under our notice.