Ask Sananda 19: About Sound

Why does humming feel so good? Even when I’m not actually making sound, just humming in my head silently, it seems to be very soothing for my body and emotions. Are you able to tell me why? Can you say more about the properties of sound and how beneficial they might be to us? Finally, I read once a theory that the great pyramids in Egypt were assembled through sound – is this true?