Hello, I am trying to figure out if I can replace the audio speaker from a pair of "cheap" ear bud speakers from a mp3 player with a piezo so that when the music is playing there is produced a vibration instead of an audio signal? Is this possible? would the small battery used in a small ipod shuffle-like mp3 player be enough to "cause" vibrations? I have an autistic son who I believe will benefit from the stimulation of the vibrations across the skin at the boney aspect of the mastoid bone (boney part of the skull that is just behind the ear). This is a trial and error experiment. He constantly is making noises. It appears that he needs more stimulation but we need to differentiate between the stimulation of hearing and speach. Thanks for any replies.