Jerry, the original book "Sound Therapy for the Walkman" by Patricia Joudry, answers your question related to yesterday's entry "08/17/06 - With reference to the hearing article above", on rejuvenation the ear, and health in general.
Get the updated book here: http://www.soundtherapyinternational.com/ The original book came with a couple of typed pages saying that digital audio, from CD's, was bad for your health, and they they where going to come out with a book elaborating on that. I have not seen it if the did. Also in the area of sound related to "08/17/06 - What? Test your hearing with a few mp3 samples:". Some teenagers have created high frequency ring tones for their cell phones that "old fogies" can not hear. -- http://www.softwaresafety.net/ http://www.designer-iii.com/ http://www.unusualresearch.com/
