As I understood the article at the time, the researcher was using the words 'tone' and 'pitch' arbitrarily to describe a relationship he'd discovered. In the normal world of mechanically generated sound waves, tone and pitch always vary in parallel and appear to be almost the same thing. The researcher discovered a way to create computer generated sounds in which tone and pitch moved in opposing directions. Since I only read the article and never got to hear the examples, this is the best I can do. This isn't something you would ordinarily call music. The article also mentioned that the man was an amateur composer and had used an hour long descending tone as ambience in a play about a man going mad. They had to drop it after a few performances because it was driving every one up the wall. The article (if I haven't gone mad myself) would have appeared some time between 1960 and 1970, I think. To the best of my recollection, the article was not in the April edition.

As for the 'breaking glass' effect, that wasn't explained.

When I finally had some time and money to call my own, I spend most of a day in the research/reference section of the local library trying to track it down. Needless to say...