Yes MarkM these videos you posted are very beautiful and awe inspiring, however I find the most intriguing aspects to this new science when interference patterns are studied. Some examples of interference patterns in Cymatics can be seen in this video.
When I think about these concepts it reveals to me that it is not any one instrument in the band that is of more importance than any other. In fact it is the contrast or interference of the two or more waves of sound that make the overall essence of the music they are playing. This would also mean that it does not matter exactly what genre of music it is you listen to, what matters is how well those musicians harmonize and contrast with one another. This being said I believe much of the Metal genre is in extreme contrast, however there are few Metal Bands that harmonize using those beats and tones common in Metal. Easy listening music may be easier for the musicians to harmonize within, thus making it easier to listen to.
I think it's the ability of the musicians to create the ambiance of sound which is important, rater than the types of sound they use.
This also can lead to how our music is judged. Such as we start with the base of the drums, then the base guitar adds to the beat slightly contrasting it, then the rhythm guitar includes even more contrast, and the lead guitar add more and finally the singer tops the contrast with them all. Creating a sound, and allowing us as listeners to be moved by the harmonies we hear.
Now and then when I see her face
She takes me away to that special place
And if I'd stare too long
I'd probably break down and cry
Gnothi Seauton (know thyself)