Further thoughts on 5Hz signals … even if no one mixed in a 5Hz signal, there could be interference between two frequencies that results in a 5Hz undertone. When two frequencies are mixed, two additional frequencies are created, one at the sum of the two frequencies, one at the difference. These new frequencies also interact with each other and the original two and create even more. The way this all plays out can create pleasant chords or create something rather unpleasant. In any case, if the two fundamental tones happen to be 37Hz and 42Hz, then there will be a 5Hz component to the mix. If one can observe the driver of a subwoofer under such conditions, and if the sub is driven hard, you might see what appears to be some very low frequency, awkward driver movements.

Speaking of Switched on Bach, I remember liking it very much. The only ‘negative press’ I heard it receive was from the professor of a ‘Physics of Musical Sound’ course I took in college. He generally abhorred sound waves originating in non-classical ways, without the oscillation of physical materials. In other words, to be ‘good and genuine,’ it had to be apart from electronic synthesis. I’ll give him this much: good, natural sound is amazing in both effect and nuance.