I have always thought my new sound system sounded a bit off, when I play music for example; the sub produces strange low rumbling sounds, even if the music has no low frequencies. I discovered why; by playing 4000hz against 3950hz it produces 50hz. The SUB produces 50hz, I repeat; the SUBWOOFER is playing combination tones. Why is my sub breaking the laws of physics? 2 dissonant tones of 4000hz does not actually produce a new low tone in reality. I suspect it's probably some sort of weird amplifier thing, or something going wack in the band seperator. Any help is appreciated.
It's called "beating". Google it. It is actually going according to the laws of physics.
I know what beating is. The resultant frequency difference between 4000 and 3950 manifests as amplitude modulation, not as a non-existant distortion tone that then plays through my subwoofer. I don't think you completely understood the problem.