"The rumble was made up of several "notes" or components, and it approximated a minor key. Really hard to put your finger on, but it was there, and ominous, and it was made up of several components."
If it "approximated" a minor key I assume you have had a spectrum analiser on it and would be able to tell exactly which notes were being played! This would mean that it was NOT difficult to put your finger on and indeed you had done exactly that. So what exactly were the notes? And if you are talking about subliminal messages they must have changed!Cut out all the psudo psycobabble and give some hard information...... then be prepaired to be rebutted. Just for the record I have heard of nothing that could do anything more than to make you feel unwell/scared or anxious and those frequencies are 2 to 4Hz!