I was asleep in bed when I heard what i believed to be a truck in the distance, the type of low rumble that sometimes lightly vibrates window panes. I looked at the clock and it was about 2:05 am, and my ears were surveying the truck sound as my mind began to wonder, while my body wanted sleep. where is this truck and why is it idling outside my house or at a distance was all I could think.after a few minutes of listening I realized a logical pattern to the hum, and recognized it was something else. Id like to mention I am an audio engineer by former trade and with schooling to match, with a lot of time spent playing with synthesizers and sounds all sorts of gear, Which from these interests I was hooked and had to get out of my bed to start listening some more. I was absolutely thrown for a loop and wide awake...I put my ears to the walls in my room, I put my ears to my bedroom floor, I opened the windows, left ear first, right ear next, trying to localize the source, of course this is hard or impossible with low end, , I was simply could not understand what On earth is that sound. only thing I could imagine was a teenager with a keyboard and a high powered 2000 watt sub woofer that could produce low end energy of a jet plane, with finesse and subtly. The pattern was mechanical but also slightly natural feeling in its delivery, a feeling of intelligence and purpose.For those who know audio the sound appeared to pitch up and down, in a defined pattern from about approx. 20-25hz to maybe 30-35hz, with a drone like quality, a slow ride up, a stop, then pitch down, it appeared to be reaching a area as wide as pasco county. It felt like it was coming from a source several hundred miles away and with a energy of massiveness, only due to my studies does my mind think in this way.I decided I had enough and got dressed, this whole Time I will say my hairs on my body were standing up as though in fear or something just unknown, Once outside my door I verified as best as my trained ears could do, that the sound was indeed coming from above, and was faint but also gigantic in presence, I know what it takes energetically to produce such a faint low rumble, to the un trained ear, its nothing, but this was no freggin joke. with less than a minute outside I tell you I ran back into my house in some sort of fear came over me, as though a voice was saying, go back inside. there was a eerie feeling in the air out there, add to it the air and I was starting to hear more layers to the sounds, lighter tones almost like a horn or a digereedoo. There is no reason for me to write this much but I want to see IF others have experienced this. I wont add any further comments, for those who are skeptical skip this last bit.... I consider myself psychic / empath in a humbled un-said, Un ego driven way. I sense and do receive words and images from other sides... and when I asked this night "what are you", what I gathered in response was that these sounds were a type of energetic work on the grids and lay-lines of earth and of a good nature.after a hour of listening, I put earplugs in and still heard the lows through the ear plugs of course, slightly zapped and weird ed out I fell back asleep. Ive been telling everyone I know, but nobody gives a damn, And I look like a lunatic.