So I took my own pulse...and simultaneously, I ran my head through THE tune. My tune. And...yep. I found, much to my amusement, a perfect match. Without conscious effort, they were perfectly synchronized, heartbeat and tune. My tune, THE tune, got its original tempo from me. Quite literally, it is a tune about me, because it's taken directly from me.
Worth noting is that, interestingly enough, it's my standing heartbeat rather than a sitting/lying down pulse (the two are not the same; my heartbeat slows down significantly upon sitting/lying down), but I've checked it both ways now, multiple times, and confirmed: the pulse matches the music which matches the pulse.
In hindsight...this makes sense, since I also found out through experimenting that I have a tendency to walk to the rhythm of my heartbeat. No joke. I was taking my pulse, and realized without trying, my steps were matching the rhythm. Why is this relevant? Because THE tune first manifested, the first time I started thinking about it...while walking. Specifically, at college, walking from my car to wherever I plopped down. I began running my head through a tune about then, probably two years ago by now (maybe not that long, but certainly over a year since THE tune predates my blog), and if I got the tune from my footsteps and my footsteps come from my pulse, I indirectly got the tune from my heartbeat.
So while I can't say for sure that this tune is my soul, I now CAN say for a fact that at least it's my heart!