Hey, pigeonamondo, thanks for the notice here... I would never have imagined someone using it like that. If I didn't know what I was listening for, I would never guessed that the complex backdrop included this sound. But I can tell it's there since you told me. :-)
LOL. I didn't have any reference to go by. I was mostly trying to work on the idea of it seeming like the sound was mostly being transmitted through your bones -- that it's inside your head. Not sure how that *should* be done, but I got an interesting effect, whatever it is.
Thanks. There are plenty of characteristic sounds like that from our everyday world that can either be hard to capture, inconvenient to do so, or whatever, and they're hard to find. Once in a while, a notion strikes me to capture such a thing. :-)