There's a parking ramp in Iowa City that for some reason has a loud,
harsh 60 cycle electrical hum, and some kind of blower with an out of
round squirrel cage fan that makes metallic banging aperiodic noises.
I've parked and then been transfixed by how much it sounds like things
I've heard at basement noise shows. That is arbitrary, directionless,
but also has structure.
Any time actual human musicians play, there's always an intention in
what they do, and even without traditional musical structure, it has
meaning. And if you listen to a recording more than once, things
about it become familiar. Because the human mind seeks to find meaning
in noise, the seemingly arbitrary sequence of musical events and
sounds comes to have a meaning, once your expectations are tuned into
it.
Unless you're familiar with the conventions of any musical style, it
will seem to have no apparent structure or meaning. My younger
brother, a classical violinist with no use for any sort of popular
music, came to hear me play techno, and his review was "it was very
loud and all sounded the same." Every kind of music requires a
different kind of listening. You can learn to appreciate unfamiliar
music by learning what expectations more experienced listeners have
for that style.