That’s actually a pretty solid idea. The low‑end rumble and hiss on a subway run can be turned into a gritty bass line if you slice it and pitch‑shift a bit. Layer a little delay on the hiss so it loops into a low‑frequency groove, then line it up with a kick. Keep the pitch tight, otherwise it’ll just sound chaotic. Give it a try, it could turn into a fresh glitch‑city vibe.