That's Shoegazing pretty much...
Most of it is extremely loud, like for example in My Bloody Valentine concerts they give out earplugs to everyone to avoid the crowd getting tinnitus. The style of music is made by heavy reverb, and guitar delay which gives it it's constant droning sound. It's possibly more heavier than most metal is.
Noise Rock, and Noise Pop, the genres Shoegazing originated from also share the similar traits as Shoegazing albeit with less ethereal like vocals.
Seriously, no matter how much I love this music, i wouldn't want to listen to these bands full blast for hours at a time.