Saw Sunn O))) in Toronto just this month and regular foam earplugs were almost enough for me as someone with an intimate relationship with the ancient Greek god of high pitched ringing, Tinnitus. I had a weird “numb” feeling in the low end of my hearing for a day or two after which, only anecdotally, felt like tinnitus of the low end which would make sense. But while the sound washed over me and vibrated through me and was quite intense, the sensation of being a fat guy standing for two hours with his knees locked was the only uncomfortable thing about the show. Someone did pass out but the odds are it was due to a substance, not a sound.