I just put a set of Anakee 3s on my 800XC. These tires are LOUD at 55 - 60MPH. On my first ride it sounded like a turbine was spinning up around 50MPH and the sound just got louder and louder up to 58MPH and then slowly subsided. Wow.
I wear ear plugs all of the time and they did not help. The volume has decreased somewhat with more wear but my guess is that they will always make some noise. I should have gotten another set of the Scorpions.
I've been a big Michelin tire fan for my cars and bikes but these do not make the grade. I hope they wear out quick!