It's funny that the music that I play the softest is rock music. Most of the time if it's on...it'll be for soft background music.
Smaller jazz stuff, such as Ella, Diana Krall and Norah Jones I tend to kick back with and relax ,(most of the time) playing around 70-78db for the main body of music.
Eva Cassiday and some of the better stuff like that

will be played any where from the 70-80 for the main body. Sometimes louder...sometimes softer. I enjoy some Gospel music at louder volumes too.
Then there's classical which will really be dictated by how I want it. This could range from a very soft quiet listening sessions, or may range up to peaks which reach over the 100db mark.
My weakness for loud music is horns. In particular the trumpet or similar variants. music is usually in the 90's and peaks up over 100db at the sitting position.
Like others have mentioned, I think distortion is really one of the keys here. 95-100db clean is much easier to listen to that 85db of crap! In fact...it really doesn't sound like it's all that loud. Which I would suppose is a problem within itself. it doesn't sound or fell like it's too loud...so you may be likely to listen at these levels for longer amount of time.
take care,
dan