Mac OS X Hints posted this article about the “Perfect” Itunes Equalizer Setting.
Open the equalizer, and from the pop-up menu, select “Make Preset.” Call it “Perfect,” because it is, and set the following levels, from left to right (skip the Preamp section):
db +3, +6, +9, +7, +6, +5, +7, +9, +11, +8 db
Okay, he acknowledges that there’s no such thing as a “perfect” setting, but that this is the best one he has found. It doesn’t say what type of music this works for though.
In regards to hip hop, it’s pretty decent for some songs and unbearable for songs like Jay-z’s Show Me What You Got where the horns are just blaring in your ears if you have headphones on. It’s better than flat for most songs, but just be aware that there’s no such thing as a preset you can just turn on that works for every song. Each song, genre, speaker set up is different and must be worked with differently.