Yup. The main reason I use dual monitors is in recording music. One monitor for what's called a arrange page in Logic Pro which more or less looks like the main page in Garage Band. The other monitor for the mixing board window. Sometimes both monitors for the mixing board.
Also when charting music in the Mac. I can have the charting program on one monitor and iTunes on the other.
My oldest son also uses Logic Pro for his musical endeavors.