I took the bar exam 15 years ago in New York, and it was my experience that I wanted music to soothe and relax me leading up to the exam, not to psyche me up. I think staying calm and focused is helpful the days of the exam, so I listened to classical on the morning drives to the exam and found that to be quite helpful. At the time my knowledge of classical music was quite limited (it's marginally better now) and I preferred Wynton Marsalis playing the Hayden trumpet concertos. Good luck on the exam!