Wonder Wall

From your instrument of choice, your create a 20 foot tall, 10 foot long, and 5 foot thick wall of sound. Any enemy who makes contact with this wall must make a wisdom save against your spell DC. On a failed save, for every 5 foot of movement it takes 1d6 of thunder damage, for a successful save the creature takes half the damage. If they die within the wall of sound, they die of madness and take an attack of opportunity on a party enemy with in 5 feet of it.