As part of the action you use to make a ranged weapon attack, you cause the ammunition you fired to explode and shatter.  Each creature within 30 ft. of it must make a Constitution saving throw, taking (5d6) thunder damage on a failed save, or half as much damage on a successful one.  The original target is affected by this thunder damage, but makes no saving throw and takes full damage.  Objects and structures take maximum damage from this effect.  A creature that fails its save against the thunder damage (including the original target that makes no save) is stunned until the end of its next turn.  Creatures made out of inorganic material have disadvantage on the saving throw against this thunder damage.   

Success or fail, a creature that takes thunder damage from this spell is deafened for 1 minute.  It can make a Constitution saving throw at the end of its turns, ending the deafened condition on a success.          

At Higher Levels.  When you cast this spell using a 4th level spell slot or higher, the thunder damage increases by 1d6 for each spell slot level above 3rd.