According to the Academy , the award is presented to `` vocal or instrumental alternative music albums containing at least 51 % playing time of newly recorded music '' . The Academy defines `` alternative '' as a `` non-traditional '' genre that exists `` outside of the mainstream music consciousness '' .
According to the category description guide for the 52nd Grammy Awards , the award is presented to `` vocal or instrumental alternative music albums containing at least 51 % playing time of newly recorded music '' , defining `` alternative '' as a `` non-traditional '' genre that exists `` outside of the mainstream music consciousness '' .