he is widely considered and ranked as one of the greatest vocalists in metal history, with praise given to his unusual delivery and his wide vocal range. serj tankian is currently listed as one of the "top 100 heavy metal vocalists" by "hit parader", ranked at number 26. a study conducted by vvn music found tankian to possess a moderately-high and diverse vocal range, not only in metal, but in all of popular music, with a range of 4.2 octaves. this range is comparable to rob halford, elvis presley, freddie mercury, hansi kürsch, chris cornell and steven tyler (range of four octaves and one note).