premise: In the End contains the instrument piano within its main melody.
hypothesis: Accompaniment . Alternatively , the accompaniment to a vocal melody or instrumental solo can be provided by a musical ensemble , ranging in size from a duo ( e.g. , cello and piano ; guitar and double bass ; synthesizer and percussion ) ; a trio ( e.g. , a rock power trio of electric guitar , electric bass and drum kit ; an organ trio ) ; a quartet ( e.g. , a string quartet in Classical music can accompany a solo singer ; a rock band or rhythm section in rock and pop ; a jazz quartet in jazz ) ; all the way to larger ensembles , such as concert bands , Big Bands ( in jazz ) , pit orchestras in musical theatre ; and orchestras , which , in addition to playing symphonies , can also provide accompaniment to a concerto solo instrumentalist or to solo singers in opera . In the End . `` In the End '' received positive reviews by music critics , with most reviewers complimenting the song 's signature piano riff , as well as noting rapper Mike Shinoda 's vocal prominence in the song . Vocal harmony is a style of vocal music in which a consonant note or notes are simultaneously sung as a main melody in a predominantly homophonic texture .