The big band sound dominated for most of the decade, although bebop emerged in the late 1940s as a style of jazz in great contrast to the music of the big bands. It featured a small group of musicians rather than the 10 or more associated with the big bands. The smaller size allowed more solo opportunities for the players. The music itself was characterized by more complex melodies and chord progressions, as well as more emphasis on the role the rhythm section. Furthermore, phrases within the music were often irregular in length, making bebop interesting to listen to, but in contrast to music of the big bands.