The rhapsody was then performed by Whiteman's orchestra consisting of "twenty-three musicians in the ensemble" with George Gershwin on piano. In characteristic style, Gershwin chose to partially improvise his piano solo. Consequently, the orchestra anxiously waited for Gershwin's nod which signaled the end of his piano solo and the cue for the ensemble to resume playing. As Gershwin improvised some of what he was playing, the solo piano section was not technically written until "after" the performance; hence, it is unknown exactly how the original rhapsody sounded at the premiere.