Why can bands play for hours often utilizing different instruments without ever looking at sheet music, but orchestra musicians always read from sheet music?

Question

I saw a clip where a pianist was playing and someone was turning her pages for her, but they fumbled and dropped the sheet music. The pianist kept on playing, but it got me wondering why have the sheet music if she knows the song anyway. Do they really need it? Why can’t they just learn the songs like all bands do?

In: 5311

Answer 1

Different genres have different standards on staying true to the written music. Rock and pop generally don’t care as much as long as it sounds close enough. In jazz, deviation is often encouraged. In orchestral settings, it’s expected to stay true to the original.

Pianists and orchestral musicians will generally have the music memorized, but it’s still helpful to have sheet music available as a backup just in case. It’s normalized to have sheet music there.