Eight performers (5)
I believe the answer is:
octet
'eight performers' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for octet that I've seen before include "Chamber ensemble, a Mendelssohn favourite" , "A group of eight, may be singers" , "Piece for eight players" , "Played" , "A group of eight instruments or voices" .)