Sound of disapproval - it upset all performers (5)
I believe the answer is:
tutti
'sound of disapproval it upset all performers' is the definition.
I can't judge whether this defines the answer.
'sound of disapproval it upset' is the wordplay.
'sound of disapproval' becomes 'tut' (I've seen this in another clue).
'upset' says the letters should be written backwards.
'it' written backwards gives 'ti'.
'tut'+'ti'='TUTTI'
Can you help me to learn more?
(Other definitions for tutti that I've seen before include "All instruments must play" , "when everyone plays" , "(Musically) performed by all instruments" , "- - -frutti" , "(Of an orchestra) all to play together" .)