Piece of music over before spoken introduction to evensong (9)
I believe the answer is:
pastorale
'piece of music' is the definition.
(I know that pastorale is a type of piece of music)
'over before spoken introduction to evensong' is the wordplay.
'over' becomes 'past' (I've seen this before).
'before' says to put letters next to each other.
'spoken' becomes 'oral' (similar in meaning).
'introduction to' says to take the initial letters.
The first letter of 'evensong' is 'e'.
'past'+'oral'+'e'='PASTORALE'
(Other definitions for pastorale that I've seen before include "What may feature actors" , "Musical work" , "play about 2 [ARCADIA]?" , "Noted work" , "Some country music" .)