Drums (3-4)
'drums' is the definition.
(type of drums)
This is the entire clue.
(Other definitions for timpani that I've seen before include "Those beaten" , "Percussion section" , "Main pit (anag) - drums" , "Features of kitchen" , "> kitchen equipment?" .)
'drums' is the definition.
(I've seen this before)
This is all the clue.