Some information on etude, a musical composition (5)
I believe the answer is:
nonet
'a musical composition' is the definition.
(I've seen this before)
'some information on etude' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'NONET' is hidden within 'information on etude'.
(Other definitions for nonet that I've seen before include "Musical group" , "Piece for nine players" , "Piece for nine payers" , "Band's" , "Composition for nine players" .)