4 down
Piece
of
music
popular
gospeller
introduces
(5)
Piece of music popular gospeller introduces (5)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
Look at Piece of music — that's your definition, a largo being a slow musical movement. The answer is hiding inside "popuLAR GOspeller", with introduces signalling that the concealed letters are what you're after.