The recorder is light (5)
I believe the answer is:
taper
This clue is a double definition.
'the recorder' is the first definition.
(I've seen this before)
'is light' is the second definition.
(I've seen this before)
(Other definitions for taper that I've seen before include "Gradually reduce - spill" , "Become narrow" , "Wax light; narrow" , "See the light" , "Convex shape that narrows toward a point" .)