Type of sax or singer (4)
I believe the answer is:
alto
I believe this clue is a double definition.
'type of sax' is the first definition.
(I've seen this in another clue)
'singer' is the second definition.
(type of singing voice)
(Other definitions for alto that I've seen before include "Male singer" , "Key old > male who scores high" , "Singing range" , "Woman's singing voice" , "Second of four parts (in singing)" .)