Composer having disgusted sound about contralto (4)
I believe the answer is:
bach
'composer' is the definition.
(Johann Sebastian Bach)
'disgusted sound about contralto' is the wordplay.
'disgusted sound' becomes 'bah' (I am not sure about this - if you are sure you should believe this answer much more).
'about' means one lot of letters goes inside another.
'contralto' becomes 'c' (musical abbreviation).
'bah' enclosing 'c' is 'BACH'.
'having' acts as a link.
Can you help me to learn more?
(Other definitions for bach that I've seen before include "Family of German composers" , "Brandenburg Concertos composer, d. 1750" , "musician" , "German baroque composer, d. 1750" , "musical great" .)