Sound boost for man (6)
I believe the answer is:
philip
'man' is the definition.
'sound boost' is the wordplay.
'sound' indicates a 'sounds like' (homophone) clue.
'boost' becomes 'fillip' (I've seen this before).
'fillip' is a homophone of 'PHILIP'.
'for' is the link.
(Other definitions for philip that I've seen before include "- Larkin, English poet" , "Poet and librarian" , "Best Actor Oscar winner 2005, for 'Capote'" , "Duke of Edinburgh, say" , "Boy's name" .)