Composer and men in small room beginning to improvise (7)
I believe the answer is:
corelli
'composer' is the definition.
(Arcangelo Corelli)
'men in small room beginning to improvise' is the wordplay.
'men' becomes 'or' (I've seen this in other clues).
'in' is an insertion indicator.
'small room' becomes 'cell' (I've seen this before).
'beginning to' says to take the initial letters.
The initial letter of 'improvise' is 'i'.
'or' put within 'cell' is 'corell'.
'corell'+'i'='CORELLI'
'and' is the link.
(Other definitions for corelli that I've seen before include "Arcangelo --, Italian baroque composer" , "Marie - - , romantic 17" , "Arcangelo, seventeenth to eighteenth century Italian composer, violinist" , "A mandolin-playing Captain" , "Captain -'s Mandolin (de Bernires)" .)