A small room — it's awkward for the player of a large instrument (7)
I believe the answer is:
cellist
'player of a large instrument' is the definition.
'cellist' can be an answer for 'player' (cellist is a kind of player). I'm not certain of the 'of a large instrument' bit.
'a small room it's awkward' is the wordplay.
'a small room' becomes 'cell' (eg a prison cell).
'awkward' is an anagram indicator.
'its' with letters rearranged gives 'ist'.
'cell'+'ist'='CELLIST'
'for the' acts as a link.
Can you help me to learn more?
(Other definitions for cellist that I've seen before include "String player" , "Du Pre or Lloyd Weber" , "Musician in string section" , "Lloyd Webber?" , "E.g. Casals, du Pre" .)