Heart so affected sounds can be heard within it (7)
I believe the answer is:
earshot
'sounds can be heard within it' is the definition.
I can't judge whether this definition defines the answer.
'heart so affected' is the wordplay.
'affected' indicates an anagram.
'heart'+'so'='heartso'
'heartso' is an anagram of 'EARSHOT'.
Can you help me to learn more?
(Other definitions for earshot that I've seen before include "catching distance?" , "Hearing distance" , "Distance within which a sound can be heard" , "Range over which one may hear or be heard" , "Hot ears (anag.)" .)