Hearing perhaps about us quietly creates tension (8)
I believe the answer is:
suspense
'tension' is the definition.
(thesaurus)
'hearing perhaps about us quietly' is the wordplay.
'hearing perhaps' becomes 'sense' (hearing is a kind of sense**).
'about' is an insertion indicator.
'quietly' becomes 'p' (p for piano and quiet).
'us'+'p'='usp'
'sense' enclosing 'usp' is 'SUSPENSE'.
'creates' is the link.
(Other definitions for suspense that I've seen before include "State of uncertainty or excitement" , "Uneasy uncertainty" , "Tense uncertainty" , "Uncertainty and apprehension about what's going to happen" , "Tense expectation" .)