Strange piano American noise (6)
I believe the answer is:
rumpus
'noise' is the definition.
(thesaurus)
'strange piano american' is the wordplay.
'strange' becomes 'rum' (synonyms).
'piano' becomes 'p' (musical abbreviation).
'american' becomes 'us' (abbreviation for United States).
'rum'+'p'+'us'='RUMPUS'
(Other definitions for rumpus that I've seen before include "Making a fuss" , "Row" , "Noisy brawl" , "'Commotion, din (6)'" , "Noisy disturbance" .)