Respectable - kind of piano (7)
I believe the answer is:
upright
I believe this clue is a double definition.
'respectable' is the first definition.
(thesaurus)
'kind of piano' is the second definition.
(I know that upright is a type of forte-piano)
(Other definitions for upright that I've seen before include "Vertical, erect" , "Standing vertically - post" , "with principle" , "Vertically honourable?" , "Key item" .)