Diagram or design for old sound system (9)
I believe the answer is:
radiogram
'old sound system' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe you can see an association between them that I can't see?
'diagram or design' is the wordplay.
'design' is an anagram indicator.
'diagram'+'or'='diagramor'
'diagramor' anagrammed gives 'RADIOGRAM'.
'for' is the link.
Can you help me to learn more?
(Other definitions for radiogram that I've seen before include "Message once sent by wireless telegraphy" , "old-fashioned audio equipment" , "Old combined record player and radio" , "old entertainment centre?" .)