Beloved: sound of instrument if given love? (4)

I believe the answer is:

beau

'beloved' is the definition.
(beau can mean a male lover)

I can't explain the remainder of the clue.

(Other definitions for beau that I've seen before include "Handsome man" , "French boyfriend" , "One loving" , "An old boy friend or dandy" , "Male lover of a girl or young woman" .)

I've seen this clue in The Guardian.

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