Instruments producing pair of notes (11)
I believe the answer is:
pianofortes
'instruments' is the definition.
(pianoforte is a kind of instrument)
'producing pair of notes' is the wordplay.
'producing' indicates anagramming the letters.
'pair'+'of'+'notes'='pairofnotes'
'pairofnotes' anagrammed gives 'PIANOFORTES'.
(Another definition for pianofortes that I've seen is " Keyboard instruments".)
I've seen this clue in the Best For Puzzles.
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