Instrument mixed choirs finally confused with another (11)

I believe the answer is:

harpsichord

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'instrument' is the definition.
(harpsichord is a kind of instrument)

'mixed choirs finally confused with another' is the wordplay.
'mixed' indicates anagramming the letters.
'finally' suggests the final letters.
'with' is a charade indicator (letters next to each other).
'another' becomes 'harp' (I am not sure about this - if you are sure you should believe this answer much more).
The last letter of 'confused' is 'd'.
'choirs' is an anagram of 'sichor'.
'sichor'+'d'='sichord'
'sichord' put after 'harp' is 'HARPSICHORD'.

Can you help me to learn more?

(Another definition for harpsichord that I've seen is " Early keyboard instrument".)

I've seen this clue in The Times.

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