Time two notes to be played together (5)

I believe the answer is:

tutti

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'time two' is the definition.
The definition suggests an adjective which matches the answer.

I don't understand how the rest of the clue works.

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(Other definitions for tutti that I've seen before include "With all instruments playing at once (music)" , "when everyone plays" , "With all instruments twenty four Acdn (music)" , "All performers (mus.)" , "Composer of Carmina Burana" .)

I've seen this clue in The Times.

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