What a judge has, one with a deep voice (7)

I believe the answer is:

robeson

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'voice' is the definition.
Both the answer and definition are singular nouns.
Maybe they are linked in a way I don't understand?

I can't explain the remainder of the clue.

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(Other definitions for robeson that I've seen before include "Paul ......., great American bass singer and actor (" , "Paul -. US bass singer and actor" .)

I've seen this clue in The Times.

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