Tunes in transposition, mad and cold (13)

I believe the answer is:

unsentimental

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'cold' is the definition.
Both the answer and definition are adjectives. Maybe there's an association between them I don't understand?

'tunes in transposition mad' is the wordplay.
'transposition' indicates an anagram.
'mad' becomes 'mental' (mentally ill).
'tunes'+'in'='tunesin'
'tunesin' anagrammed gives 'unsenti'.
'unsenti'+'mental'='UNSENTIMENTAL'

'and' acts as a link.

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(Other definitions for unsentimental that I've seen before include "Not given to excessively tender emotions" , "Hard-headed" , "hard-nosed" , "Tough-minded" , "Eschewing tender emotions" .)

I've seen this clue in The Daily Express.

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