Condensed tune possibly piped (10,3)

I believe the answer is:

compressed air

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'condensed tune' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for compressed air that I've seen before include "Tyre filler" , "that's piped" , "Filler for tyres" , "Something provided on garage forecourt" .)

I've seen this clue in The Globe and Mail.

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