Concert with huge pieces of publicity (6)

I believe the answer is:

promos

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'pieces of publicity' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'concert with huge' is the wordplay.
'concert' becomes 'prom' (abbreviation for promenade concert).
'with' is a charade indicator (letters next to each other).
'huge' becomes 'os' (abbreviation for outsize).
'prom'+'os'='PROMOS'

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I've seen this clue in The Guardian.

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