Sixties pop sounds beset my ear deplorably (6,4)

I believe the answer is:

mersey beat

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'sixties pop sounds' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'beset my ear deplorably' is the wordplay.
'deplorably' is an anagram indicator.
'beset'+'my'+'ear'='besetmyear'
'besetmyear' with letters rearranged gives 'MERSEY BEAT'.

Can you help me to learn more?

(Another definition for mersey beat that I've seen is " Liverpool sound in pop".)

I've seen this clue in The Telegraph.

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