Beat with energy in musical piece (5)
I believe the answer is:
tango
'musical piece' is the definition.
(I've seen this before)
'beat with energy' is the wordplay.
'beat' becomes 'tan' (I've seen this before).
'with' is a charade indicator (letters next to each other).
'energy' becomes 'go' (I've seen this in other clues).
'tan'+'go'='TANGO'
'in' is the link.
(Other definitions for tango that I've seen before include "Dance originally from Buenos Aires" , "reputedly takes two" , "Last - in Paris (film)" , "Argentine dance" , "Dance music" .)