Instrument with hot amp ends covering Queen (4)
I believe the answer is:
harp
'instrument' is the definition.
(harp is a kind of instrument)
'hot amp ends covering queen' is the wordplay.
'hot' becomes 'h'.
'ends' suggests removing the centre.
'covering' indicates putting letters inside.
'queen' becomes 'r' (r is abbreviation regina. e.g. in ER ).
'amp' with its middle removed is 'ap'.
'ap' enclosing 'r' is 'arp'.
'h'+'arp'='HARP'
'with' acts as a link.
(Other definitions for harp that I've seen before include "Musical symbol" , "Large plucked instrument" , "Keep on about" , "Stick to one theme" , "Talk tiresomely using upright musical instrument" .)