Extremely anaemic hideous canned music (4,5)
I believe the answer is:
acid house
'music' is the definition.
(I have seen 'loud music' mean 'acid house' so perhaps 'music' could also mean 'acid house')
'extremely anaemic hideous canned' is the wordplay.
'extremely' suggests removing the centre (only the extremes of the word are used).
'canned' indicates anagramming the letters (canned can mean drunk).
'anaemic' with its centre taken out is 'ac'.
'hideous' anagrammed gives 'idhouse'.
'ac'+'idhouse'='ACID HOUSE'
(Other definitions for acid house that I've seen before include "loud music" , "scene from the eighties?" , "youth movement" , "music? No - with 9a" , "scene from the 1980s?" .)