Torch era's dance band (9)
I believe the answer is:
orchestra
'band' is the definition.
(musical band)
'torch era's dance' is the wordplay.
'dance' indicates anagramming the letters.
'torch'+'eras'='torcheras'
'torcheras' anagrammed gives 'ORCHESTRA'.
(Other definitions for orchestra that I've seen before include "Large group of players" , "Large musical group" , "Assembly of musicians as in pit" , "eg Halle" , "Group of musical instrumentalists" .)