Whole range (1,2,1)
'whole range' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for gamut that I've seen before include "The whole range or scope of anything" , "Entire scale" , "Full (emotional) range" , "Whole range (from A to Z)" , "Full extent" .)
(Other definitions for a to z that I've seen before include "Alphabet" , "Gazetteer" .)