"I am very happy to have used the classic waltz, lyrical, lilting music and duets for 'PK'," he told PTI during his visit here for the launch of his debut book in English 'On the Wings of Music'.
"My use of music in 'PK' goes with my belief that a rich baritone like Nat King Cole has an eternal appeal," said Shantanu, who has previously composed music for 'Parineeta', 'Lager Raho Munnabhai', 'Hazaron Khwahishen Aisi', 'Madras Cafe' and '3 Idiots'.
'PK' has been directed by Raj Kumar Hirani and also stars Anushka Sharma, Sanjay Dutt and Sushant Singh Rajput. It is scheduled to be released on December 19.