Listen to any FM station or music channel on television and you will frequently hear the soulful title track Kabhi Alvida Naa Kehna from director Karan Johar's recently released film of the same name being sung by Sonu Nigam.

Ask some one to name a top playback singer of today, and once again you'll hear Sonu Nigam.

Johar has admitted that he cannot imagine or desire anyone except Shah Rukh Khan for the lead role in his films. The same holds true of Sonu and Karan's desire for him to sing title-tracks of his films.

Kabhi Khushi Khabie Gham, Kal Ho Naa Ho and Kabhi Alvida Naa Kehna, the title tracks of all these films were recorded by Sonu and all of them chartbusters.

"I always choose Sonu for all my projects because he has the best voice in the industry today," said Johar.

Critics agree, they feel Sonu possesses a special ability to touch the listeners' soul. Shankar, Ehsaan and Loy, music directors of KANK echo this sentiment.

"For us I think Sonu is the best singer in the industry and the way he has delivered the title song and Tumhi dekho naa, it shows his sincerity. He is a wonderful singer and none of our project is complete without him."

This only serves to make his announcement of semi-retirement even more of a disappointment.