Megastar Amitabh Bachchan, who has recorded a song for "Kaun Banega Crorepati (KBC) 6" with composer duo Salim-Sulaiman, says he had butterflies in his stomach while recording it.

KBC will go on air Sep 7 on Sony and the mock rehearsals for the game show continues, wrote Big B who will host the show.

"...The crowning glory is the session at Salim-Sulaiman's recording studio later at night to record a song for KBC, and my extreme hesitation in doing so for it is a moment filled with immense self consciousness," the 69-year old posted on his blog srbachchan.tumblr.com.

"I think it becomes relevant and important to be in a state of complete comfort before performing any creative act. It is for me. And when the environ is not conducive, the soul is absent. I have not done much with Salim-Sulaiman, and that always comes in the way when they are in charge," he wrote.

Big B confessed that he often opts for composer Aadesh Shrivastava because they have had several jamming sessions and that he also enjoys a rapport with Vishal-Shekhar.

"... but Salim-Sulaiman, made me nervous and anxious and yes, the butterflies which have now found permanent residence within my intestines.

However, this must be said, the experience tonight has been most rewarding and fruitful. Not in the rendering of my song, but just in the required adjustment of being at ease there within their equipments and computers and instruments and with those that operate them!

"My singing as always is awful, their sound is awesome, and there shall be several sittings before they shall decide whether I have passed muster...," he wrote.