A tribute to the cinematic legend, the song, written by Navin Jha and composed by band's vocalist Charu Moohan, is called "Amitabh uncle".
Produced by AB Fans Foundation, an NGO aimed to promote new talent in music, film and literature, the song is part of the album "Thank you Mumbai", which is the band's way of thanking the city and the people who make it what it is.
"Amitabh uncle" is the second song to be released and will be available online later this month. The song depicts the journey taken by a fan from his hometown to see his childhood hero.
A CD of the song has been sent to the 69-year-old actor.
"Amitabhji knows about this fan foundation, but he is not directly involved in it. I had sent him the audio CD of the song and also met him after that," Shivananda Chand, founder, AB Fans Foundation, said in a statement.
Dedh iinch upar comprises seven members -- two vocalists Charu Moohan and Anubbhav Sumann, keyboard and trumpet player Robin, bassist Steve, lead guitarist Deepak Sinha, drummer Abhishek and percussionists Atul Pandey and Atul Dutt (who is also manager for the band).