MUMBAI: Audio engineer H Sridhar has had a great part in the success of A R Rahman. Sridhar, who passed away on 1 December 2008 of a cardiac arrest, was the chief sound engineer for almost all of Rahman's films and also created the final copy of Slumdog Millionaire.

Among Sridhar's many professional credits was the fact that he engineered all songs and background scores for the renowned music director A R Rahman. Some ground-breaking films to his credit are Roja, Gentleman, Kadhalan, Thiruda Thiruda, Bombay, Duet, Mahanadi, Rangeela, Kuruthippunnal, Muthu, Indian, Minsaara Kanavu and Iruvar. He also engineered the background music score and songs for the national award winning films Kaala Paani for music director Ilaiyaraaja and Minasaara Kanavu for music director A R Rahman. Sridhar was awarded the President's Gold Medal (The National Award for Best Audiography) four times: for the film Mahanadi in 1994, Dil Se in 1999, Lagaan in 2001 and Kannathil Muththamittal in 2003.

Sources say well wishers have been remembering Sridhar's contribution to the Slumdog Millionaire success story and have been calling on his family since Monday morning.

Media reports coming from the US quote Rahman as saying, "I'm here for work. But I've to say the sudden death of my friend and my permanent sound recordist H Sridhar has been a big blow for me. He was a close friend and professional associate for twenty years. He was not just a sound recordist but also a fantastic keyboards player. He revolutionalised sound recording. I am shattered. It's a personal and professional loss. But life goes on. It has to."