After four years of hard work, finally Mumbai-based writer and filmmaker Brahmanand Singh has completed "Pancham Unmixed" - a film on legendary composer R.D. Burman's life and time - and released it on DVD.

"It was in my mind for a long time. I wanted to do something definitive on him. I have tried to explore his music in the film. It was possible only by talking to people who have been around him, worked with him and also by talking to some new composers who have a fantastic interpretation of his music," Singh told.

Director Vishal Bharadwaj released the DVD Wednesday. Singer Amit Kumar and composer Shantanu Moitra were among others who were present at the event.

The two-hour long film features Pacnham's close friends, colleagues and admirers like Asha Bhosle, Gulzar, Javed Akhtar, Manna Dey, Shammi Kapoor and Rishi Kapoor and talk about the music genius.

It took Singh four years to complete the film on Pancham who revolutinised Bollywood music. Some of the memorable songs of Pancham include "O haseena zulfon wali", "Aaja aaja main hoon pyar tera", "Chura liya hai", "Khaali haath sham aayi hai," "Mera kuch samaan", "Saagar kinare" and "Ek Ladki ko dekha".

"All the people who worked with him are big names. Even though they were willing to talk, it wasn't that easy to get them at one call. I tried to get everything that I could about him. It was a huge task," said Singh.

Prominent among Singh's documentaries are "Asghari Bai" - on an octogenarian legendary dhrupad singer and "A Burden of Love" on Alzheimer's disease.

The Collectors Edition DVD pack also has a coffee table book on the composer.