Ad filmmaker-turned-lyricist Prasoon Joshi has another role to play - he has turned composer for Prakash Jha's "Aarakshan", and says it was a wonderful experience.

Joshi, who has written four songs for the movie, has composed one song named "Kaun si dor" for the album, which has otherwise been composed by popular trio Shankar-Ehsaan-Loy.

Narrating how he took to composing the song, Joshi said: "'Kaun si dor' is a wonderful song. The thought was to centre it on a philosophical level but in a common man's understanding. Often whilst writing, a composition comes up in my head and while writing this song, the composition just flowed through my mind."

When Joshi bounced the idea to Jha and Shankar Mahadevan, "they loved it", he says.

"Shankar was graceful enough to keep this as part of the album and I am genuinely thankful. 'Kaun si Dor' comes at a poignant juncture in the film and I am looking forward to the music of this film, " he said in a press statement.

The rendition for Joshi's composition has been done by classical vocalist Chunnulal Misra.

Joshi, a well-known advertising professional, has a lineage when it comes to music, too. Both his parents are classically trained and he himself is trained in Hindustani classical vocals. He has composed and sung a few of his ad jingles as well in the past.

Working with Jha has been "wonderful", says Joshi.

"Prakash Jha is a remarkable director, who does thoroughly researched films which are very unique, have strong narrative and original plots across different genres, piloting fresh trails, and commercially viable. He always encourages fresh and unique ideas. It indeed was an wonderful experience to work with him, " he said.

"Aarakshan" features Amitabh Bachchan, Saif Ali Khan, Manoj Bajpayee and Deepika Padukone. The movie, based on caste-based reservations in Indian society, will release in August.