A self-taught musician, Sen started the band, Indian Ocean, with Late Asheem Chakravarty in 1990.

Leaving Home – the Life & Music of Indian Ocean (2010) directed by Jaideep Varma, it became the first band ever in India to be subject of a documentary.

[8] In 2012, he started touring with a new setup of artistes, called The Susmit Sen Chronicles, which included drummer Nikhil Vasudevan, bassist Anirban Ghosh, tabla player Varun Gupta and vocalists Amit Sharma and Sudhir Rikhari.

[4][11] However, he joined the Indian Ocean for a farewell tour in end 2013, thereafter he was replaced by guitarist Nikhil Rao.

[12] Early 2014 saw the release of an eponymously titled coffee table photography book on the group's history.