Sri O.S.Sundar  hails from a traditional musical family of South India- Tanjore district, Tamil Nadu. Gifted with melifuluous voice, Sundar had his tutuelage in carnatic classical music from his father Sangeetha Bhushanam Sri O V Subrahmanyan, a doyen of Carnatic Music. 

Sundar has chosen the bhajan field and has participated in major and important religious and cultural functions. He has travelled widely across the country to lead many Kalyana utsavams and he is very proficient in the languages and the slokas. Bhakthi forms the essence of bhajan and good musical knowledge is an added advantage to increase the melody and bhava of a bhajan programme. His vast knowledge of carnatic music coupled with Bhasha Gyanam has given him good advantage to present any song soaked with full bhava and rasa. He has also been honoured by various religious organisations all over India. 

Sundar has recorded a video presentation of Jayadeve's Asthapathi and Radha Kalyanam for Indira Gandhi National Centre for Arts, New Delhi for the prestigious Geetha Govinda project which received wide appreciation from all over the country and abroad. 

Sundar has recently been conferred the title  'BHAJAN AMRUTHA MANI' by Kanchi Kamakoti Peetam, Kancheepuram ,  BHAGAVATHA SIROMANI by Ganananda Namma Sankeerthana Mandali, Chennai and BHAJAN BHUSHAN by Maharashtra Association, Chennai. He has also released various audio Cassettes titled GEETHA GOVINDA MAHAKAVIYAM( Jayadeva's Ashtapathi), ABHANGAVANI,(Maharasthra Abhangs) DASARAHTHI ( Songs on Lord Rama) and YADHUNANDANA ( Songs on Lord Krishna ) etc which have received wide appreciation.

He is considered one of the most sought after Bhajanist in the country today.