Rajamanickam Pillai was born at Alangudi near Nidamangalam, of Kamalathammal of Isai Velalar sect. The mother was very much interested in developing the musical talents of her son. He had training in vocal music under Nagaswaram Kandaswami Pillai, Tiruvisanallur Pallavi Narayanaswami Ayyar and Pandanallur Chinnaswami Pillai and violin under Tirukodikaval Ramaswami Ayyar for four years.
He stopped vocal music under advice as violin suited his genius. The disciple was devoted to his guru and the master too had not spared the rod. In his musical advancement, Rajamanickam had the advice of Kumbakonam Flute Nagaraja Rao and Umayalpuram Swaminatha Ayyar, two senior vidwans. He had played for all top artistes.
He would play for juniors also. Rajamanickam Pillai was honoured at the Courts of Ramnad, Cochin, Ettayapuram, Travancore and Mysore. He was Asthana Vidwan at Travancore in 1940 and at Ettayapuram in 1942.
He had been the recipient of Sangita Natak Academy Award in 1959, Isai Perarignar from the Tamil Isai Sangham and Sangita Kalanidhi from the Music Academy in 1948. Once he got an elephant as a gift and donated it to Sri Adi Kumbheswara Temple, Kumbakonam. His disciples included M.M.Dandapani Desikar and Govindaraja Pillai.