Ranganathan began performing professionally in 1938. At the California Institute of the Arts and Wesleyan University he taught many non-Indians Carnatic music, including Robert E. Brown, John Bergamo, Jon B. Higgins, Douglas Knight, David Nelson, Royal Hartigan, David Moss, Glenn "Rusty" Gillette, and Craig Woodson. He began teaching at Wesleyan in 1963, becoming that university's first Artist in Residence in Music.
Ranganathan's brother was the Carnatic flute player and vocalist T. Viswanathan (1927-2002). The two recorded the music for the Satyajit Ray documentary film Bala (1976), about their sister, the bharatanatyam dancer Balasaraswati.
Ranganathan died after a long illness, at the age of 62. He was survived by his wife Edwina, and sons Suddhama and Arun.