Azad passed away in a Dhaka hospital around 4:45 pm on Saturday, film producer Gazi Kibria Lipu told.
Citing his family, Lipu said the musician had undergone a surgery some days ago.
He suffered a heart attack before his death and had no symptoms of the coronavirus, Lipu said.
The body was kept at the hospital’s mortuary.
Called the father of Bangla Kheyal, Azad had taught at the Nazrul Institute.
He won the National Film Awards as a singer once and as a music director two times.
Among the famous songs composed by Azad are Jonmo Amar Dhonyo Holo Maa Go, Bhalobasar Mulyo Koto, O Chokhe Chokh Porechhe Jokhoni, Monero Ronge Rangabo and Dorakata Dekhe Bagh Chena Jai.
He debuted in film music through “Miss Priyambada” premiered in Kolkata in 1967. Azad and Subir Sen jointly worked for the film’s music and legendary actor Bhanu Bandopadhyay starred in it.