[citation needed] His earlier 1940s gramophone recordings of Tagore songs, though still regarded as soulful and expressive, demonstrated stricter adherence to traditional musical rules, which he would subvert later in his career during the early 1960s.

[citation needed] His vocal range and variety of tempo and rhythm created renditions that were integral to the Bengali musical culture of the time.

[citation needed] Biswas caught the attention of authorities from 1964 onward due to the liberties he took by challenging the accepted tune-notations, scansion, tempo, beat, and rhythms commonly associated with Tagore lyrics.

He challenged the sensibilities of Tagore song listeners with the use of the Spanish guitar, the saxophone, the clarinet, the piano, and the cello, along with the sitar, the sarod, the esraj, and the violin.

His frustrations during this period are detailed in his autobiography, Bratya Janer Ruddha Sangit (or, The Stifled Music of an Outcast), published in 1979, a year before his death on 18 August 1980.