The duets with Asha – "Pehle Pehle Pyar Ki" and "Yeh Tujhe Kya Hua" both from Ilzaam in 1986 and "Tere Naina Mere Naina" from Aag Se Khelenge and "Chotasa Parivaar Hamara" from Dost in 1989 became known in their respective years. In the late 1980s, Kumar sang songs for Anil Kapoor in films including Tezaab, Yudh and Aag Se Khelenge and continued to sing for him in the 1990s. He was also the voice for newcomer Karan Shah in films such as Jawani, Anokha Rishta, Apne Apne and Chor Pe Mor and though the songs were popular, only Anokha Rishta and Chor Pe Mor were successful films.
He became the voice of Kumar Gaurav in the 1980s and their combination gave many hit songs from films such as Romance (1983), Teri Kasam, Lovers (1983), All-rounder and Telefilm-Janam. Among music directors, Amit Kumar was used more by Pancham from 1975 to 1994 and by Bappi Lahiri from 1983 to 1995. Kumar sang for almost all music directors and actors in the 1980s, and was the second-most preferred male playback singer in Hindi films, after his father Kishore Kumar. He had solo and duet songs in hit films such as Hum Paanch, Bulundi, Itni Si Baat, Hamari Bahu Alka, Anokha Bandhan, Ustaadi Ustad Se, Bheegi Palkein, Khatron Ke Khiladi, Maalamaal, Ilzaam, Anokha Rishta, Rama O Rama, Jaaydaad, Tridev, ChaalBaaz, Aag Se Khelenge, and Dost. In 1986, the song "Mary Tu Hoja Meri" from Anokha Rishta and the duet "Roz Roz Ankhon" from Jeeva were popular. In 1985, the duet "Dushman Na Kare" from Akhir Kyun was popular. He had several "chart-busters" in 19, and "hits" with the duets "Tu Rootha Toh Main Ro Doongi Sanam", "Gali Gali Dhoonda Tujhe" and solo songs "Halla Gulla Maza Hai" and "Mana Abhi Tu Kamsin" from the film Jawani (1984). The Asha–Kumar duet "Yun Toh Haseen Hazar" from Shradhanjali in 1981 became a hit.
Kumar's singing in "Aao Naye Sapne Bune", composed by Basudev for Main Qatil Hun (1984). In 1980, Kumar sang " Laila o Laila" for Qurbani.
Īfter the success of Love Story, Rajesh Khanna employed Kumar for playback singing in Fiffty Fiffty (1981) and then later in Aakhir Kyon? (1985), Ghar Ka Chirag, Jai Shiv Shankar, Swarg (1990) and Sautela Bhai (1996). Burman jokingly told Amit before its release that this song sounds like a bhajan. Then Amit sang all the songs for the 1981 film Love Story and won a Filmfare Award for the duet "Yaad Aa Rahi Hai" with Mangeshkar. Kumar's duet "Ka Janu Main Sajaniya" with Lata Mangeshkar and "Ram Kare Allah Kare" and "Humto Aap Ke Deewane Hai" with Rafi. The duets he sang with Lata Mangeshkar and Asha Bhosle began his public display. He sang in various films, including Aandhi, Aap Ke Deewane, Khatta Meetha, Gol Maal, Des Pardes, Ganga Ki Saugandh, Deewanagi (1976), Duniya Meri Jeb Mein, Parvarish, Humare Tumhare (1979) and Baton Baton Mein. He also did playback singing for Randhir Kapoor in Chor Ke Ghar Chor (1978) and Dhongee. In 1978, he sang "Aati Rahengi Baharein" in Kasme Vaade, for Randhir Kapoor's character. Kumar recorded 170 Hindi songs under R.D. This song was named the 26th most-popular film song of 1977 by the radio show Binaca Geetmala. Burman, by which he attained national fame. In the 1976 film Balika Badhu, he sang "Bade Achchhe Lagte Hain" by the composer R.D. His duets with his father, such as "Haseeno Ke Chakkar Mein" from Deewangee in 1976, "Nazar Lage Na Saathiyo" from Des Pardes in 1978 and "Sun Chache Bol" from Badthi Ka Naam Dadhi in 1974 became popular. The song was "Hosh Mein Hum Kahan", composed by Sapan Jagmohan for the film Darwaza, which was released in 1978.Officially his first released song was in Main Bhi Akela Hoon from the 1974 film Zindagi Aur Toofan. Kumar sang professionally for the first time, outside his father's composition, at the age of 21 in 1973. Singing career Early 1970s Īmit Kumar with his father Kishore Kumar during a live performance For the second film, Door Ka Raahi, a teenage Amit Kumar sang "Main Ik Panchi Matwaala Re", but it was removed from the final cut of the film. In the first, Door Gagan Ki Chhaon Mein he sang Aa Chalke Tujhe, Mein Leke Chaloon to his eleven-year-old son. Kishore Kumar had cast Amit as his son in two films that he produced. While his mother complained that he was singing "filmy" songs, his father decided to bring him to Bombay. At one such function arranged by legendary Bengali actor "Mahanayak" Uttam Kumar, the audience continued requesting encores. Like his father, Amit started singing from an early age and he used to sing at Durga Pooja festivals in Calcutta. Kumar is the son of singer and actor Kishore Kumar and Bengali singer and actress Ruma Guha Thakurta.