While all the top leading ladies from the 1950s onwards preferred only one playback voice, Lata Mangeshkar, there is a long history of leading men and their association with specific singing voices, the most famous being Raj Kapoor-Mukesh, and Rajesh Khanna-Kishore Kumar.
Rishi Kapoor who started his career with Shailendra Singh abandoned his playback voice by the time he came to Sagar.
Salman Khan stood steadfast with SP Balasubramanian’s voice right from Maine Pyar Kiya where SPB sang Salman to superstardom with chartbusters like Aya mausam dosti ka and Mere sawaalon ka jawaab do. Salman's next collaboration with SPB was in Patthar Ke Phool where SPB sang a staggering 10 tracks for Khan. However these songs were not as popular as Maine Pyar Kiya or Hum… Aapke Hain Koun and Love. Although the latter was a flop, the SPB-Chithra rendered Saathia tu ne kya kiya is Salman’s signature tune to this day.
As for Hum… Aapke Hain Koun, SPB’s songs assuredly aggrandized Salman Khan’s stardom.
It was a very comfortable symbiotic collaboration. Salman responded to SPB’s vocal performance with the kind of empathy that we see when Rajesh Khanna would emote to Kishore Kumar’s voice.
The last full-fledged ghost voicing by SPB for Salman was in Raj Kumar Santoshi’s Andaz Apna Apna. SPB sang three songs for Salman. One of them Shola shola tu bhadke was not used in the film.
Why did Salman switch to other other voices like Kamaal Khan and Himesh Reshammiya in his later works? Did he have a fall-out with SPB? Nobody knows why SPB stopped being Salman’s ghost voice. But Salman is the only Khan superstar with a recognizable playback voice. Shah Rukh and Aamir use any voice that comes their way.
When RD Burman was recording songs for Ramesh Sippy’s Sagar, Shailendra Singh was designated to be Rishi Kapoor’s ghost voice and SPB was to sing for Kamal Haasan after their collaborative triumph in Ek Duuje Ke Liye. Kamal stuck to his ganas.