Mohd rafi was a prolific singr used by all composers except sapan chakravortyeven though some of them like salil choudhary, c. ramchandra did not like him . anil viswas particularly disliked him. his voice was the voice of Dilipkumar, shammikapur and almost all strs in fifties and sixties except for rajakaput(mainly used mukesh/manna dey) and dev anand(kishorekumar)
he really ruled in sxitis but after 1969 release aradhana he was eclispsed by kishorekumar and thjough he sang in seventies the real key num, bers especially serious soft numbers were sung by kishore3kumar. but he was appreciated for quawallis . unfortunately for classcial and semiclassical numbers Bhupendra, Yesudas wewre used. YEsudas particularly demonstrted the limitations of RAFI on this front.
but he was very versatile and could sing high pitch notes very easily though not particularly good at low pitch singing and lacked depth, tenderness and softness in the voice to desired extent occassionally. He had a great phirat in voice like asha bhonasale and it was said that mohd rafi was lata mangeshkar in males. There was nothing impossible for his and lata’s throat .kalyanji rates him as technically tyhe most perfect suinger and he was! Actually some of the qualities of lata a as well as asha were with Rafi( likle phirat of asha, the high pitch of lata, the meldy of lata)andsome of the qualities like depth and softness of lata and the thickbass of asha were with kishore. In many duets and tandems with the nightingale of india "lata" Rafi outshines LATA for example "jiya ho jiya kush bol do", "parbat ke us par", But in the tandem with kishore "tum bin jau kahan " kishore exceled and in many duets with asha Asha outshines for example "gun guna rahe hai", "abhi na jao chode ke", "chura liya hai tumne" etc. At one time he was so indispensible that when there was dispute over royalty with lata it was lata who was replaced by suman kalyanpur in duets like " dilke zaroko me " . but in late sixities his voice was cacohpnoous especially in shankar jaikishan’s compositions like "badan pe sitare", "shadi ke liye" and the song "duniya hase hasti rahe " was a example of falling grace of both rafi and naushad earlier being witnesed in "ram aur shyam". But he made a good and brave comeback in late sevnties with nicely sung quwwalis "parda hai" and "hai agar dushman". incidentally the tunes of both quwallis comosed by Lp and RD burmman respectively are remarkably similar. But his singing at the end of his carrear was much below his standard especially in tunes "maine pucha chand se and "darde dil " He was promoted extensivly by LAxmikant pyarelal especially in his lean phase but since they composed mostly run of the mill or at the best b grade tunes rather than helping his carrear it actually harmed the reputation of the singer. rafi sang maximum songs under LP and yet many rate this combo as boring and dull. Rafiss combo with SD burman, O.P nayyar and rd burman(occassionally) were superb. who can forget "khoya Khoya chand". he sang some good duets and tandems under shanker jaikishan and kalyanji-anandji.
his combo with naushad is loved by nerds in HFM. though he sang a lot with rosahan roshan is more rembered with songs by lata and Mukesh. He sang a lot with chitragupta as well.
Famous are his remarks after his come back " abhi ye Baat to achi sabit hui hai ki kishore be accha ga late hai. Ye saga dekhkar to muze be laga ki muze bhi aur kuch sinnging me karna hai. aisa lagata hai ki abhi muze kuch gine chune ganoke liyehi bulaya jayega- MAdhuri film magazine interview" " . It seems though LP favored rafi they and rdb were together in making kishore topmost in 1971 and it seems when the imbalance was rectified again LP and rd burman together decided to give a lft to RAFi as they wanted to avoid the monotony and excess. The overdose of Rafi in late sixities resulted in replace ement of rafi by kishore and anew generation of music composers LP, R.d burman, Kalyanji anandji emerged. They wanted to avoid the recurrence of this phenomenon and with a calculated move they brought Rafi back but to a certian extent and both LP and RD burman avoided Yesudas even after "Yesudas’s splendid performance in "chitchor"
After rafi’s death they promoted SPB for the same reason as they feared that else new music directors regime will follow, and to avoid this they used a well known singer from south but SPB’s Hindi diction was very poor. It should be noted that after kishore’s death both Lp and RD burman rarely used SPB even after success of SPB under the baton of Ramlaxman!
So Kishore and Rafi suited the popular Hindi film music best though more serious light musi like "Marathi music " would have necessitated use of other male singers! in addition!