Qataadah Radiyallahu 'Anhu narrates that Allah gave to every Nabi that He had sent a beautiful feature and beautiful voice. Your Nabi Sallallahu 'Alayhi Wasallam also had a beautiful feature and a beautiful voice. Rasulullah Sallallhu 'Alayhi Wasallam did not recite in a melodious tone as singers do.
English reference: Book 43, Hadith 303
Arabic reference: Book 44, Hadith 320