A method and apparatus to facilitate tone challenged singers to sing intended notes. In one aspect, the singer determines a note to sing corresponding to an intended frequency fi. The singer utters a note continuously with fundamental frequency fu into a microphone of the natural ear apparatus. The note is processed by the apparatus to produce sound emphasizing the fundamental frequency fu and output through a speaker to the auditory organs of the singer. The singer detects differences between intended frequency fi and uttered fundamental frequency fu. The singer adjusts his vocal organs as he utters the note with the intention of changing fu to reduce difference between fi and fu.