A harmony chorus apparatus collects an original of a vocal sound performed after a main melody pattern of a song, and adds a chorus sound derived after a chorus melody pattern of the same song to the vocal sound. A memory stores a main melody data representative of the main melody pattern and a chorus melody data representative of the chorus melody pattern which is designed in harmony with the main melody pattern. A pitch difference calculator sequentially retrieves the main melody data and the chorus memory data from the memory in synchronization with progression of the song, and calculates a pitch difference between the main melody pattern and the chorus memory pattern according to the retrieved main melody data and chorus melody data. A chorus generator shifts a pitch of the collected vocal sound by the calculated pitch difference to generate the chorus sound in the form of a variation of the vocal sound. A mixing device mixes the generated variation of the vocal sound and the collected original of the vocal sound with each other to thereby create a harmony of the song.
展开▼