Singing in harmony is not easy, even for non-beginners, but with special practice it can be straightforward.
This video is one of three videos, of the same song, dedicated to this special practice, and this is how to use them.
Let's say, you'll be singing "Lakmé"; in this case, you need to listen repeatedly to the video below until you master your part:
Flower Duet [Lakmé] - BM
Once done, you start singing your part, but this time by using the video:
Flower Duet [Mallika] - BM
Once your part is mastered in harmony, you and your partner, who'll be sining "Mallika", can now sing this song together by using the video:
PIANO ACCOMPANIMENT of "Flower Duet - BM"
This method is very efficient for learning to sing in harmony.
If you have any questions and/or suggestions, I'll be glad to help. Good luck!
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From the opera "Lakmé".
Composer: Clément Philibert Léo Delibes (21 February 1836 - 16 January 1891).
Librettist: Philippe Emile François Gille (10 December 1831 - 19 March 1901) and Edmond Gondinet (born 7 March 1828).