Harmonic Overtones, Magical Vibrations in Voice and Musicby Dick de Ruiter, is a great introduction to harmonic sounds and how to make overtones.
The package consists of a hardback book, packaged with two CD-ROM disks. The book is small, about the size of a CD jewel case, with 56 pages. It is beautifully designed and includes a good discography and resources such as Web addresses.
The photos are lovely (and relevant), and the concise, well-written text covers all the basics you need to know to begin overtoning. It starts with metaphysical and scientific effects of sound and moves on quickly to what overtones are, why we would want to make them, and how to get started.
As explained in my last post, you have almost certainly heard overtones, but you may not have recognized them. No amount of words can prepare you for the actual sounds, so the book includes a CD of music with overtones, including both voice and instrumental overtones.
This is probably the best recording of overtones I have, and I have at least a couple dozen recordings of Tibetan lamas, Tuvan musicians, Mongolian herdsmen, Americans who have learned overtone chanting, Bulgarian singers, and others. Some are museum-quality recordings. This is even better.
The only criticism I have of the example CD is that it mixes instruments with voice sometimes, making it just a bit less obvious that those magical sounds can be made by just one human voice. However the superb sound quality and clarity of overtones on the recordings make up for that.
The practice CD is unique as far as I know. The book tells you how to make the sounds, and then you can sing along for practice.
As Dick de Ruiter tells us in the book, making overtones is simple---but not easy. That is, the instructions are not complicated, but you do have to practice a lot, especially if you ever hope to sound as good as Dick and his fellow musicians on the CDs. They are really terrific!
The recommended price of this priceless book-and-CDs package is $23.50, but I ordered it from Amazon for much less. It is well worth the full retail price!
Dick de Ruiter has published other books and CDs on sacred sound, such as on Tibetan bowls, and he and his colleagues do a wonderful job on this and the other recording I have from them on Tibetan bowls. They also have a package on didgeridu. Theirs is truly soulful music.
The Harmonic Overtones book-and-CDs set is published by Binkey Kok Publications, Hofstede De Weide Hoek, Havelte, Holland. Watch for their other publications as well. They publish wonderful books and recordings on sounds for healing.