https://www.youtube.com/watch?v=w2_yXduElaE
As you can hear, the tone is very airy. It took me years to find it !
If anyone is interested in those "sub-techniques", please let me know and I'll show you how I do it
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My email is : [url=mailto:[email protected]][email protected][/url] and you can also find me on my page www.raphaelreiter.com