Well, there's a tehnique used by Mariah Carey especially, when you're singing very high, make it sound special, a "head" voice. i don't know if this is the best name to say. for example, in her song named Emotions, when she says "Inside" (I don't know if it's real, but i'd like the way it feels inside) - or in All I want For Christmas is You - at the last chorus... (All i want for Christmas iiiis... you) anybody here knows how to make this/ how to place the sounds that are coming out?!
also, any sites/information/lessons about voice performance - is good and it will help me for sure

Sorry no tips.

Actually, Mariah Carey's high notes are made using a special part of the larnyx called the whistle register. What I usually do when I sing is I like to focus on the area the note comes from and imagine the sound coming from that part of larnyx, so for hitting those coloratura notes, I direct my path of air flow into the top and back of my head. I don't really know how to explain it, but I hope that helps some.

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Oh, and a common mistake people make when attempting notes above the staff is "reaching" for it. Instead, try directing the pressure down, like pulling a slinky downward, so as to get the best support from your diaphragm and properly allign your air flow, but imagine the sound coming out the top of your head, so as to get a clear, pure sound, and then just let the note float on top of your breath. If you need any more help, I can ask my voice teacher for tips on those high notes.

thanks a lot! so little things you find on the internet ...