AYAYAAA-WAAWAWAA-AYAYAAA-WAAWAWAWAA

[Il Buono]

I was wondering how Morricone did the main theme of GBU.  I suppose it's done by voice...?  Are they muted, transformed voices or it some screaming talent that did it?

That's what I love about Morricone.  You know it's Morricone but it never sounds the same as before (on contrary to most contemporary composers).  

[Ramon]

I'm not sure who made the sound, but its apparently it was inspired by the sound a hyena makes.

[Groggy]

  The first part was vocal, but from what I read the "Wawawa" part was performed by "speaking" into a harmonica.

[Il Buono]

 
Gee, the stuff they do those composers...

[shorty larsen]

Yes, it's a singer from the "Cantori moderni Alessandroni" who made the AYAYAAA-WAAWAWAA-AYAYAAA-WAAWAWAWAA theme.

Morricone himself tells that he was inspired by the sound of a hyena or a wolf.

[Jupa]

Yes,I've also heard Morricone was inspired by a hyeena's sound.However,people who don't know this will probably not recognise the sound for that of a hyeena.

BTW,I'm compiling a list of the occurrences of the "ayayee-wahwah" sound in television series and advertisements.See my topic "The ubiquitous GBU sound".