How to record a whistle utau?

[iXari3l]

So I have been recently curious about creating a VB similar to those "joke" vbs that are made out of sounds of pets or just instrument samples.
I also got inspired by someone to make a whistle UTAU.

How do you oto these samples?

There's no vocal or consonant. If it's a CV, (wich I suppose it's what it could be) how is it supposed to be oto'ed?
I'm assuming that there needs to be a "vocal" equivalent and a "consonant-vocal" equivalent???
Errrh it's hard to explain so if it's neccesary I'll make a visual explanation of what I mean

 

[FelineWasteland]

Since it's a continuous tone with no articulation, I'd assume you'd oto it like a vowel. I'd think the best results would be to have an initial [- X], sustained [X], and ending [X -] sample that could be blended together.

 

[iXari3l]

Since it's a continuous tone with no articulation, I'd assume you'd oto it like a vowel. I'd think the best results would be to have an initial [- X], sustained [X], and ending [X -] sample that could be blended together.

Something like a CVC, maybe ?

But yeah I can understand what you're saying