From: "Paul Roser" <pkroser@...>
Subject: Re: Conlang with whistles
> I've played around with the idea of whistles in conlangs
> for a while, and usually consider there to be three or
> four possibilities:
> 1) labial (though all of my whistles involve rounding)
> 2) retroflexed (probably equal to your alveolar)
> 3) front trilled (superimpose an alveolar trill on the whistle)
> 4) back trilled (superimpose a uvular trill on the whistle)
>
> if you added non-whistled forms as well, you could have
> /r, R/ for the front trill and /x, X/ for the back trill.
Don't forget having a voiced/voiceless contrast in whistles. And tone would
definitely be a feature.