A Vocal Mystery

I've been listening quite a bit to Natural Snow Buildings and TwinSisterMoon this past year, and puzzling over whether or not the person who sings in TwinSisterMoon is Mehdi or Solange. Here's the thing: Natural Snow Buildings is comprised of Mehdi and Solange, while TwinSisterMoon is supposedly Mehdi's solo project. But the vocalist on TwinSisterMoon sounds female, and Mehdi is male. Yet there are a number of blog posts out there saying that is for sure Mehdi's voice, however girly it may sound, while at least one other blog states that it was actually Solange guesting on the vocal tracks.

Natural Snow Buildings clearly sounds like it has two vocalists, one that sounds 'male' (which I assumed was Mehdi) and one that sounds 'female' (which I assumed was Solange). Here is an example of the 'male' sounding voice:

And here is an example of the female sounding voice:

Now compare with the vocalist for TwinSisterMoon:

What the hell? Is that really Mehdi singing there? Is it possible that a biological male could sing that high, without the nasal sound of a falsetto? Heck I can't even sing that high, period. But I am willing to accept that it is him, if it is true, which I don't feel certain about.

Then check Solange's solo project "Isengrind." I've only heard two of the four albums she's released, but the vocals all pretty much sound like this:

...the vocals are so distant I can't tell if this is the 'male' voice from NSB or the 'female' voice. If anything, this sounds like a third person entirely! If Solange is capable of any of the beautiful intimate singing I hear on either NSB or TSM, then I can't imagine why she would want to make herself sound so monotone and processed on Isengrind.

I realize there are more important issues in the world I should probably be concerning myself with. Ultimately...I enjoy it when I can't tell if someone is male or female. But I would like to know the truth...it is frustrating to see music bloggers stating completely different 'facts' about who is singing what.

What would really help is a bit of live footage showing them singing, but I haven't been able to dig that up. If anyone can definitively answer the question of who is singing which of these songs, I'd love to see your comment!