Hmm, that's quite interesting. I wonder about my characters' voices, but I haven't thought on how to explain them. I don't know why I used the Tenor-Bass and Soprano-Contralto types, even if it's specifically used for the opera.
So I got a handful of characters, my main Telluris acts like a confused grumpy old man, he'd mutter sometimes. I guess he's a bass-baritone, his accent is somewhere between Frisian or the southern accents of the Netherlands, maybe Groningen.
Then I've got a confident but calm Jorhaal, has a mix of a Finnish and Danish accent, dramatic mezzo-soprano range. She's adventurous and agile, but she's mostly a mother figure.
Leknu would sound and talk like an optimistic Lewa (a Bionicle character) Yes, the chutespeak/treespeak is present, is a falsetto/countertenor, and he'd probably have a mix of French and German accents. He acts like he's in his mid-thirties, he be the quiet and curious type.
Another one by the name Ferro has a more arrogant and sarcastic attitude, mix of Chinese and Turkish accents, lyric contralto voice range, acts around the young twenties age.
Ant that's about it regarding my characters, they're not often inside RPs, most of my writing happens in my own little world.