I'm trying to understand some basics, hope this is an ok question.
Here's a recording of me producing /i/, /ɛ/, /a/: https://namakajiri.net/misc/i%c9%9ba.webm
nevermind the transition between the first 2 vowels.
I’m a Brazilian Portuguese speaker, but judging from articles I’ve just browsed, the typical formant values in my language aren’t much different than the ones for the closest English vowels.
Here’s the spectrogram:
I think it’s easy to see F2 and F3 shifting at more or less plausible values (~2370, 2000, 1550Hz; ~3000, 2800, and a bit diffusely, 2300). But for F1 I have a persistent dark band at ~260Hz that loses a bit of intensity for /ɛ/, /a/ but otherwise doesn't budge at all. Maybe plausible for /i/ but way too low for the other vowels?
There’s a bit of energy above it that becomes a clear formant for the latter two vowels, at ~660Hz, which would be a plausible F1 for /ɛ/. But it doesn’t seem to move for /a/, and the bottom 270Hz band stays there.
Is my interpretation of this correct? If so, what is this low 260Hz band below F1?