Learning control over formants and sounds energy distributions

Question

Using spectograms like Praat and Chrome Musiclabs Spectogram. I discovered that I can control my first formant by moving my tongue between front to back by consciously moving between the vowel [u] [ae] [a] [i] sounds. I further discovered that I could move between slightly different "l" sounds by pronouncing "l" while forcing a different vowel sound.

This seems to just be an exercise on just the placement of the body of the tongue, so it leaves the middle and tip of the tongue relatively free to move, and naively, I would assume that I could also practice those movements to produce a variety of other sound effects that would be visible in a spectrogram.

Are there reference materials on how various tongue movements will effect spectrogram readings?

Answer 1

I suggest the summary in this Q&A as a starting point. One thing to pay attention to is that formants are also influenced by what you do with your lips, larynx (if you lower vs. raise it) and somewhat by constriction of the pharynx. This means that in experimenting with different tongue positions, you need to monitor the rest of your articulatory apparatus,to make sure you're not accidentally protruding your lips.

Computation of formant values is not strictly a thing about linguistics and language, it is about physics and anatomy -- you are not limited to common vowel sounds. It may be instructive to engage in mildly bizarre articulations using the tongue (placing the under-side of your tongue on your soft palate) to see ow that affects formants, and then try to make sense of that given Johnson's explanations.