Help needed! (how to create this certain audio effect?)

Okay so without getting into the topic of subliminal messages working or not, I want to know how to get this same audio effect/balance that this video linked here has: https://youtu.be/lHMmP_y6TJQ?si=SsFK2LjhFOvfDBxN

I’ve tried to recreate my own with mobile apps or even audacity but it always seems as if my affirmation audio file is too clear to decipher. Has there been some sort of eq placed on the affirmation audio in that YouTube video I linked that makes them less easy to detect? I was also thinking that maybe it could be that the noise they used is in the frequency ranges of human speech. But anyways any help is appreciated!

2 complimentary* comb filters have been applied to each channel


The constant parallel horizontal stripes on the spectrogram are the tracks of the combs.

A plugin like Ozone imager will do this … https://www.izotope.com/en/products/ozone-imager.html (free)

[ * if you mix down to mono, the comb effect disappears: the combs perfectly cancel each other out ]