Change HZ

Ubuntu 20.04 Audacity 3.0.5


Hi there folks,

I have a spoken text which I want to adjust it’s frequency above and below the human hearing range…,
The so called subliminal and supraliminal.
My question is how can do that?

The most popular method for creating “subliminal messaging” is with “amplitude modulation”. This is similar to AM radio, except that it is done with high frequency sound waves rather than radio waves, and is at a much lower frequency than radio.
There is a “Nyquist plug-in” available here for this: https://forum.audacityteam.org/t/silent-subliminals-solved/20100/3
Installation instructions here: https://manual.audacityteam.org/man/installing_effect_generator_and_analyzer_plug_ins_on_linux.html#nyquist_install

Note that MP3 encoding is likely to strip out high frequencies as MP3 is designed to remove information that is inaudible (so as to reduce the file size while preserving the audible information).

“supraliminal” means “existing above the threshold of consciousness” / “adequate to evoke a response or induce a sensation”.
A normal audio recording played at normal listening volume is “supraliminal” because you can hear it.

“subliminal” means “inadequate to produce a sensation or a perception” / “existing or functioning below the threshold of consciousness”. In other words, you can’t hear it.

Thanks for your reply Steve!

Note that MP3 encoding is likely to strip out high frequencies as MP3 is designed to remove information that is inaudible (so as to reduce the file size while preserving the audible information).

I use VLC Player to play the audio files, so I might be able to use a different format than MP3. Do you know which file extension I can use for higher frequencies?

Do you know if I can adjust the frequency to 15,5Hz with the Nyquist plug-in?

Btw how can I edit my posts? I checked around but could not find a edit button…,

In the first post of the topic (Silent Subliminals [solved?]) the original author of the code recommends a carrier frequency of 15592Hz.

WAV is a good choice.


If you need to amend or correct anything from a previous post, make those comments in a new post (it can get very confusing if earlier posts are changed)

I should probably make a new thread for this but any way

i noticed today that the icons of the folders are no longer visible and that makes it somewhat difficult to differentiate between folders and file formats such as MP3.

Here is a screenshot what I mean.
https://imgur.com/a/52o8ouS
Normally it look like this (different program though)
https://imgur.com/a/V71K0bs
Screenshot from 2021-10-22 02-03-04.png
Screenshot from 2021-10-22 01-57-03.png

That would have been preferred.
How does your usual file browser (“Nautilus”?) display folders?

Topic split to: Folders Icons missing. - GNU/Linux - Audacity Forum