Modified Frequency to Inaudible BUT STILL Audible?

Good day Friends,

Using version 2.0.5
Obtained the .exe installer
Also, I’m totally inexperienced with sound modifying!

Please help, I’ve read the manual’s explanation of changing Pitch and Frequency but my results is wrong.

  1. I would like to import a .WAV file of recorded voice audio and simply change the Frequency to the inaudible range of 19Khz then make a 2nd version at -40hz.

  2. So first, I selected the entire audio from start to end.

  3. Selected the Effects Dropdown menu and selected “Change Pitch”

  4. Then went to the Frequency “To” field and increased to the desired higher frequency of 19000 hz (19Khz).

  5. Then hit “Preview” to check, and although the audio sounds much higher like Alvin and the Chipmunks as expected, I could still clearly hear the sound which is all wrong because 19Khz should be essentially INAUDIBLE and silent from the speaker.

  6. PLEASE, what is the correct way to change up or down the frequency while maintaining the original speed, tempo?

Thank you for assistance in this matter

Digital Audio requires that the sampling frequency be at least two times the highest sound pitch. So for 40KHz “audio”, you would need a sampling frequency of at least 96000, not 44100, the Audacity default. If you’re trying to pitch normal audio up that far, you also have to worry about the sound range which could give you actual sound at 60KHz which in turn gives you a sampling frequency of 120,000. I think the nearest high one is 176,000.

Can your computer keep up with that?

Most sound equipment will not manage sound over 20,000Hz, some not even that high, so if you do manage to create a sound track that high, it will be an internal computer pet and not useful in the real world.

Are we searching for subliminal learning?


You can’t have a negative frequency.


Yes, that’s exactly what I’m trying to do, I have so much to memorize in my anatomy courses and I’m trying to grasp Spanish for the 2nd time now. So, I want to try and record the information and change the frequency to the inaudible range of like 19 to 21KHZ, so I’m trying to figure out how to do that? That way I could autoplay the track all night while I sleep, since it would be perfectly silent anyway, and who knows maybe the subliminal stuff actually works. But I cant seem to change the frequency properly?

  1. Then went to the Frequency “To” field and increased to the desired higher frequency of 19000 hz (19Khz).

What’s in the “From” field? You won’t necessarily get 19kHz unless you enter the TRUE “from” frequency… It’s not actually giving you a frequency, it’s just making a percentage calculation based on the to/from ratio.

What is your original WAV frequency? If it’s a regular voice or music file, it will have many frequencies and they will all be changed by the same percentage so your result will have many frequencies. If you have a regular voice/music file and you need to push everything above 19kHz, you’ll need to increase the frequency by a factor of almost 1000… But that’s simply NOT going to work, because only the lowest deep-bass frequencies will be at 19kHz and much of the audio will be pushed way-way up in frequency beyond the Nyquist limit (half the sample rate). i.e. 1000 times 10kHz is 10 MHz !!!

If you make an extreme drop in frequency, you are also going to loose information… Unless you reduce speed & pitch together. Then you can retain all of the information, but you will get a proportionally-larger file with a proportionally-longer playing time.

Sounds like thomp95 is trying one of those “subliminal message” things which Steve explained how to do here …