4

Hello all, this is my first question on this forum.

I'm curious about the use of infrasound in films/movies. I believe a number of studies have shown that infrasound (frequencies below 20Hz) can be used to instill a sense of suspense or even fear in a subject. In particular 19Hz is the resonating frequency of the eyeball and it has even been reported that this frequency can create visual disturbances.

So, are these infrasound tricks common in sound design circles or frowned upon? Anyone have any funny stories or confessions? Perhaps infrasound can also be used to induce more positive feelings in an audience.

Just curious, Iais

| improve this question | |
  • 2
    When I was studying sound in '96 one of my instructors had a story about a time when a neighbor of his became a real jerk and would turn his music and tv up real high whenever my instructor would ask him to turn it down. After a while the instructor brought a frequency generator home from work and plugged a speaker into it & placed the speaker at the wall facing into the neighbors apartment. He generated a number of ultrasonic frequencies through the wall for hours at a time. Within a few weeks his neighbor started getting real sick and had to go to the hospital for some unknown reason. – Edwardo Santiago Jan 24 '11 at 4:13
  • Haha! We've all had that guy as a neighbour I guess. No long term damage I hope though. – IASM Jan 24 '11 at 5:34
  • Problem is that now I'm that guy with my 5.1 setup housed in a spare bedroom that adjoins to the neighbor's wall in a town home. Glad she sells school text books for a living and not frequency generators. – Edwardo Santiago Jan 25 '11 at 0:07
3

I think that would be awesome if it was possibly being put into practice. Some would call it a bit manipulative, or the opposite, to be interpreted by the audience - yet art in general is supposed to be like that is it not?

However, I know that infra and ultra sonic frequencies have to be produced by special transducers. I am not aware of theatre speakers that can output such an extended range of frequencies. I may be totally out of the loop though. (Maybe Lucas' water-tank subwoofers)

If directors and sound teams were implementing such sounds, they would have to guarantee the use of these tools at each theatre that screened their show. So its not ultimately up to the flick, but up to the theatre showing it. Seems a bit hard to believe.

Pretty cool idea though.

| improve this answer | |
1

Generally speaking, manipulation is something that we as sound designers regularly strive to do. Every time you use contrast to heighten the emotions of a scene, you are in effect manipulating the audience.

So using infrasonic frequencies to heighten the emotion of the scene sounds like a good idea. Whether or not it actually works in practice is an entirely different thing though.

| improve this answer | |
1

technically infrasound needs high intensity/volume to "work", no? i wouldn't class these as psychoacoustic tricks. if 8 hz stops your heart from beating normally, it, ahem, sounds quite physical to me..

| improve this answer | |
  • I did ponder whether the 'psychoacoustic' name was correct here. I'm not sure about volume intensity. I conducted some tests with a friend using some small speakers hooked up to a sound card and a software signal generator set to 19Hz. Even at low volumes the speaker cones were visibly moving and we definitely felt an 'uneasy' effect after about 10 minutes. I do recall, though, that what felt like 10 minutes actually turned out to be about half an hour! – IASM Jan 24 '11 at 18:49
0

Mythbusters has an episode where they search for the so-called brown note: a frequency that supposedly triggers loss of bowel control.

Starts after a minute or so. Their attempts are unfruitful even though they tested from 5 Hz up to 100 Hz.

[youtube]http://www.youtube.com/watch?v=GL2zK8cpkdY[/youtube] http://www.youtube.com/watch?v=GL2zK8cpkdY

[youtube]http://www.youtube.com/watch?v=piLoZ-eihXM[/youtube] http://www.youtube.com/watch?v=piLoZ-eihXM

Edit: the youtube tags seem broken?

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.