View Full Version : Low Frequency Sound

07-29-2008, 12:40 PM
Infrasound is sound with a frequency too low to be heard by the human ear (lower than 20Hz). So what's the point of a sound that we can't hear?
A steady 17 Hz sound wave is not within the range of conscious hearing, yet it does affect people.

Infrasound (between 17 and 19 Hz) has been proven to cause feelings of awe and fear in people.

In a 2003 experiment in the UK, 700 people were exposed to such a wave while listening to different pieces of music. (The musical selections were varied to avoid association of feelings with any particular musical piece.) The selections were played both with and without the 17 Hz undertone. Respondents reported anxiety, uneasiness, extreme sorrow, nervous feelings of revulsion or fear, chills down the spine and feelings of pressure on the chest only when the 17 Hz wave accompanied the music.

So...why not use infrasound to enhance the haunt experience? The effects dissipate as soon as exposure to the infrasound stops...it has no lasting physical effects. Plus low frequency waves are capable of moving around obstacles and last longer than higher frequency waves. (One wouldn't have to worry about room acoustics.)


07-29-2008, 02:10 PM

07-29-2008, 03:43 PM
And with Audacity, we can make our own infrasound tones. Stick a long PVC pipe onto a speaker, playback the sound, and well, there ya go. We've created a gist of what was used in the experiment.

Using infrasound in the haunt is an interesting concept, but not a new one.

07-29-2008, 04:30 PM
So...does anyone here currently use infrasound in their haunts? If so, are the results noticeable?

I'm trying to judge the R.O.I. of incorporating infrasound into a haunt.

RJ Productions
07-30-2008, 12:16 AM
One quick comment....actors.

Remember exposing the audience to the infrasound is one thing, quite a differnent effect if you expose your actors to it night after night!!!

07-30-2008, 01:03 AM
One quick comment....actors.

Remember exposing the audience to the infrasound is one thing, quite a differnent effect if you expose your actors to it night after night!!!

C'mon, horror is our pastime, our work place. No amount infrasound can make us uneasy in the haunt. :)

07-30-2008, 05:55 AM
I was thinking more along the lines of using infrasound along the que, but honestly hadn't thought of actor exposure.

07-30-2008, 08:37 AM
It'd probably be great as long as actors weren't exposed to it--no matter how hardened a scare performer you are the infrasound works on lower centers of the brain--the reaction is visceral.

Additionally, the lower frequencies travel well. If you're in a populated area--or near something that will help the noise travel you could terrify a whole lot of people who haven't paid for the privilege

08-25-2008, 11:34 PM
I just hope no one ever sues over such a device, claiming they can't sleep or perform sex afterwards. The lawyers will try anything these days, and they love to go after haunts with insurance. But we can't let such worries stop us from pushing the outside of that envelope, can we?

10-13-2008, 10:48 AM
Infrasound is amazing. It won't harm you, I have been acting in my "black out" scene at our haunt everynight for 4-5 hours at a time and it definitely does make you feel uneasy and nervous but goes away after about 10 minutes. What we do is put it in the first building so instantly they are feeling it. Buttkicker speakers definitely give that vibe you can't find with anything else.

10-13-2008, 10:59 AM
Also remember, some of this stuff is illegal... depending on what you do. Years ago TV commercials were using this tech. in their ads to get people to buy more of their product!!! The govt. cracked down on this and made some of it illegal. So, just be carefull!-Tyler

PS: Maybe you can play a clip... "buy more tickets"... in the pipe! hahaha... ;)

10-13-2008, 12:06 PM
Tyler, if you are being serious you are very wrong. Infrasound is not illegal, subliminal advertising with images might be.

Subliminal audio messages have never been tested to work by any real testing facilities and are crap.

I’ve studied infrasound for several years now and all testing has shown it to be harmless unless it is too loud which then it can damage your hearing just like normal audible sound. It has been tested in several different types of tests to have strange effects on people.

Creating infrasound cheaply is not easily done, if you think you can hook up your computer or your home stereo and blast out infrasound in is not going to happen. You might get a few db of infrasound but it will not do much.

If you guys are blasting low freq audible bass 20 to 60 Hz it may have some of the same physical effects on people as infrasound but unless you’re an idiot you know why….because you can hear the bass….

Infrasound is sub 20 Hz and unless you’re a dog most people can’t hear it. The infrasound generator that I sell produces some second and third harmonics that can be heard but again that is not the “Infrasound”

If you guys are trying to make your own infrasound generators and you do succeed in producing high levels, please be careful not to exceed levels that will damage anyone’s hearing. Testing this is very tough since 99% of the audio testing equipment does not test freq’s that low.

Good luck and be safe!