Star Wars and a return to the low-frequency side of the Force- part 2

In part 1 of this blog series, the use of 80 Hz was discussed as an important part of the force in Star Wars. Even Darth Vader knew that an 80 Hz rumble would enhance his control over the dark side but in 1977 (Episode IV) this would have been difficult.  If Darth Vader had survived episode VI and was back for this third generation of Star Wars sagas, I have it on good authority that he would have approved of this low frequency rumble – after all, he was Darth Vader!

One thing that Dark Vader would not approved of is a 10-18 Hz infrasonic rumble which makes people urinate. I am pretty sure that his black storm trooper type suit does not have sanitation facilities built in.  Actually it was a really stupid suit to begin with and I have written Darth letters in the past explaining why.  If one wants to hide one’s weaknesses, why are those stupid flashing status lights on his chest that give away information?!  I am pretty sure that they teach that in the first semester of evil villain school.

What would happen (actually does happen) in the infrasonic realm of hearing?  What about a 15 Hz rumble?  Would that enhance the strength of the Force on a movie screen?  The chart below from the B & K Technical Review (No. 1, 1982, p. 13) gives some influences on the human body from noises in certain frequency regions.

Feeling of discomfort 4-9 Hz

Head symptoms

13-20 Hz

Lower jaw symptoms

6-8 Hz
Influence on speech 13-20 Hz
Lump in throat 12-16 Hz
Chest pain 5-7 Hz
Urge to urinate 10-18 Hz
Influence on breathing 4-8 Hz

In the 1970s some (unscrupulous) movie theatre owners would generate a 10-18 Hz sound “encouraging” their clientele to get up and go to the washroom … and of course pass by the concession stand for a second round of Raisonettes and Coke.

In the 1974 movie Earthquake starring Lorne Greene and Charlton Heston, whenever the Los Angeles tremors began, a 6-8 Hz vibration was emitted by large subwoofer loudspeakers aimed into the floor of the theatre.  This gave the audience the “I-am-there” feeling as the skyscrapers collapsed.


From the Wikipdedia page

After several ideas were tossed about (which included bouncing styrofoam faux “debris” over audience members’ heads), Universal’s sound department came up with a process called “Sensurround” – a series of large speakers made by Cerwin-Vega powered by BGW amplifiers, that would pump in sub-audible “infra bass” sound waves at 120 dBA (equivalent to a jet airplane at takeoff), giving the viewer the sensation of an earthquake. The process was tested in several theatres around the United States prior to the film’s release, yielding various results. A famous example is Grauman’s Chinese Theatre in Hollywood, California, where the “Sensurround” cracked the plaster in the ceiling. The same theatre premiered Earthquake three months later – with a newly installed net over the audience to catch any falling debris – to tremendous success.”

For any of this to work properly, very large loudspeakers had to be installed that were able to provide the audience with a sufficiently upsetting tactile response. This technology was used in several movies throughout the 1970s and 1980s including BattleStar Galactica – another Lorne Greene movie.  (Did you know that Lorne Greene was Canadian, eh?).

Infrasound spectrum

Wouldn’t it be neat if hearing aids, or at least our Smart Phones, had infrasound emitters in them to help up enjoy the otherwise boring experience? Oh- wait a moment – they do!  It’s in the vibrate mode function.  Imagine music listened to through our Smartphones with the occasional very low-frequency infra-sound added to the music. Just a thought…

About Marshall Chasin

Marshall Chasin, AuD, is a clinical and research audiologist who has a special interest in the prevention of hearing loss for musicians, as well as the treatment of those who have hearing loss. I have other special interests such as clarinet and karate, but those may come out in the blog over time.