low frequency sound maker

[mowgli]

anyone on here into making electronic devices????

I am looking to buy or make a low frequency sound generator to do the following:

scare people..


I saw a thing on the tv a while ago where they reckoned that tigers emit low frequency sound (20-25Hz) and it strikes fear into their prey.. the same effect is blamed for hauntings & ghostly presences, which is what I want it for.. I want to make a unit that gives off a scary feeling on a museum display that I installed this morning. I placed a medieval stone coffin into a small open shelter at a local museum..

[L14MNP]

Locate the brown noise and that will scare more folk than you ever imagined.

[Welsh Dan]

http://www.electronic-circuits-diagrams.com/alarmsimages/5.gif

That'll do about 1khz, if you change the 10k resistor you change the frequency, a 5 megaohm resistor should bring it down to about 20Hz. The chip is a 555 timer which are pretty common.

[mowgli]

/\/\ ta very much.. I haven't set foot in an electronics shop for 23 years, but now is as good a time as any. It would be a good laugh if it works.

any ideas on an led to show it has power? I am thinking a pp3 for a power source

[mowgli]

Locate the brown noise and that will scare more folk than you ever imagined.

urban myth... I can easily get people to cack themselves at the museum, I have a key for the toilets......;)

[Welsh Dan]

Just connect the positive terminal of the battery to a resistor then to the LED then to ground. If you look at the inside of the LED, the big 'flag' bit is the negative side. The resistor value will depend on the maximum current the LED can handle. For example if its 15mA then you'd need a 600ohm resistor.

Using V(voltage) = I(current)*R(resistance) :thumb:.

9=0.015*600

[mowgli]

ta yet again. d'you think I will need a special speaker for that low frequency?

[L14MNP]

urban myth... I can easily get people to cack themselves at the museum, I have a key for the toilets......;)

and here's me fully believing it was real...

[Welsh Dan]

You're welcome.

Special, probably not. When you buy one from the likes of maplin they'll list the frequencies that the speakers can cover, just make sure 20hz is within that range or use a buzzer that covers that range.

[mowgli]

I hope it works, because there might be a market for it. it is actually planned as a deterrent, to stop kids from climbing into it & damaging it. the stone coffin is at least 800 years old

[Sloth]

hit 33Hz and ladies come........

[mowgli]

hit 33Hz and ladies come........

is that the frequency of Chocolate?????????

[draper]

is that the frequency of Chocolate?????????

or shopping

[Sloth]

i knew id get them replys...... sadly its not that type of come, or id be surrounded by em....

[draper]

i knew id get them replys...... sadly its not that type of come, or id be surrounded by em....

actually it is ;)

[Sloth]

psh, i spell it cum matey, tis yorkshire for ya hahaha!

[Southie]

urban myth... I can easily get people to cack themselves at the museum, I have a key for the toilets......;)

Was that the film with Ben Stiller "A sh1te at the museum" :D

[Welsh Dan]

The best deterrent for kids is actually a high frequency one (aswell?) its uncomfortable for them so they don't hang around near our spar since they got one fitted outside, but us oldies can't hear them.

[mowgli]

The best deterrent for kids is actually a high frequency one (aswell?) its uncomfortable for them so they don't hang around near our spar since they got one fitted outside, but us oldies can't hear them.

I know about the high pitch squeak one, but I can't see how it could work in merseyside;)

I want to try the subconscious put the bejaysus up someone but they can't work out why method.....

[mowgli]

Was that the film with Ben Stiller "A sh1te at the museum" :D

no that was a sh1te film at the museum

[Welsh Dan]

Nothing will stop that lot breaking in/stealing! lol

[meritlover]

Locate the brown noise and that will scare more folk than you ever imagined.

you're right! i made the brown note about 10 mins ago. people still havent come back

[mowgli]

Nothing will stop that lot breaking in/stealing! lol

I was actually making a comment based on their spoken accent... & the fact that if you played a high pitched squeak no-one would be surprised, they would just think someone else had joined the conversation

[ade]

you been watching Most Haunted or summut?!?

For a eal scare you want a corridor with 2 rooms either side and as someone walks but theyre hit by a blast of air - a simple trigger mechanism twangs a rubber cone shaped device that sends a channel of air down a tube hitting the person in the side of the hear. If its cold it feels like youve been touched by a ghost! Seriously feckin freaky!

Merge that with your device and theyd need load themselves!

I always wanted to build a threamin...just for the mad funky noise effect!

[Welsh Dan]

I was actually making a comment based on their spoken accent... & the fact that if you played a high pitched squeak no-one would be surprised, they would just think someone else had joined the conversation

lol thats true aswell :).

[Jack]

I always wanted to build a threamin...just for the mad funky noise effect!
Theremin?

See: Portishead lol

[mowgli]

and all of a sudden its become the all new scooby doo show

[16v Nova Kev]

i think thats a great idea mowgli:)

[mowgli]

you been watching Most Haunted or summut?!?

For a eal scare you want a corridor with 2 rooms either side and as someone walks but theyre hit by a blast of air - a simple trigger mechanism twangs a rubber cone shaped device that sends a channel of air down a tube hitting the person in the side of the hear. If its cold it feels like youve been touched by a ghost! Seriously feckin freaky!

Merge that with your device and theyd need load themselves!

I always wanted to build a threamin...just for the mad funky noise effect!

I just thought the cameraman had a ken dodd tickling stick.... & at the right moment, ran it past some has beens neck.....

[Sloth]

*cues benny hill music*

[DaveyLC]

I saw a thing on the tv a while ago where they reckoned that tigers emit low frequency sound (20-25Hz) and it strikes fear into their prey.. the same effect is blamed for hauntings & ghostly presences, which is what I want it for.. I want to make a unit that gives off a scary feeling on a museum display that I installed this morning. I placed a medieval stone coffin into a small open shelter at a local museum..

Deaf people are scared of tigers too!

[mowgli]

Deaf people are scared of tigers too!

you don't say!!