[linux-audio-user] Create high-pitch noises like the mosquito device

[david]

Tim Howard wrote:
> On 3/30/07, listreader <listreader at lupulin.net> wrote:
>> I saw the mosquito device that will annoy younger
>> people, but not older people:
>>  http://www.compoundsecurity.co.uk/teenage_control_products.html
>>
>> Its pretty expensive.  How would I begin to create that
>> from scratch?  Can a sound-card generate those frequencies?
>>
>> I imagine I would need a special speaker.
>> How about an amp?, does that also need to transmit the
>> higher freqs.?  Is it like going from a bass amp to
>> a guitar amp? (and I need to keep going?)
> 
> It would likely be easiest to just make an electronic device like the
> one in the article...  Use a 555 timer (or other simple oscillator)
> hooked up to a small audio amp, then to a tweeter.
> 
> I know, I know, not a Linux solution...  ;-)

I bet somewhere there's a CSound or Supercollider patch that does it.

Also note that their claim about older people not being able to hear it 
(or younger people being able to hear it) is not necessarily true. It 
depends on the person. By the time I finished high school, I probably 
couldn't hear anything above 15KHz courtesy of loud hard rock music. I 
wouldn't be surprised if a number of the kids I see on the bus - the 
ones playing music through headphones so loud that you can hear the 
music six feet away - can't hear it, either.

-- 
David
gnome at hawaii.rr.com
authenticity, honesty, community