OSDev.org

Hello,
I have created a another strange program in Delphi, that generates a, preferably, sine-wave sound specified by frequencies of left and right channels.
I've created a 17550 Hz sound and played it with maximum volume on my headphones. Aaargh!... That was noisy and disgusting. I think i have very sensitive ears, though...

Do you, preferably adults, hear it?
http://inflaters-site.info/data/misc/zvuk.wav
Do not change the default frequency, please.

inflater

Argh the mosquitos have returned

btw, there's quite a bit of other noise in that file apart from that beep.

I saw formerly a program, that generated from PC speaker this high-pitched squeal to protect against mosquitos, but it not worked under WinXP. When I tried frequencies higher than 21000 Hz,.. they were barely hearable, but frequencies under 15000 Hz were disguisting sine tone.

I can send the whole source code of the program if you like.

inflater

i'm 18 and heard it. it gave my a ringing in my ear of the same frequency! aaaaaaaaaaahhhhhh, i cant get rid of it!, ok its gone

The ringtone which is an insanely high frequency...

Reminds me of the time when a student in class walked right up to the teacher with the phone ringing (the ringtone)... The teacher (>45) didn't hear a thing. A rather funny event...

What's funny is if they (students) don't take the ringtone off then get older and can't hear the phone.

My father, 53-year-old, heard it clearly

How strange. It sounds a lot lower pitched when played under winamp or media player. Put it through audacity, though and I can't hear it at all. Guess I'm getting old...

Audacity reports mean frequency at 17549 Hz. Using its sine wave generator, I've discovered I can only hear up to around 15000 Hz. Zooming in on the waveform, however, shows that its hardly uniform. Sampling errors and all. According to wikipedia, humans can hear up to ~ 22kHz.

Regards,
John.

You keep going up in frequency and it will start to propagate from the speaker wires into the house. You might also be able to buy a cheap pack of NPN transistors from Radio Shack and boost the power up to a couple milliamperes to get a couple of feet or something.

Attach some long wires to the microphone and if you are near a AM station tower you can hear broadcasts too. (I did this when experimenting and found out later a lot of people have done it before too)

Kevin McGuire wrote:You keep going up in frequency and it will start to propagate from the speaker wires into the house. You might also be able to buy a cheap pack of NPN transistors from Radio Shack and boost the power up to a couple milliamperes to get a couple of feet or something.

Attach some long wires to the microphone and if you are near a AM station tower you can hear broadcasts too. (I did this when experimenting and found out later a lot of people have done it before too)

I don't know why.. But this topic reminded me of a cool project I found once upon a time.

http://www.erikyyy.de/tempest/

jnc100 wrote:How strange. It sounds a lot lower pitched when played under winamp or media player. Put it through audacity, though and I can't hear it at all. Guess I'm getting old...

Audacity reports mean frequency at 17549 Hz. Using its sine wave generator, I've discovered I can only hear up to around 15000 Hz. Zooming in on the waveform, however, shows that its hardly uniform. Sampling errors and all. According to wikipedia, humans can hear up to ~ 22kHz.

Regards,
John.

I got up to 20kHz, then found that Audacity doesn't go any higher... I guess the reason is pretty obvious.

Edit: and I went down to 35 Hz.

Kevin McGuire wrote:You keep going up in frequency and it will start to propagate from the speaker wires into the house. You might also be able to buy a cheap pack of NPN transistors from Radio Shack and boost the power up to a couple milliamperes to get a couple of feet or something.

Attach some long wires to the microphone and if you are near a AM station tower you can hear broadcasts too. (I did this when experimenting and found out later a lot of people have done it before too)

Ask people with silver dental fillings and they'll tell you how to receive a radio station with them - sleep between two digital alarm clocks.

Brynet-Inc wrote:

Kevin McGuire wrote:You keep going up in frequency and it will start to propagate from the speaker wires into the house. You might also be able to buy a cheap pack of NPN transistors from Radio Shack and boost the power up to a couple milliamperes to get a couple of feet or something.

Attach some long wires to the microphone and if you are near a AM station tower you can hear broadcasts too. (I did this when experimenting and found out later a lot of people have done it before too)

I don't know why.. But this topic reminded me of a cool project I found once upon a time.

http://www.erikyyy.de/tempest/

That is really cool man , but I dont have *NIX and I have only a LCD monitor.... well, i have a CRT too, but it is dusty enough, I don't even know if it works...

inflater

Candy wrote: Ask people with silver dental fillings and they'll tell you how to receive a radio station with them - sleep between two digital alarm clocks.

That is wild.