I know that some speakers can't reproduce the frequencies etc etc etc...but lets see.
The mosquito ringtone (http://www.moconews.net/the-mosquito-ringtone.html) is a 17khz sound that apparently teenagers and kids can hear, but adults can't. Can you?
Attached wav file.
edit: Another version, much more powerful, here (thanks felldownthewell)
edit2: A page with tones from 14khz-20khz here (thanks plinden)
The mosquito ringtone (http://www.moconews.net/the-mosquito-ringtone.html) is a 17khz sound that apparently teenagers and kids can hear, but adults can't. Can you?
Attached wav file.
edit: Another version, much more powerful, here (thanks felldownthewell)
edit2: A page with tones from 14khz-20khz here (thanks plinden)