The tests measured range of hearing over low, mid and high noise frequencies.
So if you blast inaudible ultrasonic frequencies of 100 kilohertz and 101 kilohertz, you get an inaudible 201 kilohertz overtone plus an undertone of 1 kilohertz that is well inside the range of hearing.
HSS, by contrast, shoots tightly focused waves of ultrasound (meaning it exceeds the frequency range of human hearing).
The team expects that future, smaller designs will work at ultrasonic frequencies outside the range of human hearing.
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Second is the fact that FM signals have room for extra signals that are outside the range of human hearing but are good for transmitting data.
Usually, elephants produce much deeper sounds, sometimes of such a low frequency that they are outside the range of human hearing, and these calls can boom many miles away.
On average 45% of their hearing range was restored by the end of the study.
Sadly, much of this song is way beyond our typical hearing range, but with a little editing (read, slowing down) some of the squeaky-sonnets have been made audible.
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Twelve guides will aid people with both sight and hearing loss with a range of issues, including the use of computers, telephones and public transport.
When Dr Rydell and Dr Lancaster compared deaf and hearing moths from a wide range of habitats, they discovered how it is done.
Of course, we're hearing numbers that range from--well, up to 20, 000.
Now, Michael Merzenich, a neuroscientist at the University of California, San Francisco, and his colleagues have tested this idea by giving extensive hearing tests to grown-ups with a wide range of reading abilities.
So unless the magistrate conducting this week's extradition hearing surprises everyone by dismissing all the charges against the general, he faces a range of unattractive options.
"Sense, taste and smell and vision and hearing have a normal range, but there can be a hundred-fold between the ability of people to discern a taste or odour - it's not uncommon, " says Dietrich.
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