Because of the distance that low-frequency sound waves can travel under water, a set of four ships emitting sound at 235 decibels could monitor 80% of the world's oceans for submarines.
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Such damage has long been suspected, since whales employ their own form of sonar for navigating and hunting, and also use sonar-like low frequency sound for communicating with each other (so-called whale song).
The high-frequency sound from the transmitter produces sharp reflections of small objects for the same reason that an electron microscope (which operates at high frequencies) can see smaller things than a light microscope (which operates at low frequencies).
The machine that Dr O'Brien and Dr Frazier have designed to get round these constraints consists of a transmitter that sends out a pulse of sound at a frequency of 6 kilohertz, and an array of 52 receivers that collect the reflections from anything buried beneath the surface.
The reason why this ends up being a secure system, says Amento, is because from person to person, the frequency of the sound remains constant.
The waterproof functionality doesn't come at the expense of the sound, either, with the Aquaris sporting high-definition sound with 48 channels with high frequency resolution and a 12 kHz frequency range.
As for the sound, Marshall claims that the Monitors have a frequency range that goes all the way down to 10Hz.
Furthermore, the LightSpeaker's 2.5-inch wide dispersion driver uses digital signal processing to optimize high- and low-frequency output for a full spectrum of sound.
Knols points out that this explanation also fails by its own logic because male mosquitoes only produce a sound of 700Hz, far lower than an ultrasound frequency.
It might sound fanciful, but I see it happen with enough frequency to validate it.
Anthem's true audiophile approach with ARC instead uses proprietary processing to compute each speaker's in-room frequency response and then computes a target frequency response for each to yield the optimal sound.
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The Hitachi Sound Bars feature four high efficiency full range speakers and two high frequency tweeters with state-of-the-art Class D digital amplifiers.
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