What produce sound for the user without disturbing others
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Our wireless TV audio headphones let you hear all the details of your favorite TV show, without bothering others.
Wireless stereo headphones let you hear every detail in your TV show.
Soft-touch padded headphones let you listen in comfort for hours.
Infrasound, sometimes referred to as low-frequency sound, describes sound waves with a frequency below the lower limit of audibility (generally 20 Hz). Hearing becomes gradually less sensitive as frequency decreases, so for humans to perceive infrasound, the sound pressure must be sufficiently high. The ear is the primary organ for sensing low sound, but at higher intensities it is possible to feel infrasound vibrations in various parts of the body.
Infrasound arrays at infrasound monitoring station in Qaanaaq, Greenland
The study of such sound waves is sometimes referred to as infrasonics, covering sounds beneath 20 Hz down to 0.1 Hz. and rarely to 0.001 Hz. People use this frequency range for monitoring earthquakes and volcanoes, charting rock and petroleum formations below the earth, and also in ballistocardiography and seismocardiography to study the mechanics of the heart.
Infrasound is characterized by an ability to get around obstacles with little dissipation. In music, acoustic waveguide methods, such as a large pipe organ or, for reproduction, exotic loudspeaker designs such as transmission line, rotary woofer, or traditional subwoofer designs can produce low-frequency sounds, including near-infrasound. Subwoofers designed to produce infrasound are capable of sound reproduction an octave or more below that of most commercially available subwoofers, and are often about 10 times the size.