SoundproofingSoundproofing is any means of impeding sound propagation. There are several basic ways to reduce sound: increasing the distance between source and receiver, decoupling, using noise barriers to reflect or absorb the energy of the sound waves, using damping structures such as sound baffles for absorption, or using active antinoise sound generators. Acoustic quieting and noise control can be used to limit unwanted noise.
Johnson–Nyquist noiseJohnson–Nyquist noise (thermal noise, Johnson noise, or Nyquist noise) is the electronic noise generated by the thermal agitation of the charge carriers (usually the electrons) inside an electrical conductor at equilibrium, which happens regardless of any applied voltage. Thermal noise is present in all electrical circuits, and in sensitive electronic equipment (such as radio receivers) can drown out weak signals, and can be the limiting factor on sensitivity of electrical measuring instruments.
Weighting filterA weighting filter is used to emphasize or suppress some aspects of a phenomenon compared to others, for measurement or other purposes. In each field of audio measurement, special units are used to indicate a weighted measurement as opposed to a basic physical measurement of energy level. For sound, the unit is the phon (1 kHz equivalent level). Sound has three basic components, the wavelength, frequency, and speed. In sound measurement, we measure the loudness of the sound in decibels (dB).
Audio headsetHeadsets connect over a telephone or to a computer, allowing the user to speak and listen while keeping both hands free. They are commonly used in customer service and technical support centers, where employees can converse with customers while typing information into a computer. Also common among computer gamers are headsets, which will let them talk with each other and hear others, as well as use their keyboards and mice to play the game. Telephone headsets generally use loudspeakers with a narrower frequency range than those also used for entertainment.
Low-power wide-area networkThis needs to include cellular LPWAN technologies such as NB-IoT, LTE-M, Cat-M1 A low-power, wide-area network (LPWAN or LPWA network) is a type of wireless telecommunication wide area network designed to allow long-range communication at a low bit rate between things, such as sensors operated on a battery. The low power, low bit rate, and intended use distinguish this type of network from a wireless WAN that is designed to connect users or businesses, and carry more data, using more power.
EarplugAn earplug is a device that is inserted in the ear canal to protect the user's ears from loud noises, intrusion of water, foreign bodies, dust or excessive wind. Since they reduce the sound volume, earplugs are often used to help prevent hearing loss and tinnitus (ringing of the ears). The first recorded mention of the use of earplugs is in the Greek tale Odyssey, wherein Odysseus's crew is warned about the Sirens that sing from an island they will sail past.
