Health

Performing artists must protect their bodies like athletes

Whether amateur or professional, performing artists have unique health needs specific to their art form. Musicians, singers, dancers, actors and other performers should always consider their own physical limitations and the ...

Health

Preventing hearing damage during summer activities

For many, summer means the sweet sounds of live concerts, fireworks, lawnmowers and splashing water. To optimize the fun summer sounds, here are some preventative measures to protect your hearing during these outdoor activities.

Other

Quiet please in the intensive care unit

A study presented at Euroanaesthesia 2016 shows that noise levels in the Intensive Care Unit (ICU) can go well above recommended levels, disturbing both patients and the medical teams that care for them. The study is by Dr ...

Health

Sounds of summer may threaten your hearing

(HealthDay)—Some of the most common sounds of summer—such as outdoor concerts, fireworks and construction—can pose a threat to your hearing if you don't take steps to protect yourself, an expert warns.

Medical research

In gerbils, stem cells boost hopes of ending deafness

Scientists working with deaf gerbils said on Wednesday they had found a way of coaxing early stem cells into specialised ear cells that helped the rodents hear sound once more.

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Decibel

The decibel (dB) is a logarithmic unit that indicates the ratio of a physical quantity (usually power or intensity) relative to a specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power quantities. A decibel is one tenth of a bel, a seldom-used unit.

The decibel is used for a wide variety of measurements in science and engineering, most prominently in acoustics, electronics, and control theory. In electronics, the gains of amplifiers, attenuation of signals, and signal-to-noise ratios are often expressed in decibels. The decibel confers a number of advantages, such as the ability to conveniently represent very large or small numbers, and the ability to carry out multiplication of ratios by simple addition and subtraction.

The decibel symbol is often qualified with a suffix, that indicates which reference quantity or frequency weighting function has been used. For example, dBm indicates a reference level of one milliwatt, while dBu is referenced to 0.775 volts RMS.

The definitions of the decibel and bel use base 10 logarithms. The neper, an alternative logarithmic ratio unit sometimes used, uses the natural logarithm (base e).

A change in power ratio by a factor of 10 is a 10 dB change. A change in power ratio by a factor of two is approximately a 3 dB change.

This text uses material from Wikipedia, licensed under CC BY-SA