24/7 Pet Web Search

Search results

1. Results From The WOW.Com Content Network

2. Decibel - Wikipedia

   en.wikipedia.org/wiki/Decibel

   The decibel (symbol: dB) is a relative unit of measurement equal to one tenth of a bel ( B ). It expresses the ratio of two values of a power or root-power quantity on a logarithmic scale. Two signals whose levels differ by one decibel have a power ratio of 10 1/10 (approximately 1.26) or root-power ratio of 10 1/20 (approximately 1.12 ).

3. Noise figure - Wikipedia

   en.wikipedia.org/wiki/Noise_figure

   The noise figure is the difference in decibel (dB) between the noise output of the actual receiver to the noise output of an "ideal" receiver with the same overall gain and bandwidth when the receivers are connected to matched sources at the standard noise temperature T0 (usually 290 K).

4. Sound power - Wikipedia

   en.wikipedia.org/wiki/Sound_power

   TL. v. t. e. Sound power or acoustic power is the rate at which sound energy is emitted, reflected, transmitted or received, per unit time. [1] It is defined [2] as "through a surface, the product of the sound pressure, and the component of the particle velocity, at a point on the surface in the direction normal to the surface, integrated over ...

5. A-weighting - Wikipedia

   en.wikipedia.org/wiki/A-weighting

   A graph of the A-, B-, C- and D-weightings across the frequency range 10 Hz – 20 kHz Video illustrating A-weighting by analyzing a sine sweep (contains audio). A-weighting is a form of frequency weighting and the most commonly used of a family of curves defined in the International standard IEC 61672:2003 and various national standards relating to the measurement of sound pressure level.

6. Noise temperature - Wikipedia

   en.wikipedia.org/wiki/Noise_temperature

   The noise factor (a linear term) is more often expressed as the noise figure (in decibels) using the conversion: = ⁡ The noise figure can also be seen as the decrease in signal-to-noise ratio (SNR) caused by passing a signal through a system if the original signal had a noise temperature of 290 K. This is a common way of expressing the noise ...

7. Sound reduction index - Wikipedia

   en.wikipedia.org/wiki/Sound_Reduction_Index

   The Sound Reduction Index is expressed in decibels (dB). It is the weighted sound reduction index for a partition or single component only. This is a laboratory-only measurement, which uses knowledge of the relative sizes of the rooms in the test suite, and the reverberation time in the receiving room, and the known level of noise which can pass between the rooms in the suite by other routes ...