Definitions for

**"Decibels"****Related Terms:**Decibel , Bel, Dba, Vu meter, Sound level meter, Sound pressure level, Spl, Sensitivity, Sound power level, Amplitude, Spl meter, Noise figure, S/n, Volume, Differential mode noise, Neper, Loudspeaker, Dbm, Signal to noise ratio, Phon, Signal-to-noise ratio, Total harmonic distortion, Pink noise, Hum, Thd, Gain, Ambient noise level, Cmrr, Noise level, Level, Random noise, Harmonic distortion, Common mode rejection ratio, Sone, S/n ratio, Noise, Background noise, Loudness, White noise, Dbv, Speaker, Common-mode rejection ratio, A-weighted sound level, Peak-to-peak, Carrier-to-noise ratio, Electrical noise, Dbu, Microphone, Attenuate, Sound level

A unit of measurement that relates to sound.

A unit of measurement that indicates the loudness or intensity of sound, also used to measure hearing loss.

measurement unit of noise levels in housing. Examples : 40 dB quiet space, 80dB high traffic street, 130 dB pain threshold.

one-tenth of a bel, which makes this measure easier to use in normal conversation. Calculated bels are large numbers. A decibel is simply equal to 0.1 bels.

Decibels is a measure of sound pressure expressed on a logarithmic scale relative to the lowest sound the human ear can detect (P0 = 2 x 10-5 Pa) and is given as dB = 20 log10(P/P0) where P is the pressure in Pascals. The response of the ear to sound levels is logarithmic with a change of 1dB being the same perceived change at any level. A 1dB change is only perceivable under controlled conditions.

measure's a sounds loudness and refers to a ratio of a louder sound to a quieter one.

Measures the intensity or loudness of a sound. Zero dB is the quietest sound measured and 120 dB is the loudest sound commonly measured.

(dB) the measurement in the differences in power among sounds. The difference in decibels between two sounds is defined as ten times the common logarithm of their power ratios. a unit of the difference between two sounds in terms of the ratio between sound pressures. Each 10:1 sound pressure ratio is equal to 20 dB, so that a 100:1 ratio is equal to 40 dB. (H:551)

Decibels (dB) are used to express relative values of signals on a logarithmic scale.

A measure of the sound level (loudness). The decibel scale is a logarithmic scale; as an example, a 90 dB noise is ten times louder than a 80 dB noise. E - F

A unit of measurement of optical power which indicates relative power. A -10 dB means a reduction in power by 10 times, -20 dB means another 10 times or 100 times overall, -30 means another 10 times or 1000 times overall and so on.

A ratio of the power of sound signals; a power ratio of 2:1 is equivalent to 3 decibels (3dB). The decibel can also be used to measure 'sound pressure level': the loudness of sounds.

A unit for measuring relative power ratios in terms of gain or loss. Units are expressed in terms of the logarithm to base 10 of a ratio and typically are expressed in watts.

A logarithmic representation of amplitude ratio, defined as 10 times the base ten logarithm of the ratio of the measured power to a reference. dBV readings, for example, are referenced to 1 volt rms. dB amplitude scales are required to display the full dynamic range of a DSA. dB values for power or voltage measurements yields the same result.

Units for measuring sound.

a measure of the energy returned to the radar by precipitation particles after they are hit with electromagnetic radiation.

The logarithmic ratio between two signal levels. In video and audio, it is normally defined as: dB=20 log10(V2/V1)

Units for describing amplitude of sound frequencies to which the human ear is sensitive.

is a logarithmic ratio used to compare characteristics of electrical signals.

The logarithmic units used to describe sound intensity (or amplitude).

The measure of sound.

The unit used for measuring antenna gain. Decibels are abbreviated as dB, and you may also see dBm ( decibels relative to a reference level of 1 milliwatt) and dBi ( decibels relative to an isotropic radiator, or a single point antenna).

See basic antenna concepts.