On the decibel scale, 0 dB is the smallest audible sound. This scale is called the decibel scale or dB scale. Therefore, a logarithmic scale is used to express sound levels meaningfully in more flexible numbers rather than a linear one. To calculate decibels, use the following formula:, where L is loudness and is 10 -12 which is barely audible. What is the Decibel Scale The human ear has the ability to handle an immense range of different sound levels. Likewise, if the ratios are 0.1, 0.01, and 0.001, the respective decibels are -10, -20, and -30.

If you were standing one foot away from a loud machine, for instance, you would experience higher decibel levels than if you were ten feet away, even though the intensity of the sound produced remains unchanged. For ratios P1/P0 equalling 10, 100, and 1000, the respective decibels are 10, 20, and 30. The intensity of a sound reaching a person's ear depends not only on the intensity of the sound produced, but also on the persons distance from the source of the sound. This appendix provides an introduction to logarithms (real and complex) and decibels, a quantitative measure of sound intensity. Though reducing the decibel level produced by a sound source from 80 to 77 may not seem like a major change, it would actually represent a 50% reduction in audible sound. Rather, each three decibel increment affects a 50% change in sound pressure levels. However, it is still important to understand when working with measurement scales that are logarithmic in nature, such as the bel (decibel) and Richter scales. If you wish to pursue a career in fields such as computer and data science, research, finance and business analysis, log scales are essential for you. A sound with a 50 dB level is not twice as intense as a sound with a 25 dB level. With the advent of high-speed, handheld, digital calculator devices, this elegant calculation technique virtually disappeared from popular use. A logarithmic or log scale is a method for showing substantial data or numbers compactly on a graph.

However, the relationship among the values on the decibel scale is not linear but logarithmic.

The intensity of sound is measured in a unit called the decibel (dB), which describes the relative intensity of a sound based on a logarithmic scale containing values ranging from 0 to 194.Ī zero value on the decibel scale represents the weakest sound audible to humans and sound intensity increases in correspondence with numeric values.

Logarithmic scale decibels