Dynamic range - Definition and Overview

Dynamic range is a term used frequently in numerous fields to describe the ratio between the smallest and largest possible values of a changeable quantity.

Examples of usage

Audio engineers often use dynamic range to describe the ratio of the loudest possible relatively-undistorted sound to silence or the noise level, say of a microphone or loudspeaker.

Electronics engineers apply the term to:

• the ratio of a specified maximum level of a parameter, such as power, current, voltage or frequency, to the minimum detectable value of that parameter. (See Audio system measurements.)
• In a transmission system, the ratio of the overload level (the maximum signal power that the system can tolerate without distortion of the signal) to the noise level of the system.
• In digital systems or devices, the ratio of maximum and minimum signal levels required to maintain a specified bit error ratio.

In music, dynamic range is the difference between the quietest and loudest volume of an instrument, part or piece of music.

Photographers use dynamic range as a synonym for the luminosity range of a scene being photographed; the light sensitivity range of photographic film, paper and digital camera sensors; the opacity range of developed film images; the reflectance range of images on photographic papers.