The dynamic range of a sound is the ratio of the strongest, or loudest part to the weakest, or softest, part; it is measured in dB (see WFTD archive “Decibel”). AN ORCHESTRA MAY HAVE A DYNAMIC RANGE OF 90 DB, MEANING THE SOFTEST PASSAGES ARE 90 DB LESS POWERFUL THAN THE LOUDEST ONES.
Dynamic range in audio equipment specifications is often confused with signal-to-noise ratio. Where signal-to-noise ratio is widely considered to be the available range between the normal operating level of a device and its noise floor, the dynamic range is the maximum range available, which would imply it is the range from the highest level attainable in a unit down to the noise floor. With analog systems dynamic range specs can be a moving target since it is known that in analog devices the onset of distortion is gradual. Defining a “maximum” level amidst onsetting distortion has not really been standardized in our industry, though most consider 1% to 3% distortion to be acceptable for this measurement. That means the dynamic range of an analog device can be thought of, unless otherwise specified, as the range between the noise floor and the maximum level attainable without going over 1% to 3% distortion.