Actually you can not "measure" the subjective feeling loudness in decibels with a "dB"-meter. You can objectively measure the sound pressure with a "sound pressure meter" that shows the sound pressure in pascals or the sound pressure level SPL in dB or dBA. SPL is a measure of the sound pressure present; dB above the Threshold of Hearing.
According to wikipedia, Loudness is the quality of a sound That is primarily a psychological correlate of physical strength (amplitude). More formally, it is defined as "that attribute of auditory sensation in terms of the which sounds can be ordered on a scale extending from quiet to loud.
Loudness, a subjective measure, is Often confused with objective measures of sound strength Such as sound pressure, sound pressure level (in decibels), sound intensity or sound power. Filters Such as A-weighting Attempt to adjust sound measurements to correspond to loudness as perceived by the typical human. However, loudness perception is a much more complex process than the A-weighting. perception of loudness varies from person to person it can not be Universally Measured using any single metric
Loudness is also affected by parameters other than sound pressure, including frequency, bandwidth and duration.
And the following illustrations to a loudness:
Reference: wikipedia.org |
Reference: wikipedia.org |
Alternatively, we can also measure the loudness level of audio with VU meters are available in hardware and software. You can find it in Loudness Measure category.