Decibel

, the threshold of human hearing. In digital audio, (Full Scale) measures signal level relative to the maximum a system can handle before clipping. Examples of Common Decibel Levels

: Adding a second identical sound source (e.g., two identical 60 dB vacuum cleaners) increases the total level by only 3 dB , resulting in 63 dB, not 120 dB. Decibel

: Many free apps are available on the Google Play Store or Apple App Store. While convenient for general checks, they may lack the calibration required for official evidence. , the threshold of human hearing

: Named after Alexander Graham Bell, a decibel is literally one-tenth of a "Bel". The Bel itself was found to be too large for common precision. resulting in 63 dB