Description
Sound Pressure is measured in decibels (dB) and has a logarithmic scale. A difference of 10dB indicates a difference of 10 times the sound pressure level. As a rule of thumb, the sound pressure level drops by about 6dB every time the distance is doubled. The sound transmission class (STC), measured in dB, is the common measure by which acoustical performance is rated. It is a weighted average over the frequency range 100 to 5,000 Hz of the sound transmission loss (STL). See Sound Attenuation Charts.