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3 Posts in this encyclopedia categoryDecibel
The decibel (dB) unit specifies the sound pressure level on a logarithmic scale. The sound pressure level determines a sound’s loudness. As it is a logarithmic value, which means that a sound increasing by 10 dB is perceived as approximately twice as loud. Noise with more than 90 dB presents the risk of hearing damage.
Diffuse sound
Diffuse sound (or room noise R) consists of sound waves that, at the time of measurement or perception, have already been reflected several times by walls or other obstacles.
Direct sound
Direct sound D consists of sound waves that have not yet been reflected by an obstacle but are travelling directly from the source to the ear/measurement instrument.