Reverberation 

Reverberance is linked to the speed at which sound energy disappears in a room. An unfurnished room with hard surfaces, such as a church, is perceived as being more reverberant than a well-furnished living room.

The reverberation time is usually defined as the time it takes for sound to decrease by 60 dB.

Speech Clarity

Speech clarity concerns the quality of speech transfer to the listeners. In a reverberant room with disturbing background noise, it can be difficult to pick up speech. 

Auditory Strength

Auditory strength is the level at which we experience sound. A reverberant room gives a higher sound level than a room with added sound absorption.

Spatial Decay

The sound level decreases as the distance from the sound source increases. The design of the room (shape, furnishing, surface finish etc.) influences the extent to which the sound level decreases along with the distance.