The Effect of room acoustics on the prerceived acoustics of reproduced sound

Recordings of music, speech or other sounds have acoustical properties, such as reverberation, definition and clarity. For educational, engineering or entertainment purposes these recordings are often played back through loudspeakers in listening rooms, such as classrooms, recording studios or cinemas. The acoustical properties of a listening room affect the perceived acoustics of the recording (room in room acoustics), which may make an accurate reproduction or demonstration of the recording’s acoustical properties impossible. To find the practical impact of room in room acoustics, combinations have been investigated of room acoustic impulse responses using convolution techniques. The resulting change in an acoustical property is assumed to be accurate if it does not exceed the JND (Just Noticeable Difference). It is found that to accurately reproduce a steady sound energy decay rate (related to the reverberation time), the playback room is allowed to have as much as half this decay rate, under diffuse sound field conditions. For energy modulations (related to speech intelligibility) this decay rate should be more than four times smaller. Finally, initial energy ratios (related to definition and clarity) require auditive judgement in the direct soundfield