Newsletters Local sites Contact Offices Library About Us HOME APPLICATIONS Airport Noise Building acoustics Room acoustics About Reverberation Time What is room acoustics? Data recording and analysis Environmental noise and vibration Machine Diagnostics Material testing Noise source identification Occupational health Pass-by noise testing Production testing PULSE Solutions Repetitive testing Sound power Sound quality Structural dynamics Telecom audio Vibration testing Urban noise PRINT About Reverberation Time Sound Level Versus Reverberation Time Sound level is the most important parameter to measure when solving environmental or occupational noise problems. In the open air (or the anechoic room) it is often all you need to measure. But indoors, the Reverberation Time (RT) affects not only whether you can understand what others say or enjoy music, but also the level and distribution of sound. The problem is usually that the RT is too long, but it may also be too short or not properly balanced over the frequency spectrum. Getting the RT Right Reverberation time that is too long will muffle speech sounds so that one sound (or word) cannot be distinguished from another, making it impossible to understand what is being said. This is critical in classrooms, auditoriums, churches, theatres and airport buildings. On the other hand, reverberation time that is too short will make levels too low at a distance, and make the sound too "dry". The optimal RT for music depends on the type of music and the volume of the room. Church music requires 2-4 seconds while concert studios need 1-2 seconds. The RT frequency spectrum should be reasonably flat and even. Excessive RT will cause the sound level to rise, causing annoyance or risk of impaired hearing. Typical examples are concrete stairwells in apartment blocks or workplaces with hard reverberant walls. RT in Practice Reverberation time is measured using either interrupted noise (pink or white) from a loudspeaker source, or impulsive noise from a starting pistol. It is measured in 1/1- or 1/3-octaves, serially or simultaneously. It is usually averaged over several positions in the room and over several decays in each position. Quite often a wide-band average is calculated by mathematically averaging the RT for a range of frequency bands. For critical applications, the shape of the decay curve is also important. Deviations from the straight line can reveal acoustical defects. PRINT Markets Products Applications Service Courses News & Events Login We help our customers measure and manage the quality of sound and vibration in their products and in the environment Brüel & Kjær Sound & Vibration Measurement A/S. P +45 77 41 20 00. F +45 45 80 14 05. info@bksv.com Copyright © Brüel & Kjær. All Rights Reserved. Corporate Information Privacy Policy Legal Notices We use cookies We use cookies to improve the usability of our website, to improve the accessibility of the content, and for statistical analysis. By continuing to browse this site, you accept our use of cookies. Read more about our cookie policy