Reverberation Time (RT60) – Definition & Detailed Explanation – Audio Terms Glossary

What is Reverberation Time (RT60)?

Reverberation Time (RT60) is a measure of the time it takes for sound to decay by 60 decibels after the sound source has stopped. In simpler terms, it is the time it takes for a sound to fade away in a room after the source of the sound has stopped. Reverberation Time is an important factor in determining the acoustics of a space and can greatly impact the overall sound quality.

How is Reverberation Time (RT60) measured?

Reverberation Time is typically measured using a sound level meter and a loudspeaker. A loud sound is produced in the room, and the sound level meter records the sound as it decays over time. The time it takes for the sound to decrease by 60 decibels is then calculated to determine the Reverberation Time. This measurement is usually done at multiple frequencies to get a more accurate representation of the room’s acoustics.

What factors affect Reverberation Time (RT60)?

Several factors can affect the Reverberation Time of a room, including the size and shape of the room, the materials used in the construction of the room, the presence of sound-absorbing materials such as carpets or curtains, and the amount of furniture and other objects in the room. Larger rooms with hard, reflective surfaces tend to have longer Reverberation Times, while smaller rooms with softer, absorbent materials tend to have shorter Reverberation Times.

How does Reverberation Time (RT60) impact sound quality?

Reverberation Time can have a significant impact on the overall sound quality in a room. A longer Reverberation Time can make sounds blend together and create a more immersive listening experience, especially in large concert halls or auditoriums. However, too much reverberation can also make speech difficult to understand and music sound muddy. On the other hand, a shorter Reverberation Time can make speech clearer and music more defined, but it can also make the room sound dry and lifeless.

What are the different categories of Reverberation Time (RT60)?

Reverberation Time is typically categorized into four main categories: short, medium, long, and very long. Short Reverberation Times are usually less than 1 second and are commonly found in small rooms with a lot of sound-absorbing materials. Medium Reverberation Times are between 1-2 seconds and are often found in medium-sized rooms with a mix of reflective and absorbent surfaces. Long Reverberation Times are between 2-3 seconds and are common in larger rooms with mostly reflective surfaces. Very long Reverberation Times are over 3 seconds and are typically found in large concert halls and cathedrals.

How can Reverberation Time (RT60) be adjusted or controlled?

There are several ways to adjust or control the Reverberation Time of a room. Adding sound-absorbing materials such as carpets, curtains, and acoustic panels can help reduce the Reverberation Time and make the room sound clearer. Rearranging furniture and adding soft furnishings can also help absorb sound and reduce reverberation. Additionally, adjusting the volume and placement of sound sources can help control the amount of reverberation in a room. In some cases, electronic devices such as digital reverberation processors can be used to artificially adjust the Reverberation Time of a room.