RT60 Explained: Understanding Reverberation Time

When evaluating how sound behaves in a room, one of the most important measurements is RT60. It gives us an objective way to describe reverberation, which has a huge impact on clarity, tonal balance, and overall listening quality.

What Is RT60?

RT60 stands for Reverberation Time, 60 decibels. It measures how long it takes for sound to decay by 60 dB after the original source stops.
    •    A short RT60 (fast decay) means the room sounds tight and controlled with minimal echo.
    •    A long RT60 (slow decay) means the room is more reverberant, with sound lingering and overlapping.

In practice, most listening rooms aim for a balanced RT60 that avoids both extremes.

Why It Matters

RT60 directly affects how you hear music and movies:
    •    Speech Intelligibility: Too much reverberation makes dialogue hard to understand.
    •    Clarity of Music: Long decay times blur details and reduce accuracy.
    •    Bass Control: Low frequencies often have much longer decay times, which can make bass sound muddy.

Measuring RT60

Tools like Room EQ Wizard (REW) or professional acoustic analyzers can measure RT60 in your space. If needed, consulting an acoustician can provide a precise treatment plan.

Improving RT60

If your RT60 is too long, the solution is usually acoustic treatment:
    •    Absorbers to reduce excessive reverberation
    •    Bass traps to shorten low-frequency decay
    •    Diffusers to spread energy evenly without deadening the sound