What is the relationship between RT60 and STI?

What is the relationship between RT60 and STI?

• A. RT60 And STI Are Independent
• B. Longer RT60 Generally Yields Lower STI
• C. Longer RT60 Generally Yields Higher STI
• D. STI Defines RT60

Answer: (B)

In room acoustics, reverberation time (RT60) describes how long sound persists after the source stops. Speech Transmission Index (STI) measures how intelligible speech is in that space. When RT60 is longer, sound energy lingers and echoes smear the temporal and spectral cues that help us distinguish consonants and syllables. This overlap makes speech harder to understand, so STI drops. In short, longer RT60 generally yields lower STI. Think of it this way: a small, quiet classroom with a short RT60 lets speech come through clearly, giving a higher STI. A large, reverberant hall with a long RT60 blurs speech and reduces intelligibility, lowering STI. It’s important to remember STI and RT60 are related but not the same; RT60 isn’t defined by STI, and other factors like noise and the direct-to-reverberant ratio also influence STI.

In room acoustics, reverberation time (RT60) describes how long sound persists after the source stops. Speech Transmission Index (STI) measures how intelligible speech is in that space. When RT60 is longer, sound energy lingers and echoes smear the temporal and spectral cues that help us distinguish consonants and syllables. This overlap makes speech harder to understand, so STI drops. In short, longer RT60 generally yields lower STI.

Think of it this way: a small, quiet classroom with a short RT60 lets speech come through clearly, giving a higher STI. A large, reverberant hall with a long RT60 blurs speech and reduces intelligibility, lowering STI. It’s important to remember STI and RT60 are related but not the same; RT60 isn’t defined by STI, and other factors like noise and the direct-to-reverberant ratio also influence STI.