Glenn recently presented a paper to the Institute of Acoustics in Bristol, United Kingdom at the Reproduced Sound Conference on the relationship between frequency response and the speech transmission index.
The key point to take away from our research and presentation is that when specifying or commissioning an emergency sound system in a road tunnel, blind adherence to simply achieving a STI performance without paying specific attention to the frequency response of the system over the entire listening area can yield a system that produces poor perceived intelligibly even though its performance meets the project specification.
Click here to find the paper authored by Glenn.