Speech intelligibility is a critical component of any space where the communication through speech is the primary function of the space. This includes churches, schools, lecture theatres, drama theatres, and even airports, train stations, bus stations and cruise ship terminals. Speech intelligibility is not just a function of sound system use, it can be measured even when there is no sound system involved.

The factors that influence speech intelligibility: reverberation time, reflections, background noise and bandwidth can be tested with or without a sound system. Many poorly designed sound systems can actually degrade the speech intelligibility in a difficult space. We can provide both acoustical design and sound system design to optimize speech intelligibility. This is becoming increasingly important for meeting disability access guidelines for the hearing impaired, or for schools with a high percentage of students with English as a second language.

We can evaluate existing conditions, providing a measure of STI (Speech Transmission Index) or %ALCONS (Percentage Articulation Loss of Consonants), and develop recommendations to improve the acoustical and sound system performance.

Why does excess reverberation affect speech intelligibility?