Have you ever attended an event, meeting, or worship service where you struggled to comprehend the words being spoken? There are many potential causes for this, but the two most common causes are a poor acoustic environment and a poorly designed sound system. The measure we utilize to determine how well a presenter is understood is called “Speech Intelligibility”.
Speech Intelligibility is defined as “a measure of how comprehensible speech is in given conditions”. In other words, how well can your presenter, performer, or emergency announcement be understood by your listener. Poor speech intelligibility can result in missed information or distractions for your listener. In the case of emergency announcement, this can be detrimental.
Imagine for a minute that a student you know is attending a pep rally in their high school gymnasium. During the rally, the principal makes an announcement over the gymnasium PA stating that “all students and staff should calmly exit the gymnasium immediately and exit single file through exterior doors 7 and 8 into the courtyard”. However, gyms typically perform poorly in acoustic testing due to their large size, hard parallel surfaces, and reflective materials (such as lacquered wood and painted brick). As a result, your our hypothetical student body missed the details of this message and the room erupted into chaos as students failed to understand the directions being given.
Now let’s imagine that this particular gymnasium is not only very reflective, but the integrated sound system also did not account for the speakers’ coverage patterns. As a result, every word spoken by the principal hits the listener’s ear from the speaker but then also hits the listener’s ear again (milliseconds later) from another speaker reflecting off the opposite wall. This effect is multiplied each time a reflection happens, resulting in a listener hearing each syllable repeated over the other syllables a multitude of times. Our brains are very good at ignoring unnecessary information, but when that information is louder or more present than the intended speech, we lose the messaging entirely.
Now let’s imagine that this same school implemented acoustic treatment in the space for absorption. As sound travels from the speakers through space, the acoustic panels absorb those reflections, lowering the intensity of the reflected sound, and ultimately making it easier to understand the principal’s message. Couple this with a sound system that is designed to direct sound off those reflective surfaces, and the result is crystal clear messaging even in a large, acoustically challenging space like a gymnasium.
Fortunately, audio-visual integrators (like Axent Solutions) are here to help design systems and treat spaces of all kinds (I’ve been in a conference room that had a 5-second decay time. Try to understand that video call from the far-end…), ensuring that your message is not only heard, but clearly understood.
If Axent Solutions can ever assist with a free evaluation of your spaces and integrated AV systems, please don’t hesitate to reach out!