How Room Acoustics Are Measured
Optimizing room acoustics requires a detailed analysis of each space, as every room has unique acoustic characteristics. Additionally, various national and international standards guide the design process to ensure legal compliance and optimal sound quality. At Yamamah Smart, we specialize in assessing and improving acoustic performance to meet these standards while creating comfortable environments.
Comprehensive Room Analysis
Every object in a room—from walls and ceilings to furniture—affects its acoustic behavior. A proper analysis of the room’s current state is essential to determine the type and quantity of acoustic materials required to achieve the desired acoustic performance. This target can be set by legal standards, industry guidelines, or client requirements.
Traditionally, hiring an acoustician to develop a room acoustic concept can be time-consuming and costly. Some specialists work independently or represent specific manufacturers, which may limit material options. While consulting a dealer may provide multiple product choices, initial concepts are often rough estimates rather than precise calculations. Without proper planning, retrofitting may be necessary after installation, increasing costs.
At Yamamah Smart, we combine professional acoustic planning with the flexibility to select from a wide range of high-quality materials. This ensures the room achieves optimal sound performance without additional retrofitting.
Reverberation Time (RT60)
What is it?
Reverberation time (T) measures how long it takes for a sound to decay by 60 decibels after the source stops emitting. It is frequency-dependent, as different materials—such as stone, wood, textiles, and carpets—absorb sound at different rates. RT60 depends on the surface areas, absorption properties, and volume of the room.
How is it measured?
Using Sabine’s formula, reverberation time can be calculated mathematically:
T = 0.16 \times \frac{V}{A}
Where V is the room volume in cubic meters and A is the sum of all absorption surfaces in square meters, weighted by their sound absorption coefficients.
Why is it important?
Excessive reverberation can negatively impact speech intelligibility. In conference rooms, classrooms, or open-plan offices, achieving the correct reverberation time is critical to ensure clear communication throughout the space.
Speech Transmission Index (STI)
What is STI?
The Speech Transmission Index measures how well speech can be understood in a room. Similar to a heat map, STI highlights areas where speech intelligibility is high or low, helping to target acoustic interventions effectively.
How is it measured?
STI testing involves transmitting synthetic speech signals and analyzing how clearly they are received in different areas of the room. External noise and sudden sounds can affect the measurement, so proper setup and timing are essential.
Ray Tracing
What is it?
Ray tracing is a simulation technique that maps how sound waves travel and reflect within a room. This allows precise placement of acoustic panels and materials to control echoes, reflections, and sound distribution.
Why is it useful?
In large spaces like lecture halls or seminar rooms, ray tracing ensures that people in the back rows hear the speaker as clearly as those in the front, with minimal echo or distortion. It also helps plan acoustic interventions before installation, reducing trial-and-error adjustments.
At Yamamah Smart, we combine on-site measurements, reverberation calculations, STI analysis, and ray-tracing simulations to provide tailored acoustic solutions. Our approach guarantees spaces that are not only legally compliant but also comfortable and functional for their intended use.
