Common Acoustic Terms

• Decibel (dB): A unit used to measure the intensity of sound. It is a logarithmic scale, meaning an increase of 10 dB represents a tenfold increase in sound intensity.

• Sound Transmission Class (STC): A rating that measures how well a building partition attenuates sound. Higher STC ratings indicate better soundproofing capabilities.

• Noise Reduction Coefficient (NRC): A measurement of a material's ability to absorb sound, represented as a number between 0 and 1. Higher NRC values indicate greater sound absorption.

• Frequency: The number of vibrations or cycles per second of a sound wave, measured in Hertz (Hz). Higher frequencies are associated with higher pitches.

• Reverberation Time (RT): The time it takes for sound to decay by 60 dB after the source has stopped. It affects the clarity of sound in a space.

• Sound Pressure Level (SPL): A measure of the pressure variation in a sound wave, usually expressed in dB. It quantifies the loudness of sound.

• Acoustic Insulation: Materials used to reduce sound transmission between spaces, improving soundproofing and sound quality.

• Direct Sound: Sound that reaches the listener directly from the source, without any reflections or delays.

• Diffusion: The scattering of sound waves in various directions, which helps improve sound quality in a space.

• Absorption: The process by which sound energy is converted into heat or another form of energy when it encounters a material.

Conclusion

Understanding these acoustic terms is essential for anyone involved in sound design, architecture, or acoustics. This glossary serves as a reference to help you navigate the technical language of the acoustic field.