Two Different Kinds of Sound Reflection

Sound bounces around a hard surfaced room in all directions. Add multiple groups of people all trying to talk to each other, and the noise floor quickly rises to deafening levels. As each party has to talk louder to be heard, the noise rises. This is called, in acoustical terms, the “Cocktail Party Effect”. For the purposes of noise control and speech intelligibility, sound reflection is either vertical or horizontal.

Horizontal Reflection:

As each separate conversation takes place in the room, sound reflects horizontally, jumping across the room. This is what we define as crosstalk. In some circumstances, it’s actually easier to hear the conversation from across the room, instead of the one right in front of you.

Any large, flat ceiling will reflect sound horizontally, including T-bar ceilings. Add polished hard floors and large areas of glass, and the reflection is magnified exponentially. Slow down the horizontal sound reflections through ceiling-mounted, distributed absorption and diffusion.

Vertical Reflection:

This is the reflection we want to retain, as this creates a bright ambiance. Even though each party hears a good amount of direct sound, without the vertical room reflection, it would sound hushed and two dimensional. This is not desirable in most venues except perhaps libraries

The ideal acoustic approach seeks to retain as much vertical reflection of vocal frequency sound as possible.

ASC Acoustic Coffered Ceiling:

Applied to the ceiling in a grid pattern, the acoustic effect is a calmer, yet locally lively sound within the room.