Acoustics

Acoustics


 * Speed: distance travelled in unit time
 * Frequency: is the number of waves that pass a point per second. It is measured in Hertz.
 * Wavelength: is the distance between matching points on a wave. This is sometimes called Lambda and it is measure in metres (m)
 * Longitudinal: vibration parallel to the direction of travel of the wave.
 * Transverse: vibration at right angels to the direction of travel of the wave.

NOTES:

Room Acoustic Comfort™ (RAC™) means that, when performing an evaluation of room acoustics, it is important to take into account different types of rooms and what people do there.

**The ceiling’s effect on different acoustic descriptors:**

**Reverberation time:** The sound-absorbing ceiling will interact with the sound-dispersing (scattering) furnishings in the room. The more sound-dispersing (scattering) objects there are, the greater the benefit of the ceiling. In a sparsely furnished room, the reverberation time can be long as the sound energy lingers between sound-reflecting walls.

**Sound level:** The sound level that is constantly generated in the room will, on the other hand, be effectively dealt with by the ceiling and be less dependent on sound-dispersing (scattering) objects. A sound absorption class A product provides the most effective decrease of the sound level.

**Speech clarity:** Suspended ceilings have a positive effect on speech clarity by reducing the reverberance in the room. A good, effective, sound-absorbing ceiling contributes to a good relation between early and late sound reflections in such a way as to benefit speech clarity.

Simply put, there is positive sound and negative sound. The negative sound is unwanted and we call it noise. Noise can give rise to problems at levels far below those that can cause damage to hearing.

To create room acoustic comfort, it must be understood that a number of different factors influence the hearing experience. The comprehensive acoustic assessment of a room requires the measurement of several different parameters if the hearing experience is to be correctly reflected. This is a question of room acoustic descriptors that are linked to reverberance, speech clarity, auditory strength and spatial decay.

The shape, size, surface finish and furnishings of a room all determine its acoustic properties. Room acoustic design involves controlling these factors, thus influencing sound absorption, reflection, propagation and diffusion in order to support a certain type of function or activity

    

A computer lab for 30 students:

For this type of room, the best option to control the acoustic it would be an absorbent ceiling to try to absorb the more sound level possible. The furnishing should also be absorbent because in a computer lab the silence is required, although 30 students aren't a lot of people, they can make a lot of noise if they want. The speech isn't important in this case, because each student is going to work individually on their computers, however if a teacher speaks in the classroom the clarity is important too.