Acoustics


 * ACOUSTICS**



The travelling of sound measured in meters by second (m/s) Is the number of waves that pass a point per second, this is measured in Hertz (Hz) Is the distance between matching points on a wave, this is sometimes called Lambda and it is measured in meters (m) Longitudinal waves vibrate parallel to the direction of travel of the wave. Sound waves are longitudinal. Transverse waves vibrate at right angles to the direction of travel.
 * Speed **
 * Frequency**
 * Wavelength**
 * Longitudinal**
 * Transverse**


 * About the video **

-Sound is normally caused by objects vibrating

- Is variations in pressure what gives you a sound wave

- when we clap our hands you can see that they vibrate quite a lot, but this is actually the source of noise, you are creating acceleration noise. The air between our hands creates a little compression wave (witch is an acoustic wave, it's what we hear)

- if waves are above of the speed of sound, these waves get bunch together and eventually form a shockwave, witch is the sonic boom your hear
 * Reverbarance ** : is linked to the speed at which sound energy disappears in a room. An unfurnished room with hard surfaces, such as a church, is perceived as being more reverberant than a well-furnished living room.

What are room acoustics? Room acoustics are about the way in which sound behaves in a room. Sound transmission, sound absorption, sound reflection and sound diffusion are all aspects that are important here. Room acoustics also include how we as humans perceive different acoustic phenomena. The field of building acoustics covers sound insulation too, where the route that the sound takes from the room to other areas is included.

** What do you as an architect need to consider regarding Room Acoustic Comfort™? **

In many environments where people are present and communicate, high sound levels are perceived as one of the most disturbing factors. High noise levels have a negative effect on us and affect health, communication, safety, economy (effectiveness/productivity), learning and general wellbeing.

It is therefore important that you as an architect remember that room acoustic comfort does not only involve a certain reverberation time. To reduce sound levels, it is important to consider other descriptors that are directly linked to sound levels, such as Strength (G).

- Added absorption and how it is placed - The quantity and placing of sound-scattering objects such as furniture, shelves etc. - The size and shape of the room
 * The reverberation time is decided by: **

- The amount of absorption
 * The sound level is essentially determined by: **

- Early sound reflections in relation to late sound reflections - Background noise
 * Clarity of speech is essentially determined by: **

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.

Give priority to the different acoustic properties such as reverberance, speech clarity and sound level, depending on what the room is used for.

For example: · Sound level reduction will be most important in a kindergarten. · In a music room, the response of the room in the form of reverberance can be the most important aspect. · In a teaching situation, it is important to give priority both to speech clarity and to reduction of sound level. · In an open office landscape, it is essential that the sound propagation is restricted in order to minimize disturbance, mainly between different work groups. It is important that the sound level falls quickly with distance.

The room acoustic descriptors are guidance for achieving the desired acoustic function and for ensuring room acoustic comfort where people, and what they do, are put in focus.

** What must you as an architect do to achieve Room Acoustic Comfort™? **

In many of the commonly occurring types of rooms that we talk about here, a sound-absorbing ceiling is a practical aid for achieving Room Acoustic Comfort™ (RAC™). The ceiling’s sound-absorbing properties are described in sound absorption classes (A-E) in an international standard. Class A is the highest level of sound absorption.
 * 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.