1.Architectural Acoustics

Architectural Acoustics

Classification of Sound : Loudness – Weber Fechner law - Decibel – Absorption Coefficient – Reverberation – Saline’s formula – Factors affecting acoustics of buildings and their remedies.

• now we are study about each of the topic and understand what is it.

Classification of sound

firstly what is sound-->Sound is a Vibration In an Elastic Medium With definite Frequency & Intensity.        
• Longitudinal wave . 
• requires a medium . 
• cannot travel in a vacuum.

 @ Now the audible sound have a two classification.

                     1.Musical Sound     2.Noise

Loudness

Weber Fechner law

From this relation it is seen that loudness is directly proportional to the logarithm of intensity and is know as a weber-Fechner law.

Absorption Coefficient

The sound absorption coefficient indicates how much of the sound is absorbed in the actual material. The absorption coefficient can be expressed as: 

α = I_a / I_i        (1)

where 

I_a = sound energy absorbed by the surface  (W/m²)

I_i = total sound energy incident on it (W/m²)

Reverberation

The persistence or prolongation of sound in a hall even though the source of sound is cut off is called reverberation.  

Reverberation Time:-The Time taken by the sound to fall below the minimum audibility level after the source stopped sounding is called reverberation Time.

Sabine’s formula