Architectural acoustics refers to the study and design of sound transmission in enclosed spaces. The acoustics of a room are its qualities related to sound transmission and reception.
In Chapter 3, we defined sound waves as longitudinal waves that travel in a solid, liquid, or gas. The most common path from source to receiver is through air, but not necessarily a direct path through the air. In a room, most of the sound waves that reach the listener's ear have been reflected by one or more surfaces of the room or by objects within the room. In a typical room, sound waves undergo dozens of reflections before they become inaudible.
It is not surprising, therefore that the acoustical properties of the room play an important role in determining the nature of the sound heard by a listener.
The subject of concert hall acoustics is of interest to both performers and serious listeners. Although to some the acoustic design of rooms seems to be "black magic", there are some very important principles that affect the way a room will respond to sound. Materials, shapes of walls, angles, all play a part in the acoustics of rooms.
In this chapter you will learn how to calculate reverberation time (an important element in room acoustics) and what contributes to good room acoustics.
As different as people are, so are the characteristics of a room as they relates to sound. Almost everything can have an effect on the way things sound from one room to another. Materials, shapes of walls, angles, all play a part in the acoustics of rooms.
It was one said that if bad sound were lethal the whole world would be dead. This specifically applies to electronic sound reinforcement. A well-designed sound system for speech will be loud enough, intelligible, provide uniform coverage, and not feed back.
In this chapter, we will look at the need for electronic sound reinforcement in large auditoriums and the principles by which a good system is designed.
In this chapter, we will look at the acoustics of small rooms. Listening rooms are the weakest link in the high fidelity sound system. In order to better understand the acoustics of rooms, we will discuss room resonances; the relationship of reverberant to direct sound; the variation of loudspeaker power level (Lw) and directivity factor Q with frequency; sound images from multiple sound sources; placement of loudspeaker and furniture; and program material.
The acoustics of small rooms differs substantially from the acoustics of large rooms. Reverberation time is the most important property of large room acoustics, whereas room resonances (modes) dominate small room acoustics. Small room acoustics is important in the design of classrooms, music listening rooms, and recording studios.