BOOK_CONTENT
From Sound Insulation

1.1 Introduction

This opening chapter looks at aspects of sound fields that are particularly relevant to sound insulation; the reader will also find that it has general applications to room acoustics.

The audible frequency range for human hearing is typically 20 to 20 000 Hz, but we generally consider the building acoustics frequency range to be defined by one-third-octave-bands from 50 to 5000 Hz. Airborne sound insulation tends to be lowest in the low-frequency range and highest in the high-frequency range. Hence significant transmission of airborne sound above 5000 Hz is not usually an issue. However, low-frequency airborne sound insulation is of particular importance because domestic audio equipment is often capable of generating high levels below 100 Hz. In addition, there are issues with low-frequency impact sound insulation from footsteps and other impacts on floors. Low frequencies are also relevant to fa ade sound insulation because road traffic is often the dominant external noise source in the urban environment. Despite the importance of sound insulation in the low-frequency range it is harder to achieve the desired measurement repeatability and reproducibility. In addition, the statistical assumptions used in some measurements and prediction models are no longer valid. There are some situations such as in recording studios or industrial buildings where it is necessary to consider frequencies below 50 Hz and/or above 5000 Hz. In most cases it should be clear from the text what will need to be considered at frequencies outside the building acoustics frequency range.

1.2 Rooms

Sound fields in...

Copyright Carl Hopkins 2007 under license agreement with Books24x7

Products & Services
Soundproofing and Acoustic Materials
Sound proofing and acoustic materials are used to attenuate, deaden, or control sound and noise levels from machinery and other sources for environmental amelioration and regulatory compliance. 
Acoustic Horns
Acoustic horns are relatively low-frequency horns that produce vibration at frequencies that will loosen and clean soot or other undesirable particulate buildup on chimneys, catalyst beds, or other process vessels.
Audio Transducers and Buzzers
Audio transducers and buzzers are used in electronic equipment, toys and various warning devices as the sounding component.
Speakers
Speakers produce and transmit sounds carried by electrical or radio signals.  This product category is primarily for industrial and OEM speakers rather than those for home use.
Room Partitions
Room partitions are used to separate interior space for work or privacy.

Topics of Interest

2.1 Introduction When airborne sound from the human voice is transmitted from one room to another, the resulting vibration on the walls and floors in the receiving room is at a sufficiently low level...

1.1 Sound and Acoustics Defined In everyday conversational language, acoustics is a term that refers to the quality of enclosed spaces such as lecture and concert halls in regard to their effect on...

Overview The following list of acoustic Standards relate to the measurement and prediction of sound and vibration; these were current at the time of writing and are referenced in the text. The reader...

II. THEORY AND PRINCIPLES Nature of Sound Waves Sound waves are simply vibrations of the particles making up a solid, liquid, or gas. As an energy form they are therefore an example of mechanical...

Acoustics is the science of sound and vibration. The control of sound and vibration transmission within a structure involves architectural design and structural, mechanical, and electrical engineering...