Broadcast Sound Technology

Broadcast Sound Technology provides an explanation of the underlying principles of modern audio technology. Organized into 21 chapters, the book first describes the basic sound; behavior of sound waves; aspects of hearing, harming, and charming the ear; room acoustics; reverberation; microphones; phantom power; loudspeakers; basic stereo; and monitoring of audio signal. Subsequent chapters explore the processing of audio signal, sockets, sound desks, and digital audio. Analogue and digital tape recording and reproduction, as well as noise reduction, are also explained.

Foreword

Preface

Acknowledgments

1 Basic Sound

What are Sound Waves?

The Velocity of Sound Waves

Wavelength

2 The Behavior of Sound Waves

Reflection and Diffraction

The Inverse Square Law

Decibels

Measuring Sound Pressure

3 Aspects of Hearing

The Ear and the Hearing Process

The Ear's Response to Different Frequencies

Loudness and the Phone

4 Harming and Charming the Ear

Hearing Impairment

Pitch

Harmonics

Timbre

The Fallibility of the Ear

5 Room Acoustics

Sound Insulation

Room Resonances

6 Reverberation

Reverberation Time

Sabine's Formula

Optimum Reverberation Times

Sound Absorbers

7 Microphones

Transducers

Moving-Coil Microphones

Ribbon Microphones

Electrostatic Microphones

Electret and RF Electrostatic Microphones

Directional Characteristics

8 Phantom Power

'Standard Phantom', '48 V Phantom'

'Ά-Β Powering', 'Modulation Lead Powering'

9 Loudspeakers

The Radiating Surface

The Transducer

The Enclosure

Multiple Unit Loudspeakers

Specialized Loudspeakers

Listening Tests

10 Basic Stereo

How We Locate Sounds

Creating Artificial Time-of-Arrival Differences

Phase of Stereo Signals

Production of Stereo Signals

Coincident Pair Arrangements

Coincident Pairs and Panpots-Applications

Spaced Microphones

Compatibility: the M and S Signals

M/S Microphones

Headphones and Stereo

Transmission of Stereo (Radio)

11 Monitoring the Audio Signal

The Dynamic Range of an Audio Signal

Zero Level

The VU (Volume Unit) Meter

The PPM (Peak Program Meter)

Other Types of Program Measuring Device

Stereo PPMs

Interpreting Stereo PPM Readings

12 Processing the Audio Signal

Equalization

Compressor/Limiters

Noise Gates

13 Sockets and Symbols

Jacks and Sockets

Symbols

14 Sound Desks (Mixing Consoles)

The Basic Functions of a Sound Desk

A Typical Channel

Groups

Output Stages

'Echo'

PA and Foldback

Pre-Fade Listen (PFL) and after-Fade Listen (AFL)

Clean Feed

Multiway Working

Deriving Mono from Stereo

Communications

Computer Assisted Mixing (CAM)

Assignable Facilities

15 Digital Audio

Sampling

Quantizing

Bits (Binary Digits)

Bit-Rate (Bits Per Second)

Error Detection

16 Further Digits

Time Division Multiplex (TDM)

Bit-Rate Reduction

Basic Sound-in-Syncs (SiS)

NICAM 728

17 Analogue Tape Recording and Reproduction

The Recording Process

The Replay Process

Record and Replay Equalization

Azimuth

Full-Size Professional Machines

Cassette Machines

Cartridge Machines

Track Formats

18 Digital Recording and Reproduction

Principles of Digital Tape Recording and Replay

The DASH System

R-DAT

The Future of Tape Recording?

Compact Discs

Oversampling

19 Noise Reduction

Dolby A

Dolby B

Dolby C

Dolby SR ('Spectral Recording')

dbx

Telecom c4

20 Public Address

Public Address or Sound Reinforcement?

Requirements of PA

The Problem of Howlround

The Choice and Siting of Loudspeakers

Choice of Microphones

Electrical Processing of The Audio Signal

The PA Mixer

21 More Uses of Digits

Reverberation or Echo?

Artificial Reverberation

Digital Delay

Pitch Change

Digital Sound Desks (Digital Mixing)

Sampling

Digital Editing

Time Code

MIDI (Musical Instrument Digital Interface)

Further Reading

Index