Sound engineering explained 2nd

Contents Preface xi Acknowledgements xiii About this book xv 1 Sound waves 1 Part 1 1 What are sound waves? 1 Frequency 2 Wavelength 2 Amplitude 2 The velocity of sound waves 3 Velocity, frequency and wavelength 3 Sound waves and obstacles 4 The bending of sound waves (diffraction) 5 Units used in sound 6 Sound intensity and the effect of distance 9 Decibels 10 Part 2 11 The velocity of sound waves 11 Units 12 Decibels 12 2 Hearing and the nature of sound 14 Part 1 14 The response of the ear 14 Loudness. The dB(A) 15 Musical pitch 16 1111 2 3 4 5 6 7 8 9 1011 1 2 31111 4 5 6 7 8 9 20111 1 2 3 4 5 6 7 8 9 30111 1 2 3 4 5 6 7 8 9 4011 1 2 31111 Musical quality (‘timbre’) 18 The brain’s perception of sound 19 Part 2 22 Pitch 22 Frequency ranges in music 22 ‘False bass’ 23 3 Basic acoustics 25 Part 1 25 Sound isolation 25 Internal acoustics 29 Part 2 35 Sound isolation 35 Sound absorption 35 4 Microphones 40 Part 1 40 Microphone transducers 40 Polar responses 44 ‘Boundary’ microphones 48 Personal microphones 48 Radio microphones (‘wireless microphones’) 48 Part 2 51 Electrostatic microphones 51 Production of the different polar responses 52 Sensitivities of microphones 56 Phantom power 57 Balanced wiring 58 Radio microphone data 59 5 Using microphones 61 Objectives and problems in recording 61 Specific applications of microphones 66 6 Monitoring 71 Part 1 71 Technical monitoring 71 Aural monitoring 75 Listening tests 80 vi Contents Part 2 82 Reference voltages in audio signals 82 PPMs and VU meter readings 83 Helmholtz resonators 84 Loudspeaker power 85 Loudspeaker cables 86 Professional and domestic standards 87 7 Stereo 88 Part 1 88 How stereo works 88 Methods of producing inter-channel differences 90 Terminology 91 Stereo listening 92 Stereo loudspeaker matching 94 Phase 94 Part 2 97 Microphone techniques for stereo 97 Headphones for stereo monitoring 102 8 Sound mixers 104 Part 1 104 Terminology 1005 The basic channel 105 Important features of any mixer 107 Output stage 111 Part 2 113 Inputs and connections 113 Equalization 116 Public Address and Foldback (PA and FB) 119 Talkback 121 9 Controlling levels 123 Manual control of levels 123 Electronic level control 127 Noise gates 131 10 Digital audio 133 Part 1 133 Historical 133 Basic principles 133 Other applications of digital audio 139 1111 2 3 4 5 6 7 8 9 1011 1 2 3 4 5 6 7 8 9 20111 1 2 3 4 5 6 7 8 9 30111 1 2 3 4 5 6 7 8 9 4011 1 2 31111 Contents vii MIDI 142 Data compression 143 Additional terminology 143 Part 2 145 Compact discs 145 Error correction 147 Cleaning CDs 148 Cost of CD players 148 NICAM 148 A little more about error correction 150 11 Recording 151 Part 1 – Recording devices and systems 151 Analogue recording 151 The fundamentals of magnetic recording 152 Cassette quality 153 Noise reduction 154 Head and tape cleanliness 155 Digital recording 156 DAT 157 MiniDisc® 157 Solid state recording 158 MP3 159 Part 2 – Editing 160 Why edit? 160 Practicalities 161 Editing tape 162 Digital tape editing 162 MiniDisc editing 163 12 Public address 164 Part 1 164 Outdoor PA 165 Indoor PA 165 Part 2 167 Howl-rounds 167 100-volt systems 168 viii Contents 13 Music and sound effects 170 Music 170 Sound effects 171 14 Safety 175 Electrical safety 175 Noise and hearing 178 ‘Mechanical’ safety 179 Fire 181 Copyright 184 Miscellaneous data 185 Further reading 189 Answers 191 Index 195