Contents
About the author
Acknowledgements
Preface
Introduction
Chapter 1 General requirements and common errors
1.1 The general requirements
1.2 Sound isolation and background noise levels
1.2.1 From the inside out
1.2.2 From the outside in
1.2.3 Realistic goals
1.2.4 Isolation versus artistry
1.3 Confidence in the system
1.4 The complete system
1.5 Very common mistakes
1.5.1 The need for space
1.5.2 Height
1.5.3 Floor loading
1.6 Summary
Chapter 2 Sound, decibels and hearing
2.1 Perception of sound
2.2 Sound itself
2.3 The decibel; sound power, sound pressure and sound intensity
2.3.1 The dBA and dBC scales
2.4 Human hearing
2.4.1 Chacun A Son Oreille
2.5 Summary
References
Bibliography
Chapter 3 Sound isolation
3.1 Vibrational behaviour
3.1.1 Relevance to isolation
3.2 Basic isolation concepts
3.2.1 Damping and the mass law
3.2.2 Floating structures
3.2.3 Floating system choices
3.3 Practical floors
3.3.1 Floors on weak sub-floors
3.4 Ceiling isolation
3.4.1 A trip through the ceiling
3.5 Summing the results
3.5.1 Internal reflexions
3.6 Wall isolation
3.7 Lighter weight isolation systems
3.8 Reciprocity and impact noises
3.9 The distance option
3.10 Discussion
3.11 Summary
Reference
Bibliography
Chapter 4 Room acoustics and means of control
4.1 Internal expansion
4.2 Modes
4.3 Flutter echoes and transient phenomena
4.4 Reverberation
4.4.1 Measuring reverberation time
4.5 Absorption
4.5.1 Speed of sound in gases
4.5.2 Other properties of fibrous materials
4.5.3 Absorption coefficients
4.5.4 Porous absorption
4.5.5 Resonant absorbers
4.5.6 Membrane absorbers
4.6 Q and damping
4.7 Diffusion
4.8 Diffraction
4.9 Refraction
4.10 Review
4.11 Summary
References
Bibliography
Chapter 5 Designing neutral rooms
5.1 Background
5.2 Large neutral rooms
5.3 Practical realisation of a neutral room
5.3.1 Floors
5.3.2 Shapes, sizes and modes
5.3.3 From isolation shell towards neutrality
5.3.4 Lower frequency control
5.3.5 Relative merits of neutrality and idiosyncrasy
5.4 What is parallel?
5.5 Reflexions, reverberation and diffusion
5.6 Floor and ceiling considerations
5.7 Wall treatments
5.8 Small and neutral
5.8.1 Practical constructions
5.8.2 The journey of the sound waves
5.8.3 The pressure zone
5.8.4 Wall losses
5.8.5 Transfer of sound between high and low densities
5.8.6 Combined effects of losses
5.8.7 A micro-problem
5.9 Trims
5.10 The degree of neutrality – an overview
5.11 Summary
References
Bibliography
Chapter 6 Rooms with characteristic acoustics
6.1 Definitions
6.2 A brief history of idiosyncrasy
6.2.1 From a room to a classic
6.2.2 Limited, or priceless?
6.3 Drawbacks of the containment shells
6.4 Design considerations
6.4.1 Room character differences
6.5 Driving and collecting the rooms
6.6 Evolution of stone rooms
6.6.1 Construction options
6.7 Live versus electronic reverberation
6.8 The 20% rule
6.9 Reverberant rooms and bright rooms – reflexion and diffusion
6.9.1 Bright rooms
6.10 Low frequency considerations in live rooms
6.11 General comments on live rooms
6.12 Orchestral rooms
6.12.1 Choice of venues, and musicians’ needs
6.13 RT considerations
6.14 Fixed studio environments
6.15 Psychoacoustic considerations and spacial awareness
6.16 Dead rooms
6.17 Summary
References
Bibliography
Chapter 7 Variable acoustics
7.1 The geometry of change
7.2 Small room considerations
7.3 Summary
Chapter 8 Room combinations and operational considerations
8.1 Options and influences
8.1.1 Demands from control rooms
8.2 Layout of rooms
8.2.1 Priorities and practice
8.3 Isolation considerations: doors and windows
8.3.1 Sliding doors
8.3.2 Window systems
8.3.3 Multiple glazing considerations
8.3.4 High degrees of isolation
8.4 The Geddes approach
8.5 Recording techniques for limited acoustics
8.5.1 Moving musicians and changing microphones
8.6 A compact studio
8.7 Review
8.8 Summary
References
Chapter 9 The studio environment
9.1 Some human needs
9.1.1 Daylight
9.1.2 Artificial light
9.1.3 Ease and comfort
9.2 Ventilation and air-conditioning
9.2.1 Ventilation
9.2.2 Air-conditioning systems and general mechanical noises
9.3 Headphone foldback
9.3.1 Loudspeaker foldback
9.4 Colours, and general decoration
9.5 AC mains supplies
9.5.1 Phase
9.5.2 Power cabling
9.5.3 Balanced power
9.5.4 Mains feeds
9.5.5 Earthing
9.6 Summary
References
Chapter 10 Limitations to design predictions
10.1 Room responses
10.1.1 The envelope of the impulse response, and reverberation time
10.1.2 Schroeder plots
10.1.3 Energy/time curves
10.1.4 Waterfall plots
10.1.5 Directional effects
10.2 Scale models
10.3 Computer models
10.4 Sound pulse modelling
10.5 Light ray modelling
10.6 Ripple tank modelling
10.7 Review
10.8 Summary
References
Chapter 11 Loudspeakers in rooms
11.1 From the studio to the control room
11.2 Room influences
11.2.1 Radiation patterns
11.2.2 Loading by boundaries
11.2.3 Dipole considerations
11.2.4 Diffraction sources
11.3 Room reverberation and the critical distance
11.4 Sound power radiation
11.5 Corrective measures
11.5.1 Minimum and non-minimum phase
11.5.2 Digital correction techniques
11.5.3 Related problems in loudspeaker
11.5.4 Summary of correct applications of equalisation
11.6 Phase and time
11.7 The black art
11.8 Summary
Bibliography
Chapter 12 Flattening the room response
12.1 Electronic correction concerns
12.2 The standard room
12.3 The anechoic chamber
12.4 The hybrid room
12.5 A BBC solution
12.6 On listening rooms in general
12.7 Close-field monitoring
12.8 Summary
References
Chapter 13 Control rooms
13.1 The advent of specialised control rooms
13.1.1 Geometrically controlled rooms
13.1.2 Directional dual acoustics
13.1.3 The LEDE
13.1.4 The Non-Environment
13.1.5 Toyoshima rooms
13.2 Built-in monitors
13.3 Directional acoustics
13.4 Scaling problems
13.5 The pressure zone
13.6 One system
13.7 Aspects of small control room designs
13.7.1 Conflicting requirements
13.7.2 Active absorbers
13.8 A short overview
13.9 Summary
References
Bibliography
Chapter 14 The behaviour of multiple loudspeakers in rooms
14.1 Mono sources
14.2 Stereo sources
14.3 Steady-state performance
14.4 Transient considerations
14.5 The pan-pot dilemma
14.6 Limitations, exceptions and multi-channel considerations
14.7 Surround in practice
14.8 A general view
14.9 Summary
References
Bibliography
Chapter 15 Studio monitoring: the principal objectives
15.1 The forces at work
15.2 Where is the reference?
15.3 Different needs
15.4 What is right?
15.5 Close field monitoring
15.6 Why the NS10M?
15.7 General needs
15.8 Summary
References
Bibliography
Chapter 16 The Non-Environment control room
16.1 Introduction
16.2 Sources of uncertainty
16.3 Removing a variable
16.4 Limitations, real and imaginary
16.5 Spacial anomalies
16.6 Solutions
16.7 Stereo imaging constraints
16.8 The concept of stereo as currently used
16.9 Conflicts and definitions
16.10 A parallel issue
16.11 Prior art and established ideas
16.12 The zero option – the origins of the philosophy
16.13 Summary
References
Chapter 17 The Live-End, Dead-End approach
17.1 First impressions
17.2 A window of objectivity
17.3 Working and listening environments
17.4 Summary
References
Bibliography
Chapter 18 Response disturbances due to mixing consoles and studio furniture
18.1 The sound of mixing consoles
18.2 Equipment racks
18.3 Computer and video monitoring
18.4 Sofas
18.5 Effects and equipment racks
18.6 Close-field monitors
18.7 General commentary
18.8 Summary
Bibliography
Chapter 19 Objective measurement and subjective evaluations
19.1 Objective testing
19.1.1 Pressure amplitude responses
19.1.2 Harmonic distortion
19.1.3 Directivity
19.1.4 Acoustic source
19.1.5 Step-function response
19.1.6 The power cepstrum
19.2 The on-axis pressure amplitude response
19.3 Harmonic distortion
19.3.1 Intermodulation distortion
19.4 Directivity – off-axis frequency responses
19.5 Acoustic source
19.6 Step-function responses
19.7 Power cepstra
19.8 Waterfalls
19.9 General discussion of results
19.10 The enigmatic NS10
19.11 The NS10M – a more objective view
19.11.1 Specifications and measurements
19.11.2 Discussion of results vis-à-vis subjective perception
19.11.3 Conclusions
19.12 The noise of conflict
19.13 Summary
References
Chapter 20 Studio monitoring systems
20.1 The constituents of the system
20.2 Console monitor circuitry
20.3 Audio cables and connectors
20.4 Monitor amplifiers
20.5 Loudspeaker cables
20.6 Crossovers
20.6.1 Passive crossovers
20.6.2 Active crossovers
20.6.3 Crossover characteristics
20.6.4 Slopes and shapes
20.6.5 Digital crossovers
20.7 Loudspeaker cabinets
20.7.1 Cabinet mounting
20.7.2 Cabinet concepts
20.7.3 Mounting practices and bass roll-offs
20.8 Loudspeaker drive units
20.8.1 Low frequency driver considerations
20.8.2 Efficiency and sensitivity
20.8.3 Magnet systems and cone materials
20.8.4 High frequency loudspeakers
20.8.5 Mid-range loudspeaker
20.8.5.1 Cone drivers
20.8.5.2 Dome drivers
20.8.5.3 Mid range horn loudspeakers
20.9 Review
20.10 Summary
References
Bibliography
Chapter 21 Surround sound and control rooms
21.1 Surround in the cinemas
21.2 TV surround
21.3 Music-only surround
21.4 An interim conclusion
21.5 The psychoacoustics of surround sound
21.6 Rear channel concepts
21.7 Perceived responses
21.7.1 The simple discrete source
21.7.2 The multiple distributed source
21.7.3 Dipole surround loudspeakers
21.7.4 Diffuse sources
21.8 Low frequencies and surround
21.8.1 Music-only low frequencies
21.9 Close-field surround monitoring
21.10 Practical design solutions
21.10.1 The choice of rear loudspeakers
21.11 Other compromises, other results
21.12 Summary
References
Bibliography
Chapter 22 Human factors
22.1 The ambiance of the occasion
22.2 The subjectivity of monitoring
22.3 Conditioning and expectations
22.4 Lack of reference points in human judgements
22.5 Studios and control rooms
22.6 Summary
References
Chapter 23 A mobile control room
23.1 The problems to be solved
23.1.1 Electronic control limitations
23.1.2 Space problems
23.2 The vehicle
23.3 Acoustic discussion
23.3.1 Rear wall absorber
23.3.2 Frequency breakdown
23.3.3 Side wall reflexions
23.4 Close-range monitoring
23.5 Directivity and total power
23.6 Attaching a sub-woofer
23.6.1 The appropriate equalisation
23.7 Results
23.8 Conclusions
23.9 Summary
References
Appendix 1
Appendix 2
Appendix 3
Glossary of terms
Index
