This classic and authoritative textbook contains material that is not over-simplified and can be used to solve real-world noise control engineering problems. Engineering Noise Control, 6th edition covers theoretical concepts, and practical application of current noise control technology. Topics extensively covered or revised from the 5th edition include: beating; addition and subtraction of noise levels; combining multi-path noise level reductions; hearing damage assessment and protection; speech intelligibility; noise weighting curves; instrumentation, including MEMS, IEPE and TEDS sensors; noise source types, including transportation noise and equipment noise estimations; outdoor sound propagation, including noise barriers, meteorological effects and sloping ground effects; sound in rooms, muffling devices, including 4-pole analysis, self noise and pressure drop calculations; sound transmission through single, double and triple partitions; vibration measurement and control, finite element analysis; boundary element methods; and statistical energy analysis. Discusses all aspects of industrial and environmental noise control An ideal textbook for advanced undergraduate and graduate courses in noise control An excellent reference text for acoustic consultants and engineers Practical applications are used to demonstrate theoretical concepts Includes material not available in other books A wide range of example problems and solutions that are linked to noise control practice are available for download from www.causalsystems.com.

Understanding Active Noise Control Provides a concise introduction to the fundamentals and applications of active control of vibration and sound for the non-expert. It is also a useful quick reference for the specialist engineer. The book emphasises the practical applications of technology, and complex control algorithms and structures are only discussed to the extent that they aid understanding. Extensive recommendations for further reading on the subject are provided, but the text will stand alone for those seeking an overview of the key issues: fundamentals, control systems, transducers, applications and possible future directions.

This classic and authoritative textbook contains material that is not over-simplified and can be used to solve real-world noise control engineering problems. Engineering Noise Control, 6th edition covers theoretical concepts, and practical application of current noise control technology. Topics extensively covered or revised from the 5th edition include: beating; addition and subtraction of noise levels; combining multi-path noise level reductions; hearing damage assessment and protection; speech intelligibility; noise weighting curves; instrumentation, including MEMS, IEPE and TEDS sensors; noise source types, including transportation noise and equipment noise estimations; outdoor sound propagation, including noise barriers, meteorological effects and sloping ground effects; sound in rooms, muffling devices, including 4-pole analysis, self noise and pressure drop calculations; sound transmission through single, double and triple partitions; vibration measurement and control, finite element analysis; boundary element methods; and statistical energy analysis. Discusses all aspects of industrial and environmental noise control An ideal textbook for advanced undergraduate and graduate courses in noise control An excellent reference text for acoustic consultants and engineers Practical applications are used to demonstrate theoretical concepts Includes material not available in other books A wide range of example problems and solutions that are linked to noise control practice are available for download from www.causalsystems.com.

For readers with no background in acoustics Takes a unique problem based learning approach, reinforcing basic material with progressively complex example problems with solutions. Carefully up-dates and extended from the first edition Solutions to these additional problems available to instructors on request. Suits practising engineers with no acoustics background addressing noise problems in the workplace.

For readers with no background in acoustics Takes a unique problem based learning approach, reinforcing basic material with progressively complex example problems with solutions. Carefully up-dates and extended from the first edition Solutions to these additional problems available to instructors on request. Suits practising engineers with no acoustics background addressing noise problems in the workplace.

Contents:
Chapter One. A Little History. 1.1 Introduction. 1.2 Early history. 1.3 Later history 1.4 The future. Chapter Two: Foundations of Active Control. 2.1 Physical mechanisms 2.2 Basic structure of active noise Control systems. 2.3. Control system optimisation. 2.3.1 Influence of control source output power and placement. 2.3.2 Influence of error sensor placement. 2.3.3 Influence of reference signal delay and quality. Chapter Three: The Electronic Control System. 3.1 Introduction 3.2 Control Filter. 3.3 Cancellation path transfer function estimation. 3.4 Adaptation algorithms. 3.4.1 FXLMS algorithm for adapting the weights of an FIR filter. 3.4.2 Multi-channel and filtered-U RLS algorithms for IIR filters. 3.4.3 Genetic algorithms. 3.4.3.1 Killing selection instead of survivor selection. 3.4.3.2 Weight String Instead of Binary Encoding. 3.4.3.3 Mutation probability and amplitude 3.4.3.4 Rank-based selection 3.4.3.5 Uniform crossover 3.4.3.6 Genetic algorithm parameter adjustment 3.4.3.7 Performance measurement 3.5 Putting it all together 3.6 Important practical controller implementation issues 3.6.1 Microprocessor selection. 3.6.2 Converter type and group delay considerations 3.6.3 Digital sampling rate 3.6.4 Algorithm considerations 3.6.5 Accuracy of controller output. Chapter Four: Active Noise Control Sources. 4.1 Acoustic sources. 4.2 Vibration sources. Chapter Five: Error Sensors. 5.1 Microphones. 5.2 Vibration sensing and control of sound radiation 5.3 Sound intensity and energy density control. 5.4 Control algorithms for various sensing strategies. 5.4.1 Shaped or distributed structural sensors. 5.4.2. Sound intensity 5.4.3 Energy density. 5.4.4 Power or intensity squared. Chapter Six: Applications of Active Noise Control. 6.1 Some general considerations. 6.2 Application Examples. 6.2.1 Sound propagation in ducts. 6.2.2.1 Plane wave propagation 6.2.2.2 Higher order mode propagation 6.2.3 Sound radiation from vibrating structures 6.2.3.1 Physical control mechanisms 6.2.3.2 Control actuators and error sensors. 6.2.4 Active headsets and ear muffs. 6.2.4.1 Feedback systems 6.2.4.2 Feedforward systems 6.2.4.2 Transducer considerations 6.2.4.3 Transducer considerations 6.2.5 Sound transmission into enclosed spaces 6.2.5.1 Global reduction of low frequency tonal noise in propellor aircraft 6.2.5.2 Reduction of interior noise in diesel engine-driven, mobile mining equipment 6.2.5.3 Local reduction of broadband noise in large aircraft 6.2.5.4 Global reduction of low frequency road noise in cars 6.2.6 Active vibration isolation. 6.3 Examples of applications which are impractical. 6.3.1 Global reduction of broadband or high frequency tonal noise in large aircraft 6.3.2 Global reduction of broadband or transient noise transmitted into a building space. 6.3.3 Reduction of traffic or aircraft flyover noise transmitted into a building. 6.3.4 Global reduction of tonal or periodic noise in a large space such as a factory which contains many noise sources. 6.3.5 Global reduction of broadband in a large factory 6.3.6 Reduction of broadband noise outdoors 6.3.7 Reduction of transient noise outdoors. Chapter Seven: Current and Future Directions. 7.1 Commercial control system requirements 7.1.1 Controller hardware 7.1.2 Controller software 7.2 Acoustic system software 7.3 Current research directions 7.3.1 Sound sources 7.3.2 Error sensors 7.3.3 Optimisation of control source and error sensor locations 7.3.4 Control filters and algorithms 7.3.5 Coupled systems 7.3.6 Hybrid active/passive silencers. 7.4 Summary. References. Useful web-sites for more information.