Charles King, Acoustical Engineering and Analysis

Charles Bender King

ACOUSTICAL ENGINEER

Analyzed, designed and evaluated a wide variety of transducers and acoustical systems from traditionally designed devices to emerging transducer technology. Worked on compression drivers, direct radiators, horns and mechanical sirens as stand-alone devices, as well as part of an array or system.

Utilized ANSYS Multi-Physics, Mathematica, Maple, PSpice, ProE and Labview to design new products and improving existing speaker lines.
Created patentable solutions to performance issues in receivers, phaseplugs and waveguides.
Investigated and validated designs using a variety of custom and off-the-shelf acoustical measurement tools.

ANALYSIS EXPERIENCE

Extensive use of ANSYS Multi-Physics Finite Element Analysis software, including the Acoustical, Electro-Magnetic, and Mechanical packages. Wrote extensive scripting within the framework of ANSYS Parametric Design Language. Obtained simulation accuracy better than 5% for magnetic analysis and within 2 dB for directivity analysis.
Developed and prioritized technical design criteria in terms of directivity, efficiency, power handling and reliability from an evaluation of application requirements of the Outdoor Warning, Industrial Signaling and Vehicular Warning markets.
Created equivalent electrical circuit models of transducers in PSpice to perform initial evaluation of driver efficiency, impedance, and the sensitivity of the overall performance against changes in specific design variables.
Used advanced analysis techniques to evaluate details of motor structures, horns, diaphragms, formers and lead wires. Generated, evaluated, and optimized models within ANSYS. Utilized Maple for post-processing and data visualization.

TEST AND MEASUREMENT EXPERIENCE

Utilized Anechoic Chambers, Plane Wave Tubes, and Reverberation Chambers with a variety of measurement tools, including specialized audio tools made by Breul and Kjaer, GRAS, Agilent, the MLSSA acoustical measurement system, and general measurement tools such as spectrum analyzers, power analyzers, and oscilloscopes.
Developed customized methods of testing and evaluating product performance within the laboratory. Utilized AES, ANSI, SAE and ISO recommended practices and standards when available. Moved Labs towards ISO 17025 compliance.
Implemented full-power swept-square wave testing of acoustical devices and statistical analysis of inventory lots of loudspeakers.
Trained engineers and technicians from multiple engineering organizations in complex noise, vibration and instrumentation projects.
Represented Federal Signal in the development of industry standards with Underwriters Laboratory (UL1480, Speakers for Fire Alarm, Emergency, and Professional Use) and the Society of Automotive Engineers (SAE J1849, Measurement of Emergency Vehicle Sirens).

WORK HISTORY

Research and Development, Knowles Electronics, Itasca IL

Principle Engineer / Scientist, 2006-Present
Senior Acoustical Test Engineer, 2002

Technology Group, Federal Signal Corporation (1,2,3),Tinley Park, IL

Acoustical Analyst, 1999

Research and Development, Federal Signal Corporation, UniversityPark, IL

Audio Design Engineer II, 1999
Audio Design Engineer, 1996
Design Engineer, 1995

Sound Engineer, Consultant, Various locations, 12/86- Present

Chief Engineer, KCPR, San Luis Obispo, CA, 4/94- 8/95

Lab Aide, City College of San Francisco, San Francisco, CA, 9/92 - 6/93

Service Representative, Wells Fargo Bank / RKB Personnel, San Francisco, CA, 10/89 - 11/91

Supervisor, Burke Marketing Research, Dayton,OH, 6/87 - 5/89