Acoustics Fundamentals, Measurements, and Applications

This four-day course is intended for engineers and other technical personnel and managers who have a work-related need to understand basic acoustics concepts and how to measure and analyze sound. This is an introductory course and participants need not have any prior knowledge of sound or vibration. Each topic is illustrated by relevant applications, in-class demonstrations, and worked-out numerical examples. Since the practical uses of acoustics principles are vast and diverse, participants are encouraged to confer with the instructor (before, during, and after the course) regarding any work-related concerns. Three customized versions of this course are available that emphasize respectively (1. Underwater Acoustics, 2. In-Air Acoustics 3. A broad mix of all acoustic applications tailored to the customer’s need or the majority of class attendees’ interests). On-site courses can be fully customized to the customer’s applications.

• How to make proper sound level measurements.
• How to analyze and report acoustic data.
• The basis of decibels (dB) and the A-weighting scale.
• How intensity probes work and allow near-field sound measurements.
• How to measure radiated sound power and sound transmission loss.
• How to use third-octave bands and narrow-band spectrum analyzers.
• How the source-path-receiver approach is used in noise control engineering.
• How sound builds up in enclosures like vehicle interiors and rooms.

• “Great instructor made the course interesting and informative. Helped clear-up many misconceptions I had about sound and its measurement.”
• “Enjoyed the in-class demonstrations; they help explain the concepts. Instructor helped me with a problem I was having at work, worth the price of the course!”

1. Introductory Concepts. Sound in fluids and solids. Sound as particle vibrations. Waveforms and frequency. Sound energy and power consideration.
2. Acoustic Waves in Air and Water. Plane and spherical acoustic waves. Sound pressure, intensity, and power. Decibel (dB) log power scale. Sound reflection and transmission at surfaces. Sound absorption.
3. Acoustic and Vibration Sensors. Human ear characteristics. Capacitor and piezoelectric microphone and hydrophone designs and response characteristics. Intensity probe design and operational limitations. Accelerometers design and frequency response.
4. Sound Measurements. Sound level meters. Time weighting (fast, slow, linear). Decibel scales (Linear and A-and C-weightings). Octave band analyzers. Narrow band spectrum analyzers. Critical bands of human hearing. Detecting tones in noise. Microphone calibration techniques.
5. Sound Radiation. Human speech mechanism. Loudspeaker design and response characteristics. Directivity patterns of simple and multi-pole sources: monopole, dipole and quadri-pole sources. Acoustic arrays and beamforming. Sound radiation from vibrating machines and structures. Radiation efficiency.
6. Low Frequency Components and Systems. Helmholtz resonator. Sound waves in ducts. Mufflers and their design. Horns and loudspeaker enclosures.
7. Applications. Representative topics include: Outdoor and underwater sound propagation (e.g. refraction due to temperature and other effects). Environmental acoustics (e.g. community noise response and criteria). Auditorium and room acoustics (e.g. reverberation criteria and sound absorption). Structural acoustics (e.g. sound transmission loss through panels). Noise and vibration control (e.g. source-path-receiver model). Topics of interest to the course participants.

Dr. Alan D. Stuart, Associate Professor Emeritus of Acoustics, Penn State, has over forty years of experience in the field of sound and vibration. He has degrees in mechanical engineering, electrical engineering, and engineering acoustics. For over thirty years he has taught courses on the Fundamentals of Acoustics, Structural Acoustics, Applied Acoustics, Noise Control Engineering, and Sonar Engineering on both the graduate and undergraduate levels as well as at government and industrial organizations throughout the country.