Dan Mennitt

Daniel J. Mennitt, Ph.D.

Senior Associate
Mechanical Engineering
Denver

Dr. Mennitt specializes in acoustics and has expertise in the characterization, design, and modeling of acoustical environments and devices. He has over 15 years of experience in acoustics, environmental noise, and noise control and is a certified Occupational Hearing Conservationist. He has worked extensively with federal agencies to assess environmental noise and the consequences of noise exposure to humans and ecological systems. Dr. Mennitt also has considerable experience in signal processing and has developed algorithms for applications such as detection, localization, filtering, feature extraction, and optimization. He has applied his expertise to the analysis of both free field and diffracting microphone arrays in terrestrial and underwater environments. Dr. Mennitt’s research background also involves predictive modeling and the statistical analysis of large datasets.

Prior to joining Exponent, Dr. Mennitt worked in partnership with Colorado State University and the National Park Service’s Natural Sounds and Night Skies Division to manage acoustical environments. His research involved the spatiotemporal patterns of environmental sound on landscape scales, impacts of noise exposure, acoustical transducers, bioacoustics, and predictive modeling. Dr. Mennitt has designed devices for calibration and monitoring sound in extremely quiet environments with empirical, analytical and numerical methods. Measurements in quiet environments are especially prone to contamination and his research utilized signal processing and machine learning techniques for noise reduction and robust data acquisition. He has also directed large environmental noise studies in urban areas.

Dr. Mennitt has a strong background in scientific programming and experience with statistical learning, data mining, and time and frequency domain simulations of acoustic propagation. He led a multidisciplinary team to pioneer a framework for geospatial sound modeling that allows for comprehensive mapping of environmental sound levels on national scales. He has worked with academia, government, and industry to translate these estimates of noise exposure to implications for land management, ecological, epidemiological, military, and commercial applications. Related research in underwater acoustics demonstrated the utility of passive acoustical monitoring and environmental data to predict trends in marine biodiversity. While at Colorado State University, Dr. Mennitt also lectured on acoustics, noise, and signal processing.

Dr. Mennitt’s background is in mechanical engineering. He performed his doctoral work at Virginia Tech’s Vibration and Acoustics Laboratory, investigating localization and tracking of acoustic sources in free-field and cluttered environments. During this research, he developed robust statistical methods for classification of acoustical signals and fusion of information from distributed sensor networks. He has also created tools for beamforming, adaptive filtering, and speech applications with diffracting microphone arrays. While at the Vibration and Acoustics Laboratory, he assisted with laboratory measurements and testing with anechoic and reverberation rooms, intensity probes, impedance tubes, modal impact hammers, accelerometers, and shakers. Additional graduate work included studies in virtual acoustic prototyping, architectural acoustics, and audio engineering. His training and expertise in audio engineering helps Dr. Mennitt conduct educated and critical observations to address acoustical issues.

CREDENTIALS & PROFESSIONAL HONORS

  • Ph.D., Mechanical Engineering, Virginia Polytechnic Institute and State University, 2008, magna cum laude
  • B.S., Mechanical Engineering, Virginia Polytechnic Institute and State University, 2004, magna cum laude
  • The Robert Bradford Newman Medal for Merit in Architectural Acoustics, 2005

LICENSES & CERTIFICATIONS

Occupational Hearing Conservationist (OHC), Council for Accreditation in Occupational Hearing Conservation, 503540

Publications

D. J. Mennitt, “An adaptive coupler for the calibration of the arbitrarily shaped microphones,” Applied Acoustics 154 (2019):114-120.

D. J. Mennitt, K. Fristrup, and B. Notaros, “Characterization of gain and directivity of exponential horn receivers,” The Journal of the Acoustical Society of America, 142 (2017):3257-3266.

C. D. Francis, D. Taff, P. Newman, C. White, C. A. Monz, M. Levenhagen, A. R. Petrelli, L. C. Abbott, J. Newton, S. Burson, C. B. Cooper, Kurt M. Fristrup, C. McClure, D. J. Mennitt, M. Giamellaro, J. R. Barber, “Acoustic Environments Matter: Synergistic benefits to humans and ecological communities,” Journal of Environmental Management, 203 (2017):245-254.

J. A. Casey, R. Morello-Frosch, D. J. Mennitt, K. M. Fristrup, E. L. Ogburn, and P. James, “Inequity in noise pollution in the United States,” Environmental Health Perspectives, 77017 (2017):1-10.

R. T. Buxton, M. F. McKenna, D. J. Mennitt, K. M. Fristrup, K. Crooks, L. Angeloni, and G. Wittemyer, “Noise pollution is pervasive in US protected areas.” Science 356, no. 6337 (2017):531-533.

D. J. Mennitt and K. Fristrup, “Influential factors and spatiotemporal patterns of environmental sound levels in the contiguous United States,” Noise Control Engineering Journal, 64 (2016):342-353.

D. J. Mennitt, K. Fristrup, and K. Sherrill, “A geospatial model of ambient sound pressure levels in the contiguous United States,” The Journal of the Acoustical Society of America 135 (2014):2746-2764.

D. J. Mennitt, K.M. Fristrup, “Obtaining calibrated sound pressure levels from consumer digital audio recorders,” Applied Acoustics 73 (2012):1138-1145.

K. M. Fristrup, and D. J. Mennitt. “Bioacoustical monitoring in terrestrial environments.” Acoustics Today 8:16-24 (2012).

D. J. Mennitt, and M. Johnson, “Multiple-array passive acoustic source localization in urban environments,” The Journal of the Acoustical Society of America, 127.5 (2010): 2932-2942.

M. Ermann, M. R. F. Kidner, and D. J. Mennitt, “Mapping the sound field of a 400 seat theater,” Building Acoustics 13.3 (2006):199-210.

Conference Proceedings

D. J. Mennitt, M. F. McKenna, and K. M. Fristrup, “Continental perspectives of noise exposure and its effects,” INTER-NOISE and NOISE-CON Congress and Conference Proceedings, 255 (2017):1168-1172.

D. J. Mennitt and K. Fristrup, “Influential factors and spatiotemporal patterns of environmental sound levels,” INTER-NOISE and NOISE-CON Congress and Conference Proceedings, 250 (2015):2029-2040.

D. J. Mennitt, K. Fristrup, K. Sherrill, and L. Nelson, “Mapping sound pressure levels on continental scales using a geospatial sound model,” INTER-NOISE and NOISE-CON Congress and Conference Proceedings, 1 (2013):1-11.

D. J. Mennitt, P. Gillett, J. Carneal and M. Johnson, “Tracking Noise Sources Using Multiple Mobile Microphone Arrays,” Thirteenth International Congress on Sound and Vibration, Vienna, Austria (2006):1-8.

Technical reports

D. J. Mennitt and B. J. Ikelheimer, “Geospatial sound modeling for military and community noise metrics,” Prepared for the United States Army (2017).

Presentations

D.J. Mennitt, D. Joyce, and K. Fristrup, “Benefits and challenges of using consumer audio equipment for unattended acoustical monitoring,” The Journal of the Acoustical Society of America, 144, 1828 (2018).

J. A. Casey, A. Shev, D. Paksarian, K. R. Merikangas, D. J. Mennitt, and K. E. Rudolph, “Association between exposure to noise and sleep and mental health outcomes in a nationally-representative sample of U.S. adolescents,” 2018 Annual Conference of the International Society for Environmental Epidemiology (2018).

K. Fristrup, M.F. McKenna, and D.J. Mennitt, “Forecasting increases in recreational value that would result from restoration of natural soundscapes in National Parks,” The Journal of the Acoustical Society of America, 143, 1806 (2018).

M. F. McKenna, D. J. Mennitt, M. Thompson, J. Stanley, S. Van Parijs, K. M. Fristrup, and L. Hatch, “Including acoustical features in marine ecological prediction,” NOAA-Navy Workshop: Soundscape Metrics to Support Marine Protected Area Management, Woods Hole Oceanographic Institution, MA (2018).

D. J. Mennitt, “Classification of wind induced pseudo noise using low resolution features,” National Park Service, Natural Resource Stewardship and Science, Fort Collins, CO (2017).

D. J. Mennitt, Megan F. McKenna, and Kurt M. Fristrup, “Continental perspectives of noise exposure and its effects,” INTER-NOISE and NOISE-CON Congress and Conference Proceedings, 255 (2017):1168-1172.

D. J. Mennitt and K. Fristrup, “Gain and directivity of exponential horn receivers,” The Journal of the Acoustical Society of America 140, 3140 (2016).

D.J. Mennitt and K. Fristrup, “Anomaly detection and other practical considerations for estimating acoustical metrics from time series data,” The Journal of the Acoustical Society of America, 140, 3424 (2016).

D. J. Mennitt and K. M. Fristrup, “A geospatial approach to mapping environmental sound levels across the United States,” American Society for Photogrammetry and Remote Sensing, Geobytes (2016).

J. A. Casey, R. Morello-Frosch, D. J. Mennitt, K. M. Fristrup, and P. James, "The distribution of noise pollution along racial and socioeconomic lines in the United States," 28th Annual Conference of the International Society of Environmental Epidemiology, Rome, Italy (2016).

P. James, R. Banay, D. J. Mennitt, K. Fristrup, J. Africa, J. Hart, F. Laden, "Noise and Cardiovascular Disease in a Nationwide Cohort Study," 28th Annual Conference of the International Society of Environmental Epidemiology, Rome, Italy (2016).

R. T. Buxton, M. McKenna, E. Brown, D. J. Mennitt, K. Fristrup, K. Crooks, L. Angeloni, G. Wittemyer, “Noise Exposure in U. S. Protected Areas,” American Association for the Advancement of Science, Washington DC (2016).

D. J. Mennitt, L. Hatch, K. M. Fristrup, M. Thompson, D. Cholewiak, M. F. McKenna, P. Auster and S. Van Parijs, “A geospatial approach to exploring the soundscape of Stellwagen Bank National Marine Sanctuary,” Oceanoise 2015, Vilanova i la Geltrú, Spain (2015).

D. J. Mennitt, E. Brown, and K.M. Fristrup, “Assessing the condition of acoustical resources across the National Park Service Units,” 2015 George Wright Society Conference on Parks, Protected Areas, and Cultural Sites, Oakland, CA (2015).

M. F. McKenna, K. M. Fristrup, and D. J. Mennitt, “Predicting historic and current sound levels from point measurements: a geospatial model,” Science for Parks, Parks for Science: The Next Century, Berkeley, CA (2015).

K. Fristrup, D. Joyce, E. Lynch, M. Mckenna, D. J. Mennitt, “Monitoring and modeling sound levels at landscape scales in U. S. National Parks,” Ecology and acoustics: emergent properties from community to landscape, Paris, France (2014).

D. Risch, P. Auster, D. Cholewiak, K. Fristrup, L. Hatch, M. McKenna, D. Mennitt, M. Thompson, and S. Van Parijs, “Monitoring bio-acoustic activity & geospatial models of ambient sound: Applications in a marine sanctuary,” Ecology and acoustics: emergent properties from community to landscape, Paris, France (2014).

C. Walker, S. Buxner, D. J. Mennitt, C. Cooper, S. O’Connor, and S. M. Pompea, “Using NGSS to Shape Research Projects with Citizen-Science Data,” Astronomical Society of the Pacific Annual Meeting, Burlingame, California (2014).

D. J. Mennitt, K. Fristrup, and K. Sherrill, “A geospatial model of ambient sound pressure levels in the continental United States,” The Journal of the Acoustical Society of America 132, 1926 (2012).

D. J. Mennitt, "Spatial variation of natural ambient sound pressure levels in Rocky Mountain National Park." The Journal of the Acoustical Society of America 129, 2617 (2011). M. Ermann, J. Carneal, D. Mennitt, C. Jackson, B. Karmarkar, M. Helveston, and P. Clay, “Sound transmission loss of nontraditional building materials and redundancies,” The Journal of the Acoustical Society of America 122(5) (2007).

D. J. Mennitt, M. Johnson, and J. Carneal, “Coarse classification of acoustic signals using temporal and spectral characteristics,” Journal of the Acoustical Society of America 121(5):3046 (2007).

J. Carneal, M. Johnson, D. J. Mennitt, and P. Gillett, “Localization and tracking noise sources with autonomous vehicles: from node processing to central command fusion and tracking,” Acoustical Society of America's North Carolina Chapter, Raleigh, NC (2006).

D. J. Mennitt, “Numerical accuracy of virtual acoustic prototyping: determination of the minimum size of the evaluation sphere to achieve accurate local simulation,” Acoustical Society of America's North Carolina Chapter, Raleigh, NC (2006).

D. J. Mennitt, J. Redenshek, A. Tawney “Acoustical mapping of the lyric theater,” Acoustical Society of America's North Carolina Chapter, Blacksburg, VA (2005).

Academic Appointments

Research Scientist III, Department of Electrical and Computer Engineering, Colorado State University, 2018-2019

Research Scientist II, Department of Electrical and Computer Engineering, Colorado State University, 2015-2018

Research Scientist I, Department of Electrical and Computer Engineering, Colorado State University, 2010-2015

Graduate Research Assistant, Department of Mechanical Engineering, Virginia Polytechnic Institute and State University, 2004-2008

Professional Affiliations

Acoustical Society of America

Institute of Noise Control Engineering

Additional Information

Peer Reviewer

Noise Control Engineering Journal

Journal of the Acoustical Society of America

Environment International Journal

CREDENTIALS & PROFESSIONAL HONORS

  • Ph.D., Mechanical Engineering, Virginia Polytechnic Institute and State University, 2008, magna cum laude
  • B.S., Mechanical Engineering, Virginia Polytechnic Institute and State University, 2004, magna cum laude
  • The Robert Bradford Newman Medal for Merit in Architectural Acoustics, 2005

LICENSES & CERTIFICATIONS

Occupational Hearing Conservationist (OHC), Council for Accreditation in Occupational Hearing Conservation, 503540