Publications
Selected publications currently available in electronic form
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Vitae
- Link to full curriculum vitae, including non-electronic publications.
Refereed Journal Articles
These are formal papers that were invited or accepted for publication in a professional journal based on anonymous peer review of the manuscript.
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[pdf] R.C. Maher, "Lending an ear in the courtroom: forensic acoustics," Acoustics Today, vol. 11, no. 3, pp. 22-29, 2015.
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[pdf] R.C. Maher, "Audio forensic examination: authenticity, enhancement, and interpretation," IEEE Signal Processing Magazine, vol. 26, no. 2, pp. 84-94, 2009.
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[pdf] R.C. Maher, "Control of synthesized vibrato during portamento musical pitch transitions," J. Audio Eng. Soc., vol. 56, no. 1/2, pp. 18-27, 2008.
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[pdf] Z. Chen and R.C. Maher, "Analytical expression for impulse response between two nodes in 2-D rectangular digital waveguide mesh," IEEE Signal Processing Letters, vol. 15, pp. 221-224, 2008.
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[pdf] Z. Chen and R.C. Maher, "Semi-automatic classification of bird vocalizations using spectral peak tracks," J. Acoust. Soc. Am., vol. 120, no. 5, pp. 2974-2984, 2006.
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[pdf] R.C. Maher, "Wavetable synthesis strategies for mobile devices," J. Audio Eng. Soc., vol. 53, no. 3, pp. 205-213, 2005.
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[pdf] P.K. Ramarapu and R.C. Maher, "Methods for reducing audible artifacts in a wavelet-based broad-band denoising system," J. Audio Eng. Soc., vol. 46, no. 3, pp. 178-190, 1998.
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[pdf] S.M. Joseph and R.C. Maher, "Subjective evaluation of four low-complexity audio coding schemes," J. Acoust. Soc. Am., vol. 97., no. 6, pp. 3657-3662, 1995.
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[pdf] R.C. Maher, "A method for extrapolation of missing digital audio data," J. Audio Eng. Soc., vol. 42, no. 5, pp. 350-357, 1994.
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[pdf] R.C. Maher and J.W. Beauchamp, "Fundamental frequency estimation of musical signals using a Two-Way Mismatch procedure," J. Acoust. Soc. Am., vol. 95., no. 4, pp. 2254-2263, 1994.
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[pdf] R.C. Maher, "On the nature of granulation noise in uniform quantization systems," J. Audio Eng. Soc., vol. 40, no. 1/2, pp. 12-20, 1992.
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[pdf] R.C. Maher, "A method for envelope warping in digital audio synthesis," J. Audio Eng. Soc., vol. 39, no. 12, pp. 934-944, 1991.
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[pdf] R.C. Maher, "Evaluation of a method for separating digitized duet signals," J. Audio Eng. Soc., vol. 38, no. 12, pp. 956-979, 1990.
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[pdf] R.C. Maher and J.W. Beauchamp, "An investigation of vocal vibrato for synthesis," Applied Acoustics, vol. 30, no. 2-3, pp. 219-245, 1990.
Refereed Conference Proceedings
These are formal papers that were invited or accepted for presentation at a scholarly conference based on peer review of the entire manuscript.
- [pdf] R.C. Maher, "Examining tell-tale sounds in forensic gunshot recordings," elib 22634, AES 8th International Conference on Audio Forensics, Denver, CO, June 27-29, 2024.
- [pdf] S.B. Nesar, B.M. Whitaker, and R.C. Maher, "A geometric approach for generating synthetic gunshot acoustic signals," elib 22631, AES 8th International Conference on Audio Forensics, Denver, CO, June 27-29, 2024.
- [pdf] S.B. Nesar, B.M. Whitaker, and R.C. Maher, "Machine learning analysis on gunshot recognition," 2024 Intermountain Engineering, Technology and Computing (IETC) Conference, Utah State University, Logan, UT, May 13-14, 2024.
- [pdf] R.C. Maher, "Shot-to-shot variation in gunshot acoustics experiments," elib 20461, Proc. 2019 Audio Engineering Society International Conference on Audio Forensics, Porto, Portugal, June, 2019.
- [pdf] D.R. Begault, S.D. Beck, and R.C. Maher, "Overview of forensic gunshot analysis techniques," elib 20475, Proc. 2019 Audio Engineering Society International Conference on Audio Forensics, Porto, Portugal, June, 2019.
- [pdf] R.C. Maher and T.K. Routh, "Gunshot acoustics: pistol vs. revolver," Proc. 2017 Audio Engineering Society International Conference on Audio Forensics, Arlington, VA, June, 2017.
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[pdf] R.C. Maher and S.R. Shaw, "Gunshot recordings from digital voice recorders," Proc. Audio Engineering Society 54th Conference, Audio Forensics—Techniques, Technologies, and Practice, London, UK, June 2014.
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[pdf][pdf presentation] R.C. Maher and J. Studniarz, “Automatic search and classification of sound sources in long-term surveillance recordings,” Proc. Audio Engineering Society 46th Conference, Audio Forensics—Recording, Recovery, Analysis, and Interpretation, Denver, CO, June 2012.
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[pdf] R.C. Maher and S.R. Shaw, "Directional aspects of forensic gunshot recordings," Proc. Audio Engineering Society 39th Conference, Audio Forensics—Practices and Challenges, Hillerød, Denmark, June 2010.
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[pdf] R.C. Maher, J. Becker, T. Sharpe, J. Peterson, and B.A. Towle, "Development and implementation of a robot-based freshman engineering course," Proc. 2005 American Society for Engineering Education Annual Conference, Portland, OR, June, 2005.
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[pdf] B.J. Gregoire and R.C. Maher, "Harmonic Envelope Detection and Amplitude Estimation Using Map Seeking Circuits," Proc. IEEE International Conference on Electro Information Technology (EIT2005), Lincoln, NE, May, 2005.
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[pdf presentation] R.C. Maher, "Concurrent Audio And Modem Acceleration," Proc. 1999 Windows Hardware Engineering Conference (WinHEC), Los Angeles, CA, March, 1999.
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[pdf] R.C. Maher, "Single-ended spatial enhancement using a cross-coupled lattice equalizer," Proc. 1997 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, Mohonk, NY, October, 1997.
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[pdf] R.C. Maher, "Simple But Useful Tools for Interactive WWW Development," Proc. 1996 Frontiers in Education Conference, Salt Lake City, UT, November, 1996.
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[pdf] Y.J. Chen and R.C. Maher, "Subband coding of audio using a recursively indexed quantizer," Proc. 1995 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, Mohonk, NY, October, 1995.
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[pdf] R.C. Maher, "Computationally efficient compression of audio signals by means of RIQ-DPCM," Proc. 1993 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, Mohonk, NY, October, 1993.
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[pdf] R.C. Maher, "Control of interharmonic beating in polyphonic music," Proc. 1991 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, Mohonk, NY, pp. 1-2, October, 1991.
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[pdf] R.C. Maher, "Development and evaluation of a method for the separation of musical duet signals," Proc. IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, Mohonk, NY, pp. 1-2, October, 1989.
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[pdf] J.W. Beauchamp and R.C. Maher, "Significance of frequency vs. time variations and amplitude beating in additive synthesis of piano tones," Iowa Acoustics Colloquium, Iowa City, IA, p. 1, 1987.
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[pdf] J.W. Beauchamp and R.C. Maher, "Musical acoustics demonstrations, lessons," Proc. IBM Advanced Education Projects Conference, San Diego, CA, 1986.
Formal Professional Conference Proceedings
These are formal papers that were invited or accepted for presentation at a scholarly conference based on peer review of an abstract or extended summary only.
- [pdf] R.C. Maher, "Close and Distant Gunshot Recordings for Audio Forensic Analysis," Express Paper 122, Proc. 155th Audio Engineering Society Convention, New York, NY, October, 2023.
- [pdf] R.C. Maher, "Interpretation of audio forensic information from the shooting of journalist Shireen Abu Akleh," Express Paper 22, Proc. 153rd Audio Engineering Society Convention, New York, NY, October, 2022.
- [pdf] B.F. Miller, F.A. Robertson, and R.C. Maher, "Forensic handling of user generated audio recordings," Preprint 10515, Proc. 151st Audio Engineering Society Convention, Online, October, 2021.
- [pdf] R.C. Maher, "Forensic interpretation and processing of user generated audio recordings," Preprint 10419, Proc. 149th Audio Engineering Society Convention, New York, NY, Online, October, 2020.
- [pdf] E.R. Hoerr and R.C. Maher, "Estimating nonlinear impulse response length using time-delayed mutual information," Preprint 10416, Proc. 149th Audio Engineering Society Convention, New York, NY, Online, October, 2020.
- [pdf] R.C. Maher and E.R. Hoerr, "Forensic comparison of simultaneous recordings of gunshots at a crime scene," Preprint 10281, Proc. 147th Audio Engineering Society Convention, New York, NY, October, 2019.
- [pdf] E.R. Hoerr and R.C. Maher, "Using Volterra series modeling techniques to classify black-box audio effects, " Preprint 10225, Proc. 147th Audio Engineering Society Convention, New York, NY, October, 2019.
- [pdf] R.C. Maher and E.R. Hoerr, "Audio Forensic Gunshot Analysis and Multilateration," Preprint 10100, Proc. 145th Audio Engineering Society Convention, New York, NY, October, 2018.
- [pdf] R.C. Maher, "Challenges of Audio Forensic Evaluation from Personal Recording Devices," Preprint 9897, Proc. 143rd Audio Engineering Society Convention, New York, NY, October, 2017.
- [pdf] R.C. Maher and T.K. Routh, "Wideband audio recordings of gunshots: waveforms and repeatability," Preprint 9634, Proc. 141st Audio Engineering Society Convention, Los Angeles, CA, October, 2016.
- [pdf] T.K. Routh and R.C. Maher, "Determining muzzle blast duration and acoustical energy of quasi-anechoic gunshot recordings," Preprint 9635, Proc. 141st Audio Engineering Society Convention, Los Angeles, CA, October, 2016.
- [pdf] T.K. Routh and R.C. Maher, "Recording anechoic gunshot waveforms of several firearms at 500 kilohertz sampling rate," Proc. Mtgs. Acoust. 26, 030001 (2016); http://dx.doi.org/10.1121/2.0000262, May, 2016.
- [pdf_presentation][lay-language] R.C. Maher, "Gunshot recordings from a criminal incident: who shot first?" J. Acoust. Soc. Am., vol. 139, no. 4, part 2, p. 2024 (abstract), April, 2016.
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[pdf] R.C. Maher and T.K. Routh, "Advancing forensic analysis of gunshot acoustics," Preprint 9471, Proc. 139th Audio Engineering Society Convention, New York, NY, October, 2015.
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[pdf] J. Studniarz and R.C. Maher, "Sound identification from MPEG-encoded audio files," Preprint 8984, Proc. 135th Audio Engineering Society Convention, New York, NY, October, 2013.
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[pdf][pdf_presentation] R.C. Maher, "A method for enhancement of background sounds in forensic audio recordings," Preprint 8731, Proc. 133rd Audio Engineering Society Convention, San Francisco, CA, October, 2012.
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[pptx_presentation][pdf_presentation] R.C. Maher, "Teaching and learning musical acoustics in a music technology program," J. Acoust. Soc. Am., vol. 132, no. 3, part 2, p. 1958 (abstract), October, 2012.
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[pdf] [pdf_presentation] R.C. Maher, "Acoustical modeling of gunshots including directional information and reflections," Preprint 8494, Proc. 131st Audio Engineering Society Convention, New York, NY, October, 2011.
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[pdf_presentation] R.C. Maher and Christine Ford, "Soundscape collaboration for science, management, and public outreach at a national historic site," J. Acoust. Soc. Am., vol. 130, no. 4, part 2, p. 2497 (abstract), 2011.
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[pdf_presentation] R.C. Maher, "Automated analysis and interpretation of long-term soundscape audio recordings," J. Acoust. Soc. Am., vol. 129, no. 4, part 2, p. 2570 (abstract), 2011. .
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[pdf] [pdf presentation] R.C. Maher, "Maintaining sonic texture with time scale compression by a factor of 100 or more," Preprint 8250, Proc. 129th Audio Engineering Society Convention, San Francisco, CA, November, 2010.
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[pdf presentation] R.C. Maher, "Cultural soundscape of the Grant-Kohrs Ranch national historic site," J. Acoust. Soc. Am., vol. 127, no. 3, part 2, p. 1745 (abstract), 2010.
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[pdf] R.C. Maher, "Acoustics of national parks and historic sites: the 8,760 hour MP3 file," Preprint 7893, Proc. 127th Audio Engineering Society Convention, New York, NY, October, 2009.
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[pdf] D. Reed and R.C. Maher, "An investigation of early reflection’s effect on front-back localization in spatial audio," Preprint 7884, Proc. 127th Audio Engineering Society Convention, New York, NY, October, 2009.
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[pdf presentation] R.C. Maher, "Baseline sound monitoring plan for Grant-Kohrs Ranch national historic site," J. Acoust. Soc. Am., vol. 125, no. 4, part 2, p. 2716 (abstract), 2009.
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[pdf] R.C. Maher, "All about phase," Proc. IEEE Signal Processing Society 5th Signal Processing Education Workshop, Marco Island, FL, pp. 218-222, January, 2009.
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[pdf] R.C. Maher and S.R. Shaw, "Deciphering gunshot recordings," Proc. Audio Engineering Society 33rd Conference, Audio Forensics—Theory and Practice, Denver, CO, June 2008.
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[pdf] Z. Chen and R.C. Maher, "Addressing the Discrepancy Between Measured and Modeled Impulse Responses for Small Rooms," Preprint 7239, Proc. 123rd Audio Engineering Society Convention, New York, NY, October, 2007.
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[pdf] Z. Chen and R.C. Maher, "Modeling room impulse response by incorporating speaker polar response into image source method," J. Acoust. Soc. Am. , vol. 121, no. 5, part 2, p. 3174 (abstract), 2007.
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[pdf] [pdf presentation] R.C. Maher, "Acoustical characterization of gunshots," Proc. IEEE SAFE 2007: Workshop on Signal Processing Applications for Public Security and Forensics, Washington, DC, pp. 109-113, April, 2007.
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[pdf] R.C. Maher, "Modeling and signal processing of acoustic gunshot recordings," Proc. IEEE Signal Processing Society 12th DSP Workshop, Jackson Lake, WY, pp. 257-261, September, 2006.
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[pdf] B.J. Gregoire and R.C. Maher, "Map seeking circuits: a novel method of detecting auditory events using iterative template mapping," Proc. IEEE Signal Processing Society 12th DSP Workshop, Jackson Lake, WY, pp. 511-515, September, 2006.
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[pdf] R.C. Maher, "Crossing the bridge: taking audio DSP from the textbook to the DSP design engineer's bench," Proc. IEEE Signal Processing Society 4th Signal Processing Education Workshop, Jackson Lake, WY, pp. 476-481, September, 2006.
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[pdf presentation] S.M. Pascarelle, B. Stewart, T.A. Kelly, A. Smith, and R.C. Maher, "An Acoustic / Radar System for Automated Detection, Localization, and Classification of Birds in the Vicinity of Airfields," 8th Joint Annual Meeting of Bird Strike Committee USA/Canada, St. Louis, MO, August, 2006.
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[pdf] R.C. Maher, J. Gregoire, and Z. Chen, "Acoustical monitoring research for national parks and wilderness areas," Preprint 6609, Proc. 119th Audio Engineering Society Convention, New York, NY, October, 2005.
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[pdf] R.C. Maher, "Audio enhancement using nonlinear time-frequency filtering," Proc. Audio Engineering Society 26th Conference, Audio Forensics in the Digital Age, Denver, CO, July 2005.
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[pdf abstract] [pdf presentation] G. Sanchez, R.C. Maher, and S. Gage, "Ecological and environmental acoustic remote sensor (EcoEARS) application for long-term monitoring and assessment of wildlife," U.S. Department of Defense Threatened, Endangered and at-Risk Species Research Symposium and Workshop, Baltimore, MD, June, 2005.
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[pdf summary] J. Gregoire and R.C. Maher, "Map seeking circuits for audio pattern recognition," Music Information Processing Workshop, Whistler, British Columbia, Canada, December, 2004.
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[pdf] R.C. Maher, "AES Technical Committee on Signal Processing Educational CD Project," Proc. 117th Audio Engineering Society Convention, Preprint 6313, San Francisco, CA, October, 2004.
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[pdf] R.C. Maher, "Compression and Decompression of Wavetable Synthesis Data," Proc. 115th Audio Engineering Society Convention, Preprint #5937, New York NY, October, 2003.
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[pdf] M. Phillips, J. Barish, and R.C. Maher, "The modeling and synthesis of musical signals with PRISM," Proc. 109th Audio Engineering Society Convention, Preprint #5187, Los Angeles, CA, September, 2000.
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[pdf] D.K. Reinhardt and R.C. Maher, "A real time DSP kernel for concurrent audio tasks," Proc. 105th Audio Engineering Society Convention, Preprint #4825, San Francisco, CA, September, 1998.
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[pdf] R.C. Maher, "A low complexity spatial localization system," Proc. 103rd Audio Engineering Society Convention, Preprint #4567, New York, NY, November, 1997.
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[pdf] R.C. Maher, E. Lindemann, and J. Barish, "Old and new techniques for artificial stereophonic image enhancement," Proc. 101stAudio Engineering Society Convention, Preprint #4371, Los Angeles, CA, November, 1996.
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[pdf] R.C. Maher, "Tunable bandpass filters in music synthesis," Proc. 99th Audio Engineering Society Convention, Preprint #4098, New York, NY, October, 1995.
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[pdf] R. Peddibhotla, R.C. Maher and K. Sayood, "A low complexity audio coding scheme for wideband audio," Proc. 1994 Asilomar Conf. on Circuits and Systems, Pacific Grove, CA, vol. 2, pp. 1222-1226, November, 1994.
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[pdf] R.C. Maher, "An efficient scheme for lossy real-time audio data compression," Proc. 1994 Audio Engineering Society Convention, San Francisco, CA, Preprint #3922, pp. 1-13, November 10, 1994.
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[pdf] R.C. Maher and J.L. Varner, "Laboratory development for digital signal processing education," Proc. 1994 ASEE Midwest Section Meeting, Lincoln, NE, pp. 1-4, March 31 - April 2, 1994.
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[pdf] R.C. Maher, "A method for extrapolation of missing digital audio data," Proc. 1993 Audio Engineering Society Convention, New York, NY, Preprint #3715, pp. 1-19, October, 1993.
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[pdf] J.W. Beauchamp, R.C. Maher, and R. Brown, "Detection of musical pitch from recorded solo performances," Proc. 1993 Audio Engineering Society Convention, Berlin, Germany, Preprint #3541, pp. 1-15, March, 1993.
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[pdf abstract][pdf_preprint] D.J. Cheenne, R.D. Kubik, R.C. Maher, and E. Bahar, "Full-wave modeling of the transmission of sound over theater seats: far field investigation," J. Acoust. Soc. Am., vol. 92, no. 4, part 2, p. 2347 (abstract), 1992.
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[pdf abstract] R.C. Maher and J.W. Beauchamp, "Frequency tracking of solo and duet passages using a harmonic two-way mismatch procedure," invited paper, J. Acoust. Soc. Am. , vol. 92, no. 4, part 2, p. 2429 (abstract), 1992.
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[pdf] E.P. Moss and R.C. Maher, 1992, "Synthesis and processing of audible notification and warning signals," Proc. 1992 Audio Engineering Society Convention, San Francisco, CA, Preprint #3354, pp. 1-10, October, 1992.
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[pdf] R.C. Maher, "Sinusoidal additive synthesis revisited," Proc. 1991 Audio Engineering Society Convention, New York, NY, Preprint #3128, pp. 1-19, October, 1991.
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[pdf abstract][pdf_preprint] R.C. Maher, "Computer processing of audio signals by exclusion filters," J. Acoust. Soc. Am. Suppl. 1, vol. 88, p. 188 (abstract), 1990.
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[pdf abstract] J.W. Beauchamp and R.C. Maher, "Partial synchrony in musical sounds: some recent results using time-variant spectral analysis," invited paper, J. Acoust. Soc. Am. Suppl. 1, vol. 84, pp. 103-104 (abstract), 1988.
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[pdf abstract] R.C. Maher and J.W. Beauchamp, "Is there a single vibrato waveform?" J. Acoust. Soc. Am. Suppl. 1, vol. 83, p. 31 (abstract), 1988.
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[pdf abstract][pdf_report1][pdf_report2] R.C. Maher and J.W. Beauchamp, "A microcomputer-based demonstration system for acoustics education" J. Acoust Soc. Am. Suppl. 1, vol. 81, p. 32 (abstract), 1987.
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[pdf abstract] R.C. Maher, J.H. Scandrett, R.E. Crawford, Jr., and K. Grant, "A low-cost digital synthesizer system for music applications and psychoacoustical research," J. Acoust Soc. Am. Suppl. 1, vol. 77, p. 75 (abstract), 1985.
United States Patents
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[pdf] D. Kosek and R.C. Maher, "Audio Spectral Noise Reduction Method and Apparatus," Patent Number 7,742,914, June 22, 2010.
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[pdf] R.C. Maher and J. Barish, "Scalable Audio Processing on a Heterogeneous Processor Array," Patent Number 6,301,603, October 9, 2001.
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[pdf] R.C. Maher, "Audio Spatial Enhancement Apparatus and Methods," Patent Number 6,111,958, August 29, 2000.
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[pdf] R.C. Maher, "Audio Spatial Localization Apparatus and Methods," Patent Number 6,078,669, June 20, 2000.
White Papers and Research Monographs
These are formal articles that were prepared in response to a specific funding solicitation, a required progress report, or a specific query by a research sponsor.
- [pdf] R.C. Maher, "How to be a great peer reviewer for the AES Journal," Invited seminar presentation, 153rd Audio Engineering Society Convention, New York, NY, October, 2022.
- [pdf] R.C. Maher, “Advancing Audio Forensics of Gunshot Acoustics,” Final Summary Overview, National Institute of Justice Award number: 2014-DN-BX-K034, April 2018.
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[pdf] R.C. Maher, "Final Report: Baseline Sound Monitoring at Grant Kohrs Ranch National Historic Site," project report prepared for Grant Kohrs Ranch NHS, Deer Lodge, MT, 181 pages, September 7, 2012.
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[pdf] R.C. Maher, "Summary of Gunshot Acoustics," white paper prepared for Advanced Acoustic Concepts, Inc., Hauppauge, NY, 7 pages, April 4, 2006.
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[pdf] Z. Chen and R.C. Maher, "Parabolic Dish Microphone Principles and Characteristics," progress report prepared for Advanced Acoustic Concepts, Inc., Hauppauge, NY, 10 pages, August 12, 2005.
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[pdf] Z. Chen and R.C. Maher, "Atmospheric Sound Propagation Considerations for the Birdstrike Project," progress report prepared for Advanced Acoustic Concepts, Inc., Hauppauge, NY, 10 pages, July 28, 2004.
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[pdf] R.C. Maher, "Obtaining Long-Term Soundscape Inventories in the U.S. National Park System," white paper prepared for National Park Service Natural Sounds Program Office, Fort Collins, CO, 12 pages, January 30, 2004.
Academic Papers
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[pdf] "Development of a Software-Based Real-Time Digital Synthesizer," M.S. Report, Electrical Engineering, University of Wisconsin, Madison, Wisconsin, 1985.
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[pdf] "An Approach for the Separation of Voices in Composite Musical Signals," Ph.D. Dissertation, Electrical Engineering, University of Illinois, Urbana, Illinois, 1989. Dissertation Advisor: Dr. James W. Beauchamp.
Other Publications
Miscellaneous articles and reprints.
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[pdf] R.C. Maher, "PC audio subsystems: evolution and design," Electronic Engineering Times, Issue 1540, pp. 36-40, September, 2008.
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