Review of literature
Stethoscope Design
Abenson, Denis. "A high-fidelity electronic stethoscope." JAMA 218.5 (1971): 741-741. http://jama.jamanetwork.com/article.aspx?articleid=339694
Dowell, Larry A., GEORGE E. FANT, and DAVID W. WATKINS. "Technical Note: Design and Construction of an Electronic Stethoscope." Journal of clinical engineering 13.5 (1988): 355-358. http://journals.lww.com/jcejournal/Abstract/1988/09000/Technical_Note__Design_and_Construction_of_an.9.aspx
Ertel, Paul Y., et al. "Stethoscope acoustics II. Transmission and filtration patterns." Circulation 34.5 (1966): 899-909. http://circ.ahajournals.org/content/34/5/899.short
Grenier, M. C., et al. "Clinical comparison of acoustic and electronic stethoscopes and design of a new electronic stethoscope." The American journal of cardiology 81.5 (1998): 653. http://www.ajconline.org/article/S0002-9149%2897%2900977-6/abstract
Hahn, A. W. "On stethoscope design: a challenge for biomedical circuit designers." Biomedical sciences instrumentation 37 (2000): 499-503. http://europepmc.org/abstract/MED/11347442
Hampton, C. S., and A. Chaloner. "Which stethoscope?." British medical journal 4.5576 (1967): 388. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1748695/
Kadam Patil, D. D., and R. K. Shastri. "Design of wireless electronic stethoscope based on zigbee." arXiv preprint arXiv:1202.1680 (2012). http://arxiv.org/ftp/arxiv/papers/1202/1202.1680.pdf
Littmann, David. "An Approach to the Ideal Stethoscope." J.A.M.A., 178 (5), 504-505.
Mangion, Kenneth. "The stethoscope." Malta Medical Journal 19.02 (2007): 4. http://www.um.edu.mt/umms/mmj/PDF/178.pdf
McMechan, Christian, and Poman So. "Design and implementation of a low cost electronic stethoscope." Communications, Computers and Signal Processing (PacRim), 2011 IEEE Pacific Rim Conference on. IEEE, 2011. http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6032981&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6032981
Rappaport, Maurice & Sprague, Howard. Physiologic and Physical Laws that Govern Auscultation, And Their Clinical Application. 1941. The American Heart Journal, 21 (3), 257- 318.
Secrest, Rose. "Stethoscope." How Products Are Made. 1994. Encyclopedia.com. 30 Dec. 2014 http://www.encyclopedia.com/topic/stethoscope.aspx
Singh, Kuldeep & Abrol, Preeti. "Design and Development of a Digital Stethoscope for Cardiac Murmur." 2013. International Journal of Computer Applications, 73(33), 20-22.
Zhang, Honghai, et al. "Design of a flexible stethoscope sensor skin based on MEMS technology." Electronic Packaging Technology, 2006. ICEPT'06. 7th International Conference on. IEEE, 2006. http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=4198956&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D4198956
Stethoscope Testing
Abella, Manuel, Penney, David & Formolo John. "Comparison of the Acoustic Properties of Six Popular Stethoscopes". 1992. The Journal of the Acoustic Society of America, 91(4), 2224- 2228.
Ertel, Paul Y., et al. "Stethoscope acoustics I. The Doctor and His Stethoscope." Circulation 34.5 (1966): 889-898.
Fontaine, Emmanuelle et al. "In-Flight Auscultation During Medical Air Evacuation: Comparison Between Traditional and Amplified Stethoscopes." 2014. Air Medical Journal Associates, 283-285.
Groom, D, Charleston, S. "Comparative efficiency of stethoscopes." Department of Medicine, Medical College of South Carolina, 1963. http://www.ncbi.nlm.nih.gov/pubmed/14204317
Hampton, C. S., and A. Chaloner. "Which stethoscope?." British medical journal 4.5576 (1967): 388. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1748695/ (NOTE: this is already cited above under Design as well.)
Iverson, K, et al. "Effect of teaching and type of stethoscope on cardiac auscultatory performance." Clinic of Cardiology, 2006. http://www.ncbi.nlm.nih.gov/pubmed/16824835
Johnston, Franklin & Kline, Edward. "An Acoustical Study of the Stethoscope.' 1938. University Hospital Bulletin, Ann Arbor, 128(4), 328- 339.
Kindig, J, Beeson, T, Campbell, R, Andries, F, and Tavel, M. "Acoustical performance of the stethoscope: A comparative analysis" Curriculum in Cardiology, 1981. http://www.ncbi.nlm.nih.gov/pubmed/7102511
Korhonen, Pekka, et al. "Frequency Response Measurements on Commercially Available Stethoscopes" Medical & Biological Engineering & Computing, 1996. http://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CB4QFjAA&url=http%3A%2F%2Fwww.isbem.org%2Fconf%2F1996%2F1996nbc%2F1-1-6-07.pdf&ei=cD8PVZTlIsLvgwSgqIPYBw&usg=AFQjCNGHbJhDF9I2A2qA9zKEM74u62Cysg&bvm=bv.88528373,d.eXY
Kraman, S, Pressler, G, Pasterkamp, H, and Wodicka, G. "Design, Construction and Evaluation of a BioAcoustic Transducer Testing (BATT) System for Respiratory Sounds." IEEE Transactions on Biomedical Engineering, 53(8), 2006. http://www.ncbi.nlm.nih.gov/pubmed/16916109
Lok, Charmaine, Morgan, Christopher, and Ranganathan, Narasimhan. " The Accuracy and Interobserver Agreement in Detecting the 'Gallop Sounds by Cardiac Ausculation" Chest, 1998. http://www.ncbi.nlm.nih.gov/pubmed/9824002
Rappaport, Maurice & Sprague, Howard. " The Effects of Tubing Bore on Stethoscope Efficiency." 1951. American Heart Journal, 605-609.
"Stethoscopes: what are we hearing?" http://www.ncbi.nlm.nih.gov/pubmed/17849763
http://www.google.ca/patents/US7289634
State of the device
Welsby, P. & Earis, J. " Some high pitched thoughts on chest examination." 2001. Postgraduate Medical Journal, 77, 617-620.