AES Warsaw 2015
Paper Session P8
P8 - (Lecture) Transducers—Part 1
Friday, May 8, 14:00 — 16:00 (Room: Królewski)
Chair:
Finn T. Agerkvist, Technical University of Denmark - Kgs. Lyngby, Denmark
P8-1 Assessing Influence of a Headphone Type on Individualized Ear Training—Sungyoung Kim, Rochester Institute of Technology - Rochester, NY, USA; Sean Olive, Harman International - Northridge, CA, USA
Technical ear training has been provided for two groups of engineering students. The treatment group received and conducted the training using a professional-level headphone and the control group did same training with their own consumer-level earphone or headphone. To investigate a possible influence of a headphone type, both groups took two standardized matching tests before and after 15-week technical ear training. The comparison of two test results shows that the headphone type significantly differentiated trainees' matching performance of the treatment group from the control group.
Convention Paper 9272 (Purchase now)
P8-2 GaN Power Stage for Switch Mode Audio Amplification—Rasmus Overgaard Ploug, Technical University of Denmark - Kongens Lyngby, Denmark; Arnold Knott, Technical University of Denmark - Kgs. Lyngby, Denmark; Søren Bang Poulsen, Texas Instruments Denmark A/S - Kongens Lyngby, Denmark
Gallium Nitride (GaN) based power transistors are gaining more and more attention since the introduction of the enhancement mode eGaN Field Effect Transistor (FET), which makes an adaptation from Metal-Oxide Semiconductor (MOSFET) to eGaN based technology less complex than by using depletion mode GaN FETs. This project seeks to investigate the possibilities of using eGaN FETs as the power switching device in a full bridge power stage intended for switch mode audio amplification. A 50 W 1 MHz power stage was built and provided promising audio performance. Future work includes optimization of dead time and investigation of switching frequency versus audio performance.
Convention Paper 9273 (Purchase now)
P8-3 Characterizing the Frequency Response of Headphones—A New Paradigm—Ulrich Horbach, Harman Advanced Technology Group - Northridge, CA, USA
Traditional headphone measurements suffer from large variations if carried out on human subjects with probe microphones, and standardized couplers introduce additional biases, as concluded in a recent paper. Beyond that, there is no clear indication in literature about what the actual perceived frequency response of a headphone might be. This paper explores new measurement methods that avoid the human body as much as possible by measuring the headphone directly, in an attempt to overcome these restrictions and gain more accuracy. Design principles are described in the second part. A novel, DSP controlled, high-quality headphone is introduced that offers the ability to auto-calibrate its frequency response to the individual who is wearing it.
Convention Paper 9274 (Purchase now)
P8-4 Improved Measurement of Leakage Effects for Circum-Aural and Supra-Aural Headphones—Todd Welti, Harman International Inc. - Northridge, CA, USA
Headphone leakage effects can have a profound effect on low frequency performance of headphones. A large survey, including over 2000 individual headphone measurements, was undertaken in order to compare leakage effects on test subjects and leakage effects of the same headphones measured on a test fixture. Ten different commercially available headphones were used, each measured on eight different test subjects and a test fixture with several sets of pinnae. Modifications to the pinnae were investigated to see if the leakage effects measured on the test fixture could be made to better match the real word leakage effects measured on human test subjects.
Convention Paper 9275 (Purchase now)
