AES Berlin 2014
Engineering Brief EB3
EB3 - Poster Session 2
Tuesday, April 29, 10:00 — 11:30 (Foyer)
EB3-1 An Approach to Bass Enhancement in Portable Computers Employing Smart Virtual Bass Synthesis Algorithms—Piotr Hoffmann, Gdansk University of Technology - Gdansk, Poland; Tomasz Sanner, Gdansk University of Technology - Gdansk, Poland; Bozena Kostek, Gdansk University of Technology - Gdansk, Poland; Audio Acoustics Lab.
The aim of this paper is to present a novel approach to the Virtual Bass Synthesis (VBS) algorithms applied to portable computers. The developed algorithms are related to intelligent, rule-based setting of synthesis parameters according to music genre of an audio excerpt and to the type of a portable device in use. To find optimum synthesis parameters of the VBS algorithms, subjective listening tests based on a parametric procedure were performed. The classification of music genres is automatically executed employing MPEG 7 parameters and the Principal Component Analysis method applied to reduce information redundancy. The VBS algorithm performs the synthesis based on a nonlinear device (NLD) or phase vocoder (PV) depending on the content of an audio file excerpt. A soft computing (fuzzy logic) algorithm is employed to set optimum synthesis parameters depending on a given song.
Engineering Brief 144 (Download now)
EB3-2 Energy Based Traffic Density Estimation Using Embedded Audio Processing Unit—György Nagy, Fraunhofer Institute for Digital Media Technology IDMT - Ilmenau, Germany; Rene Rodigast, Fraunhofer Institute for Digital Media Technology IDMT - Ilmenau, Germany; Danilo Hollosi, Fraunhofer Institute for Digital Media Technology IDMT - Ilmenau, Germany
In this paper we present preliminary results of an audio-based traffic density estimation application, developed within the EU-FP7 project EAR-IT [1]. The algorithm exploits that the energy of environmental noise, generated by vehicles, is related to the prevalent traffic conditions. Noise analysis and derived restrictions were made to improve the solution, which was implemented on an embedded platform. This approach follows the current trends—distributed and local processing—and directly targets the requirements for smart cities and wireless sensor networks.
Using traffic monitoring wireless sensors, provided by the testbed SmartSantander [2], development setup was established to support the audio related algorithm deployment, testing, and assessment.
Engineering Brief 145 (Download now)
EB3-3 Objective Evaluation Method for the Perceived Quality of Car Horns—Taejin Shin, Inha University - Inchon, Korea; Sang-Kwon Lee, Inha University - Inchon, Korea
This paper presents an objective evaluation method for the perceived quality of car horn sound based on a psychoacoustic metric and a subjective test. A new psychoacoustic metric called the “spectrum decay (SD) slope” was developed to evaluate a luxury timbre in the sound quality of the horn sound. Eight synthetic sounds with a variety of SDS slope are designed. The synthetic sounds are subjectively evaluated by 41 subjects. A sound quality index for car horn sound is developed based on the correlation between the SD slope and subjective rating for synthetic sounds. The sound quality index is applied to the estimation of the sound quality of horn sounds of ten passenger cars measured inside the cars. The measured horn sounds are also evaluated subjectively by the same 41 subjects. The correlation between the estimated subjective rating and the subjective rating evaluated by the subjects is sufficient (R= 0.93, p <0.01) for the validation of the sound quality index.
Engineering Brief 146 (Download now)
EB3-4 Fitting the Mobile Device Characteristics to the User's Hearing Preferences—Kuba Lopatka, Gdansk University of Technology - Gdansk, Poland; Piotr Suchomski, Gdansk University of Technology - Gdansk, Poland; Andrzej Ciarkowski, Gdansk University of Technology - Gdansk, Poland; Piotr Odya, Gdansk University of Technology - Gdansk, Poland; Andrzej Czyzewski, Gdansk University of Technology - Gdansk, Poland
A method for fitting the mobile computer audio characteristics to the user's hearing preferences is proposed. The process consists of two stages: calibration and dynamics processing. During the calibration phase the user performs a loudness scaling test giving their response regarding the perceived loudness. The dynamics processing made on above basis sets the loudness to the most comfortable level. The processing accounts both for the user's hearing preferences (or possible deficiencies) and for the playback characteristics of the device. The solution is implemented as a standalone PC calibration application and as an APO object installed in the system's audio driver.
Engineering Brief 147 (Download now)
EB3-5 Recreating Robb: The Sound of the World’s First Electronic Organ—Michael Murphy, Ryerson University - Toronto, ON, Canada; Max Cotter, Ryerson University - Toronto, Ontario, Canada
This paper follows up from a 2013 AES presentation reporting on the recreation of the sound of the Robb Wave Organ, the first successful electronic organ, prototyped in 1927. The organ employed primitive “PCM-like” sampling techniques in its tone wheel construction. Our work has led to the compilation of recordings of the last known organ into a MIDI-operable cross-platform sample library for public use, bringing the instrument back to life and out of obscurity. The presentation will feature playable sample sets as well as audio comparisons between the Wave organ and the pipe organs it attempted to reproduce. Audiences will be encouraged to interact with the instrument while gaining a sense of its history and contribution to early sample-based synthesis.
Engineering Brief 148 (Download now)
EB3-6 Reproduction of the Radiation Pattern from a Practical Source by an Acoustic Array and the Equivalent Source Method—Wan-Ho Cho, Korea Research Institute of Standards & Science - Yuseonggu, Daejeon, Korea
Complicated radiated patterns and strengths from actual source can be approximately described by the expansion of spherical harmonics or, in other words, ideal sources, in various orders. If the signals are superposed to meet the requirement for generating a specially designed radiation pattern of ideal sources in various orders, an arbitrary radiation pattern simulating the actual source of interest can be reproduced by this designed filter. The method based on the equivalent source method is proposed to design a source array to reproduce not only frequency response but also the spatial response to simulate the sound field, and the suggested method is applied to reproduce the radiation pattern of musical instruments with spherically distributed loudspeaker array.
Engineering Brief 149 (Download now)
