AES Warsaw 2015
Engineering Brief EB-1
EB-1 - e-Brief Posters
Saturday, May 9, 16:00 — 18:00 (Foyer)
EB-1-1 Preferred Sound Level for Concert Listeners and Correlations between Sound Quality Dimensions—Avo-Rein Tereping, Tallinn University, Institute of Psychology - Tallinn, Estonia
Increasing loudness at concert performances is not caused by listeners’ preferences, but by the opinions of sound engineers and/or producers. The average sound level at public concerts ranges up to 100–105 decibels. Loudness preferences have been examined for listening with earphones but not in the open air. This e-brief describes research on preferred sound quality dimensions at Nordea Concert Hall in Tallinn with live music samples. The experiments revealed that preferred loudness don’t differ across age groups or between women and men. The preferred loudness were found 85–87 dB. Fidelity was the most important sound quality parameter influencing to overall pleasantness. No correlation were found between loudness and overall pleasantness.
Engineering Brief 183 (Download now)
EB-1-2 Evaluation of a Novel Approach to Virtual Bass Synthesis Strategy—Piotr Hoffmann, 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) strategy applied to portable computers. The developed algorithms involve intelligent, rule-based settings of bass synthesis parameters with regard to music genre of an audio excerpt and the type of a portable device in use. The Smart VBS algorithm performs the synthesis based on a nonlinear device (NLD) with artificial controlling synthesis system according to music genre. Classification of musical genres is performed using the k-Nearest Neighbor algorithm and the extracted MPEG 7-based feature vectors optimized by the Principal Component Analysis method. To confirm the relationship between the presented excerpt of music from a variety of music genres and the listener’s preferences, subjective tests using the Mushra method are performed. On the basis of the listeners’ opinions statistical tests are carried out and show that listeners in most cases prefer the SVBS strategy developed by the authors in comparison to either an audio excerpt with the bass boost algorithm applied and unprocessed audio file. Furthermore, the listeners indicated that perception of the proposed SVBS strategy is similar for different types of portable devices.
Engineering Brief 184 (Download now)
EB-1-3 Analogue Hearts, Digital Minds? An Investigation into Perceptions of the Audio Quality of Vinyl—Michael Uwins, De Montfort University - Leicester, UK; University of Huddersfield - Huddersfield, UK
This study investigates the vinyl revival, with particular focus given to the listener’s perception of audio quality. A new album was produced using known source material. Subjects then participated in a series of double-blind listening tests, comparing vinyl to established digital formats. Subsequent usability tests required subjects not only to re-appraise the audio, but also to interact with the physical media and playback equipment. Digital vinyl systems were used in order to investigate the influence of non-auditory factors on their perception of sound quality. Both qualitative and quantitative data was also gathered from subjects of the usability tests, with the correlation (or contradiction) between the results being analyzed. The study concludes that sound quality is not the sole defining factor and that listener preferences are profoundly influenced by other, non-auditory attributes and that such factors are as much a part of the vinyl experience as the music etched into the grooves.
Engineering Brief 185 (Download now)
EB-1-4 Toward the Development of a Universal Listening Test Interface Generator in Max—Christopher Gribben, University of Huddersfield - Huddersfield, West Yorkshire, UK; Hyunkook Lee, University of Huddersfield - Huddersfield, UK
This engineering brief describes HULTI-GEN (Huddersfield Universal Listening Test Interface Generator), a Cycling ‘74 Max-based tool. HULTI-GEN is a user-customizable environment that takes user-defined parameters (e.g., the number of trials, stimuli, and scale settings) and automatically constructs an interface for comparing auditory stimuli, while also randomizing the stimuli and trial order. To assist the user, templates based on ITU-R recommended methods have been included. As the recommended methods are often adjusted for different test requirements, HULTI-GEN also supports flexible editing of these presets. Furthermore, some existing techniques have been summarized within this brief, including their restrictions and how they might be altered through using HULTI-GEN. A finalized version of HULTI-GEN is to be made freely available online at: http://www.hud.ac.uk/research/researchcentres/mtprg/projects/apl/
Engineering Brief 187 (Download now)
EB-1-5 Multidimensional Ability Evaluation of Participants of Listening Tests: Part II—Tomasz Dziedzic, AGH University of Science and Technology - Krakow, Poland; Piotr Kleczkowski, AGH University of Science and Technology - Krakow, Poland
The problem of selecting appropriate participants for a listening test was addressed by the authors' e-brief presented during the 136th AES Convention. After the Convention, the project was continued and the application was further developed. The next stage consisted in the comparison of resolutions in the time and frequency domains for particular listeners. The resolution in time was investigated by a task for gap detection in noise. The resolution in frequency was tested by two tasks: a two-tone detection and distinguishing pitches of two tones. The results showed that there was no correlation between these resolutions (neither negative nor positive), but considerable frequency dependent differences were found. A new version of the test application was developed for this stage.
Engineering Brief 188 (Download now)
EB-1-6 Database of Single-Channel and Binaural Room Impulse Responses of a 64-Channel Loudspeaker Array—Vera Erbes, University of Rostock - Rostock, Germany; Matthias Geier, University of Rostock - Rostock, Germany; Stefan Weinzierl, Technical University of Berlin - Berlin, Germany; Audio Communication Group; Sascha Spors, University of Rostock - Rostock, Germany
A freely available database of measured single-channel and binaural room impulse responses (RIRs and BRIRs) of a 64-channel loudspeaker array of rectangular shape under varying room acoustical conditions is presented. The RIRs have been measured at three receiver positions for four different absorber configurations. Corresponding BRIRs for head-orientations in the range of ±80° in 2° steps with a KEMAR manikin have been captured for a subset of seven combinations of position and absorber configurations. The data is provided in the Spatially Oriented Format for Acoustics (SOFA). It can be used to study the influence of the listening room on multichannel audio reproduction. As an application RIRs for the synthesis of a sound field by Wave Field Synthesis are shown.
Engineering Brief 189 (Download now)
EB-1-7 HAART: A New Impulse Response Toolbox for Spatial Audio Research—Dale Johnson, The University of Huddersfield - Huddersfield, UK; Alex Harker, University of Huddersfield - Huddersfield, West Yorkshire, UK; Hyunkook Lee, University of Huddersfield - Huddersfield, UK
This engineering brief describes a new, open source code library named HAART (Huddersfield Acoustical Analysis Research Toolbox). HAART simplifies the measurement and analysis of multi-channel impulse responses (IRs). For the purposes of this engineering brief the code library is compiled as a set of Max objects that form a prototype program in Max. This program is able to perform the acquisition, manipulation and analysis of IRs using subjective and objective measures described in acoustics literature. HAART is also able to convolve IRs with audio material and, most importantly, able to binaurally synthesize virtual, multichannel speaker arrays over headphones, negating the need for multichannel setups when out in the field. The code library is freely available from: http://www.hud.ac.uk/research/researchcentres/mtprg/projects/apl/
Engineering Brief 190 (Download now)
