Last Updated: 20060821, mei
Friday, October 6, 8:30 am — 11:30 am
Chair: Sean Olive, Harman-JBL - Northridge, CA, USA
P6-1 Investigation of Hearing Loss Influence on Music Perception, in Auditoria, by Means of Stereo Dipole Reproduction—Andrea Capra, Marco Binelli, Daniela Marmiroli, Paolo Martignon, Angelo Farina, University of Parma - Parma, Italy
A large number of people who sit in theaters or in auditoria do not have an optimal perception of sound because of hearing loss. So, in order to find a correlation between objective parameters and subjective descriptors, executing therefore meaningful listening tests, we need to first study the perception of the customer. For this purpose, selected theatergoers, different in age, sex, and degree of hearing perception, were chosen as subjects. The listening test was based on the virtual spatial recreation of several theaters, by means of an optimized stereo dipole technology. The test was repeated with 30 subjects with and without hearing aids, which were previously set to compensate for the auditory loss. Some preliminary data analysis results are shown.
Convention Paper 6887 (Purchase now)
P6-2 Audibility of Linear Distortion with Variations in Sound Pressure Level and Group Delay—Lidia Lee, Eastern Michigan University - Ypsilanti, MI, USA; Earl Geddes, GedLee LLC - Northville, MI, USA
Recent psychoacoustic studies of nonlinear distortion have yielded some new insights into what audible problems in loudspeakers might be related to. This paper will show the results of recent subjective tests that extend the work of various previous works to show that sound level significantly affects the perception of linear distortion in audio systems. This means that the hearing system itself is nonlinear, and what has been thought of as being nonlinear distortion in the audio system may actually be a nonlinear perception directly in the receiver itself.
Convention Paper 6888 (Purchase now)
P6-3 Development and Evaluation of Short-Term Loudness Meters—Gilbert Soulodre, Michel Lavoie, Communications Research Centre - Ottawa, Ontario, Canada
Recently, much effort has been devoted to developing and evaluating an algorithm that can accurately measure the long-term loudness of mono, stereo, and multichannel audio signals. This has resulted in a new ITU recommendation that provides a single loudness reading for the overall audio sequence. In many applications it is desirable to also have a measure that can continuously track the short-term loudness of the audio signal over time. Such a meter would be used in conjunction with existing metering methods to provide additional information about the audio signal. In the present paper subjective test methods are devised to aid in the development of a short-term loudness meter. Subjective methods for evaluating the meter’s performance are also explored.
Convention Paper 6889 (Purchase now)
P6-4 Headphones Listening Tests—Martin Opitz, AKG Acoustics GmbH - Vienna, Austria
In the present paper a dedicated listening environment for the subjective evaluation of headphones is described. Focus is on the subjective sound quality of different headphones. The listening environment comprises a dedicated playback-system in a reference listening room. A software package consisting of three parts is developed allowing the design, execution, and postprocessing of headphones listening tests. The first experience with this tool and the results of subjective audio ratings for four different headphones are described. Factorial analysis of the obtained responses suggests that a projection of the ratings in a two-dimensional factorial space results in negligible loss of information. The benefit of a new membrane technology results in significantly improved subjective ratings of the respective headphones.
Convention Paper 6890 (Purchase now)
P6-5 Distance Perception of Phantom Sound Images Presented by Multiple Loudspeakers Placed at Different Distances in Front of a Listener—Reiko Okumura, Kimio Hamasaki, Kohichi Kurozumi, NHK Science & Technical Research Laboratories - Tokyo, Japan
Distance perception of the composite sound image reproduced by multiple loudspeakers, which were placed facing (near and far) a listener on a horizontal plane, was investigated. The multiple loudspeakers were placed at different distances in front of the listener and reproduced both phantom and real sound images. The results of subjective evaluations showed the possibility that phantom sound images could be composed by the near and far loudspeakers and that listeners could distinguish their distance from it among the real sound images presented by each loudspeaker.
Convention Paper 6891 (Purchase now)
P6-6 Implementation of Swing Sound Image and its Localization Accuracy in Two-Channel Stereo Sound Reproduction—Akihiro Kudo, Seiya Kubo, Haruhide Hokari, Shoji Shimada, Nagaoka University of Technology - Nagaaoka, Niigata, Japan
In virtual sound reproduction with headphones, a well-known problem is that using nonindividualized head-related transfer functions (HRTFs) yields front-back confusion in sound image localization. To overcome this problem, a swing sound image method has already been reported that significantly reduces the front-back confusion in single sound source reproduction. In order to apply the method to two-channel stereo sound reproduction, this paper proposes two methods of producing the swing sound image: the twist and compand methods. Three listening tests are used to assess their localization accuracy. The results show that, with suitable parameters, these methods can reduce front-back confusion.
Convention Paper 6892 (Purchase now)
