• Spotlight on Broadcasting
• Spotlight on Live Sound
• Spotlight on Archiving
• Detailed Calendar
• Convention Planner
• Paper Sessions
• Exhibitor Seminars
• Application Seminars
• Special Events
• Student Program
• Technical Tours
• Technical Council
• Standards Committee
• Heyser Lecture
Last Updated: 20070320, meiP20 - Psychoacoustics, Perception, and Listening Tests
Monday, May 7, 14:00 — 15:30
P20-1 Detection and Lateralization of Sinusoidal Signals in the Presence of Dichotic Pink Noise—Tuomo Raitio, Heidi-Maria Lehtonen, Petteri Laine, Ville Pulkki, Helsinki University of Technology - Espoo, Finland
This paper investigates the ability to lateralize low-frequency sound in the presence of interfering dichotic noise. This is addressed by measuring the detection and lateralization thresholds of four sinusoidal signals (62.5, 125, 250, and 500 Hz) in the presence of uncorrelated pink noise in headphone listening. In lateralization tests the signals were positioned to left or right by delaying either of the headphone channels by 0.5 ms. The results show that the lateralization threshold does not depart from detection threshold at frequencies 250 and 500 Hz. Interestingly, below 250 Hz the lateralization threshold rises fast, and at 62.5 Hz, the signal has to be amplified 18 dB from the detection level before being lateralized correctly. This suggests that low-frequency ITD decoding mechanisms are easily distracted by random changes in a signal phase. This explains, at least partly, why the direction of a subwoofer cannot be detected easily in surround sound listening of broad-band signals.
Convention Paper 7113 (Purchase now)
P20-2 The Practice and Study of Ear Training on Discrimination of Sound Attributes—Zhi Liu, Fan Wu, Qing Yang, Beijing Union University - Beijing, China
In order to improve subjects’ discrimination of sound attributes, an ear training course has been designed. The training includes: discrimination of a pure tone’s frequency, the frequency changes, sound level changes, musical instrument timbre, irregularity of frequency response. etc. All the items were carried on in interlaced order to avoid listening fatigue. Meanwhile, some explanation of the psychoacoustic principles and some tests were also conducted. In all, 57 subjects, divided into 2 groups, took part in the training course for about 15 weeks. After the special ear training, most subjects made great progress with a nearly 85 percent average correctness rate.
Convention Paper 7114 (Purchase now)
P20-3 The Training and Analysis on Listening Descrimination of Pure Tone Frequency—Zhi Liu, Fan Wu, Qing Yang, Beijing Union University - Beijing, China
After special and scientific ear training, more than 90 percent of people will get great progress on the discrimination of pure tone frequency. This has been proven by long-term ear training for two groups of subjects. Several pure tones were selected in an octave step for the training. Fifty-seven subjects took part in the training. The training was conducted once a week, for a total of 15 weeks for one group. The average correctness rate increased from around 60 percent to above 90 percent. The test results also show that human ears have poor discrimination with middle frequencies, while strong ability with high frequency and low frequencies. The relationship between the improvement and training time indicates that the training has the similar effect as the physical training.
Convention Paper 7115 (Purchase now)
P20-4 Virtual Hearing Aid—A Computer Application for Simulating Hearing Aid Performance—Andrzej Czyzewski, Gdansk University of Technology - Gdansk, Poland; Bozena Kostek, Gdansk University of Technology - Gdansk, Poland and Institute of Physiology and Pathology of Hearing, Warsaw, Poland; Lukasz Kosikowski, Gdansk University of Technology - Gdansk, Poland
The virtual hearing aid is a computer application allowing an approximate simulation of hearing aid performance. The computer application implements algorithms simulating band-pass filters, compressors, and the perceptual masking strategies for audio signal processing. Individual persons' hearing characteristics were taken into account for this purpose. The experimental part comprises verification of engineered algorithms implemented to virtual hearing prosthesis. The paper also contains results of examinations of patients aimed at verifying the applicability of the proposed signal processing strategy to the domain of hearing prostheses.
Convention Paper 7116 (Purchase now)
P20-5 Training Versus Practice in Spatial Audio Attribute Evaluation Tasks—Rafael Kassier, Tim Brookes, Francis Rumsey, University of Surrey - Guildford, Surrey, UK
Listener training in published studies has tended to focus on simple repetitive practice of experimental tasks without feedback. Time savings in listening panel selection and training could be accomplished if a more general training system could be used and applied to a variety of tasks. In order for a training system for spatial audio listening skills to prove effective, it must demonstrate that learned skills are transferable, and it must compare favorably with repetitive practice on specific tasks. A novel study to compare a training system with repetitive practice has been extended to include a total of 48 subjects. Transfer is assessed and practice and training are compared against a control group for tasks involving transfer of spatial audio training.
Convention Paper 7117 (Purchase now)
P20-6 Subjective Assessment of Quality of Multimedia Signals by Means of A-B Test—Stefan Brachmanski, Wroclaw University of Technology - Wroclaw, Poland
In this paper an automated method of subjective assessment of speech, music, image, and video quality has been described. In the method the sound, image or video samples were randomized and paired in A-B sets and then presented to a group of listeners. On the base A-B results a preference matrix was calculated. The conversion from the preference matrix to a numerical scale was performed with accordance to Thurstone's V model of paired comparisons. The method was applied to evaluate an influence of various coding techniques on a quality of video signals and natural speech.
Convention Paper 7118 (Purchase now)
P20-7 Influence of Visual Stimuli on the Sound Quality Evaluation of Loudspeaker Systems—Alex Karandreas, Flemming Christensen, Aalborg University - Aalborg, Denmark
Product sound quality evaluation aims to identify relevant attributes and assess their influence on the overall auditory impression. Extending this sound-specific rationale, the present paper evaluates overall impression in relation to hearing and vision, specifically for loudspeakers. In order to quantify the bias that the image of a loudspeaker has on the sound quality evaluation of a naive listening panel, loudspeaker sounds of varied degradation are coupled with positively or negatively biasing visual input of actual loudspeakers, and in a separate experiment by pictures of the same loudspeakers.
Convention Paper 7119 (Purchase now)
P20-8 The Study of Audio Equipment Evaluations Using the Sound of Music—Shunsuke Ishimitsu, Koji Sakamoto, University of Hyogo - Himeji, Hyogo, Japan; Keitaro Sugawara, Toshikazu Yoshimi, Atusushi Makino, Pioneer Corp. - Kawagoe, Saitama, Japan; Katsuhiro Sasaki, Tohoku Pioneer Corp. - Tendo, Yamagata, Japan; Hirofumi Yanagawa, Chiba Institute of Technology - Narashino, Chiba, Japan
In this paper we considered audio equipment evaluation using musical sounds. Audio amplifiers were set up as the evaluation targets, and sound quality differences between them were visualized by a wavelet analysis using an actual musical sound signal. We considered the cause of these differences and then tried to connect the sound impression to an analysis result. WT of the sound of music was carried out to evaluate two amplifiers. The sound quality of amplifier A related to the esthetic factor of the ”depth” and has been analyzed as the high region of WT, and that of amplifier B related to the force factor and has been analyzed as the low region of WT. Thus, we were able to visualize the impression of listening to the music by correlation of the auditory experiment and wavelet analysis.
Convention Paper 7120 (Purchase now)