Saturday, October 11 9:00 am 12:00 noon
Session F Psychoacoustics, Perception, and Listening Tests, Part 1
F-1 Auditory Perception of Nonlinear DistortionTheoryEarl R. Geddes, GedLee LLC, Northville, MI, USA; Lidia W. Lee, GedLee LLC, Northville, MI, USA; Eastern Michigan University, Ypsilanti, MI, USA (Invited)
Historically, distortion has been measured using specific signals sent through a system and quantified by the degree to which the signal is modified by the system. The human hearing system has not been taken into account in these metrics. Combining nonlinear systems theory with the theory of hearing a new paradigm for quantifying distortion is proposed.
F-2 Auditory Perception of Nonlinear DistortionLidia W. Lee, Eastern Michigan University, Ypsilanti, MI, USA; Earl R. Geddes, GedLee LLC, Northville, MI, USA (Invited)
A new metric to the perception of distortion was recently proposed by Geddes and Lee (2003). Psychoacoustical data were measured, correlation and regression analysis were applied to examine the relationship and predictive value of this new metric to the subjective assessment of sound quality of nonlinear distortion. Furthermore, conventional metrics such as total harmonic distortion (THD) and intermodulation distortion (IMD) were also compared. Thirty-four listeners participated in a listening task, rating 21 stimuli using a 7-point scale. No significant relationships were observed when comparing the subjective ratings with TDH and IMD metrics. Significant correlation (r=0.95, p<.001) was observed between the subjective ratings and the new proposed GedLee (Gm) metric. Furthermore, robust predictive power was verified utilizing the GedLee metric. GedLee metric has demonstrated remarkable potential to quantify sound quality ratings of nonlinear distortion.
F-3 The Subjective Loudness of Typical Program MaterialGilbert A. Soulodre, Michel C. Lavoie, Scott G. Norcross, Communications Research Centre, Ottawa, Ontario, Canada
In many applications it is desirable to measure and control the subjective loudness of audio signals. However, there is a lack of data regarding loudness perception for typical program material, and an ITU-R study is underway to examine this matter. In the present paper a series of formal subjective tests were conducted to evaluate the perceived loudness of a broad variety of typical program materials, including music and speech. Subjects adjusted the level of various audio materials until their perceived loudness was equal to that of a reference signal. Tests were designed to examine the relative subjective loudness for a variety of playback conditions. The just noticeable differences (JND) in perceived loudness was also examined.
F-4 A Calibrated Source for Virtual Audio PrototypingKalle Koivuniemi, Nick Zacharov, Nokia Research Center, Tampere, Finland
This paper describes the design of a Calibrated Source (CalSo) loudspeaker created for audio prototyping of a mobile phone. CalSo is used in conjunction with a PC application, which enables the use of virtual audio prototypes for the enhancement of audio content creation of mobile phones. CalSo provides means to calibrate the output of a PC with the loudspeaker itself or with a pair of headphones. CalSo was primarily developed to ensure that the auralized audio output of a virtual audio prototype from the users PC accurately reproduces the audio output of the real device.
F-5 Augmentation, Application, and Verification of the Generalized Listener Selection ProcedureDavid Isherwood, Gaëtan Lorho, Ville-Veikko Mattila, Nick Zacharov, Nokia Research Center, Tampere, Finland
The generalized listener selection procedure (GLS) defines criteria for the efficient creation of a permanent listening panel. This paper describes the application of this procedure to a large group of candidate listeners (>300) from which a permanent panel of 30 listeners was to be formed. The criteria presented in the original publication are augmented to make the procedure more rapid and sensitive to acuity of specific auditory precepts. Verification of the benefits of such a procedure based on a comparison of listening test results for the final GLS panel and a panel of randomly chosen listeners is presented.
F-6 Relating Multilingual Semantic Scales to a Common Timbre Space: Part II Charith N. W. Giragama, University of Aizu, Aizu-Wakamatsu, Fukushima-ken, Japan; William L. Martens, McGill University, Montreal, Quebec, Canada; Susanta Herath, St. Cloud State University, St. Cloud, MN, USA; Dishna R. Wanasinghe, Alam M. Sabbir, University of Aizu, Aizu-Wakamatsu, Fukushima-ken, Japan
A single, common, timbre space for a small set of processed guitar sounds was derived for four groups of listeners, each group comprising respectively native speakers of English, Japanese, Bengali, a language of Bangladesh, and Sinhala, a language of Sri Lanka. Members of these four groups also made ratings on 10 bipolar adjective scales for the same set of sounds, each of the four groups using anchoring adjectives taken from their native language. Whereas the two primary dimensions underlying perception of the guitar timbres was common between the four groups, the way in which directly translated adjectives were used to describe the sounds generally differed between the groups, those differences being quantified via principal components analysis. Nonetheless, the two most closely related languages, Bengali, and Sinhala (both Indo-Aryan languages), showed much more semantic similarity to each other than did the Japanese language with any of the three other languages examined.