• The Journal of the Acoustical Society of Korea
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• v.42 no.6
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• pp.617-626
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• 2023

This study aims to investigate the preferred sound level of water sound for various levels of open-plan-office noise regarding soundscape quality and speech privacy. And assessment of the work efficiency of the water sound. For the laboratory experiment, office noise was recorded using a binaural microphone in a real open-plan office. For the assessment of the soundscape quality and speech privacy, Overall Soundscape Quality (OSQ) and Listening Difficulty (LD) were evaluated under three different sound levels (55 dBA, 60 dBA, and 65 dBA) and five different signal-to-noise ratios (SNR -10 dB, -5 dB, 0 dB, +5 dB, and +10 dB). After the evaluation, the preferred SNR was proposed according to OSQ and LD. For the assessment of to work efficiency of water sound, this study evaluated the cognitive performance of both of the condition noise only and combine the water sound with office noise. The results showed that LD increased as the water sound level increased, but OSQ decreased. When the water sound level was more than the office noise level, the OSQ decreased from noise only. Therefore, considering OSQ and LD, the preferred SNR of water sound was -5 dB for all noise levels. At the preferred level of water sound, the cognitive performance results were shown to decrease at 55 dBA compared to noise only, but at 60 dBA and 65 dBA combine the water sound results were increased than the noise only.

• The Journal of the Acoustical Society of Korea
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• v.7 no.4
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• pp.5-12
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• 1988

In order to know the preferred delay time of single reflection in relation in relation to the source signal, and to investigate whether or not there is any display in preference judgment of sound field between subjects of different nationalities, tests of subjective preference for musical sound fields with single reflection were preformed. The result showed that the preferred delay times agreed with the effective duration of auto-correlation function of the source signals, when the amplitude of reflection relative to the direct sound is 0dB. No fundamental disparity in series of judgement of sound field was found even for different series of Judgment with different music motifs. The result of preference test using different passages in single music showed that the fluctuation of the effective duration autocorrelation function over all the passages of the music was small. Thus, the preferred delay time can be determined by the coherence of autocorrelation function of the source signals and the amplitued of reflection.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.722-725
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• 2006

Studies on the ways to construct agreeable sound-amenity have been processed in Korea recently and Virtual Acoustics Field Simulation System (VAFSS) which is an active acoustics reproducing system has been made as a technique to realize the results of the study. This system catches the changes of surroundings and produce sounds which go well with the mood of the space. The fact that a man thinks a sound goes well with factors of the environment should be an individual evaluation. Thus, the standards to classify factors influencing the preference of the sound, which can be judged by the environment, are needed. This study suggests the standards of factors to provide agreeable sound for people according to changes of the time and other elements. Among the factors influencing environment, the temperature, the humidity and the wind were suggested as standards of discomfort Index and wind chin temperature. Besides, only the intensity of illumination has been chosen to estimate the intensity of radiation as a part of factors of the whether.

• Journal of the Ergonomics Society of Korea
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• v.27 no.3
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• pp.61-69
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• 2008

The purpose of this study was to examine the effects of sensibility and compatibility from function sounds of mobile phones. For this purpose, the present study extracted sensibility adjectives and carried out sensibility evaluation to identify the sensibility factors in the function sounds of mobile phones. And 65 sound sources out of six categories were investigated for 27 subjects. The result showed that two dominant sensibility factors were the duration and the melody pattern of the sound sources. The compatibilities of opening and closing sounds were evaluated lowly with short duration and quick tempo. Especially, the most of the subjects preferred more attractive and longer opening sounds than other function sounds. Another finding was that the short sounds with melodies were preferred for cancellations and alerts, unliked the commonly used sound sources in industry and other traditional electronic products.

• Fibers and Polymers
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• v.6 no.3
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• pp.269-276
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• 2005

In this study, cross-cultural comparison of sound sensation for Korean traditional silk fabrics between Korea and America was performed and prediction models for sound sensation by objective measurements including sound parameters such as level pressure of total sound (LPT), Zwicker's psychoacoustic characteristics, and mechanical properties by Kawabata Evaluation System were established for each nation to explore the objective parameters explaining sound sensation of the Korean traditional silk. As results, Koreans felt the silk fabric sounds soft and smooth while Americans were revealed as perceiving them hard and rough. Both Koreans and Americans were pleasant with sounds of Gongdan and Newttong and especially Newttong was preferred more by Americans in terms of sound sensation. In prediction models, some of subjective sensation were found as being related mainly with mechanical properties of traditional silk fabrics such as surface and compressional characteristics.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.682-685
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• 2005

In this research, how the evaluation of the spacial image influenced by the environmental friendly elements included in the visual information, and how the selection of the sound changed depending on the characteristics of spatial image by the 40 subjects were carried out. Vast tracts of green land and the waterfront were highly preferred and impressive than the other spaces. The green music, signal with water sound and bird chirping sound were highly scored. In the frequency characteristics of the factors, the first factor was artificial sound(high at the low frequency band), the second was natural sound(uniform at all frequency band) and the third was water sound(high at the middle and high frequency band over 500Hz). This shows that the proposal of the sound which has the frequency characteristics fit to the spacial image should be selected for the soundscape of the target space.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.401-405
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• 2003

Sound quality is becoming a major concern in optical disc drives (ODD). In order to improve the sound quality of slim type ODDs, we changed lead screw pitch and firmware algorithm in the seek mode. To evaluate the sound quality, the PCM (Paired Comparison Method) was adopted and the result was compared with the time-averaged loudness spectrum. Sound signals were also recorded and modified by increasing or decreasing selected frequency bands to verify their sensitivities to the sound quality. As a result of jury test, preferred frequency bands are associated with the time-averaged loudness spectrum.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.5 s.110
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• pp.551-558
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• 2006

Noise from air-conditioner system installed in the ceiling of a classroom was evaluated to investigate the sound quality of air-conditioning noise. Harmonics of air-conditioning noise were removed and the sound pressure levels of the frequency bands from $250{\sim}630Hz$ were changed to control sound quality. Evaluation for refreshing sensation was conducted using a paired comparison method and the results showed that noise without harmonics were preferred to noise with harmonics. The noises which have larger level increases to the unchanged noise at $250{\sim}630Hz$ were evaluated better in both of the noises with and without harmonics. Results of multiple regression analysis on psychoacoustic parameters and subjective preferences showed sharpness as a major affecting factor in describing the refreshing aspect of air-conditioning sound.

• KIEAE Journal
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• v.12 no.4
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• pp.83-88
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• 2012

As for the generally preferred sound sources used in the test, the sound of water and the birds chirping were highly valued. And they have found that preference of the subject is increased if background music which mixed well with the sound sources were provided together. On the other hand, the sound sources of low satisfaction were judged at be church bells, bell of Emile, and fulling cloth, which not mix well with interior landscaping. If the physical elements of interior landscaping were equally composed, it has found that the larger were a of water space is, the higher satisfaction more than other sound sources. Average satisfaction of background sound in interior landscaping classified according to the characteristics of space has found that satisfaction of the birds chirping and music in working space and satisfaction of water sound and music in commercial space were high. Women judged that satisfaction of the birds chirping and music in working space and satisfaction of water sound and music in commercial space whose values were the same with the average ones were high, while men judged that satisfaction of the song of birds and music in working and commercial space is high.

• ETRI Journal
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• v.22 no.2
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• pp.11-19
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• 2000

If the right and left signals of a binaural sound recording are reproduced through loudspeakers instead of a headphone, they are inevitably mixed during their transmission to the ears of the listener. This degrades the desired realism in the sound reproduction system, which is commonly called 'cross-talk.' A 'cross-talk canceler' that filters binaural signals before they are sent to the sound sources is needed to prevent cross-talk. A cross-talk canceler equalizes the resulting sound around the listener's ears as if the original binaural signal sound is reproduced next to the ears of listener. A cross-talk canceler is also a solution to the problem-how binaural sound is distributed to more than 2 channels that drive sound sources. This paper presents an effective way of building a cross-talk canceler in which geometric information, including locations of the listener and multiple loudspeakers, is divided into angular information and distance information. The presented method makes a database in an off-line way using an adaptive filtering technique and Head Related Transfer Functions. Though the database is mainly concerned about the situation where loudspeakers are located on a standard radius from the listener, it can be used for general radius cases after a distance compensation process, which requires a small amount of computation. Issues related to inverting a system to build a cross-talk canceler are discussed and numerical results explaining the preferred configuration of a sound reproduction system for stereo loudspeakers are presented.