Acoustic Impressions Research Articles

The Bacinete Main Shelter: A Prehistoric Theatre?

In the last few years, archaeoacoustic studies of rock art sites and landscapes have undergone significant growth as a result of renewed interest in the intangible aspects of the archaeological record. This article focuses on the acoustic study carried out in the rock art complex of Bacinete, Cádiz (Spain). After describing the archaeological site and its importance, a representative set of monaural and spatial IRs gathered onsite is thoroughly analysed to explore the hypothesis that the sonic component of the site played an important role in how prehistoric people interacted with it. Additionally, we briefly discuss the challenges of analysing the acoustics of open-air spaces following the recommendations of the ISO 3382-1 guidelines, a standard developed not for open-air spaces, but for room acoustics. The results obtained confirm the favourable acoustic conditions of the Bacinete main shelter for speech transmission. The different subjective acoustic impressions obtained in a somewhat similar shelter located nearby, Bacinete III, are also explained, alluding to a lesser degree of intimacy felt in the latter.

PSYCHO-ACOUSTIC ASSESSMENT OF VIOLINS WITH DIFFERENT ANATOMICAL FEATURES OF WOOD

In this paper, the manufacturing technologies of violins, followed by a study on the psycho-acoustic evaluation of violins with different anatomic structure of wood are presented. The evaluation was performed by music experts (performers, teachers, students) based on music auditions of excerpts recorded on the violins studied. The musical performance was performed by the same violinist, under the same conditions. Respondents rated five acoustic criteria. The statistic results showed that age, experience, gender influence the acoustic perception and also that the geometric characteristics of the violins produce different acoustic impressions.

Chamber musicians' acoustic impressions of auditorium stages: Relation to spatial distribution of early reflections and other parameters.

Characterizing stage acoustics using objective parameters has seen some recent resurgence-several studies have noted the importance of the directionality of early stage reflections to musicians, which is not adequately represented using existing omnidirectional stage-support parameters. This study examines the subjective impressions of 19 chamber musicians against omnidirectional [reverberation time, early and late support (STEarly, STLate), etc.], and proposed spatially-defined parameters (TH and TS), along with simple ratios of stage dimensions derived from measurements on eight purpose-built stages. TH is a ratio of early energy from "above" to that from the "horizontal," while TS relates energy from above to that from the "sides" of the stage. Robust mixed-effects analyses showed that the musicians' overall acoustic impression ratings are predicted (i) by TH within a linear model; (ii) by TH × STEarly,TH × STLate, and TS × STEarly,TS × STLate; (iii) by STEarly, STLate each within parabolic models; and (iv) by several architectural parameters' linear and parabolic models. These findings reinforce recent studies of spatially-defined parameters to more fully account for the subtleties of onstage sound fields. Some simple design recommendations are presented, although future studies are needed to confirm these findings/recommendations for a wider range of auditorium stages.

Modification of the head-related transfer functions for auditory proximity in rooms

The human hearing uses two signals entering the ears to interpret surrounding spaces and sound sources, and certain acoustic impressions are often regarded favorably by the listeners. At times, music consumers may consider auditory proximity and intimacy as a desired sensation. In some scenarios, the acoustic reflections, often arriving from lateral angles, succeed in enhancing the perceived proximity, even though all acoustic events occur at far distances. In contrast, natural sounds emanating from a very close proximity are instinctively perceived as intimate. The perception of spatial sound is based on the binaural cues, which can be modeled with head-related transfer functions (HRTF). Earlier research has demonstrated that the interaural level difference for lateral incidence is the foremost difference between near and far-distance HRTFs. In the context of room acoustics, only lateral reflections arrive from angles which at high frequencies create traces of interaural level difference otherwise characteristic to near-field HRTF. This paper explores altering the auditory proximity of auralizations by introducing near-field-type interaural level differences to widely available far-field HRTFs. Analysis of the application of these modified HRTF to reflected sound provides more insight into the sources of auditory proximity.

Acoustic characteristics of ataxic speech in Japanese patients with spinocerebellar degeneration (SCD)

In English- and German-speaking countries, ataxic speech is often described as showing scanning based on acoustic impressions. Although the term 'scanning' is generally considered to represent abnormal speech features including prosodic excess or insufficiency, any precise acoustic analysis of ataxic speech has not been performed in Japanese-speaking patients. This raises the question of what is the most dominant acoustic characteristic of ataxic speech in Japanese subjects, particularly related to the perceptual impression of 'scanning'. The study was designed to investigate the nature of speech characteristics of Japanese ataxic subjects, particularly 'scanning', by means of acoustic analysis. The study comprised 20 Japanese cases with spinocerebellar degeneration diagnosed to have a perceptual impression of scanning by neurologists (ataxic group) and 20 age-matched normal healthy subjects (control group). Recordings of speech samples of Japanese test sentences were obtained from each subject. The recorded and digitized acoustic samples were analysed using 'Acoustic Core-8' (Arcadia Inc.). Sentence duration was significantly longer in the ataxic group as compared with the control group, indicating that the speaking rate was slower in the ataxic subjects. Segment duration remained consistent in both vowels and consonants in the control group as compared with the ataxic group. In particular, the duration of vowel segments, i.e. the nucleus of Japanese mora, was significantly invariable in the control group regardless of differences between subjects as well as in segments compared with the ataxic group. In addition, the duration of phonemically long Japanese vowels was significantly shorter in the ataxic group. The results indicate that the perceptual impression of 'scanning' in Japanese ataxic cases derives mainly from the breakdown of isochrony in terms of difficulty in keeping the length of vowel segments of Japanese invariable during speech production. In addition, the tendency toward irregular shortening of the length of phonemically long Japanese vowels is thought to reinforce the impression of 'scanning' in ataxic speech in Japanese cases.

Comparisons of Auditory Impressions and Auditory Imagery Associated with Onomatopoeic Representation for Environmental Sounds

Humans represent sounds to others and receive information about sounds from others using onomatopoeia. Such representation is useful for obtaining and reporting the acoustic features and impressions of actual sounds without having to hear or emit them. But how accurately can we obtain such sound information from onomatopoeic representations? To examine the validity and applicability of using verbal representations to obtain sound information, experiments were carried out in which the participants evaluated auditory imagery associated with onomatopoeic representations created by listeners of various environmental sounds. Results of comparisons of impressions between real sounds and onomatopoeic stimuli showed that impressions of sharpness and brightness for both real sounds and onomatopoeic stimuli were similar, as were emotional impressions such as "pleasantness" for real sounds and major (typical) onomatopoeic stimuli. Furthermore, recognition of the sound source from onomatopoeic stimuli affected the emotional impression similarity between real sounds and onomatopoeia.

Visualization methods of direct and early reflection sounds in small enclosures

Many parameters exist for evaluating large sound fields such as concert halls. However, it is difficult to apply those parameters for evaluation of a small room such as a recording studio because of their different sound fields. Widely useful common parameters have not been established. Moreover, early reflections are important in small rooms for determining spatial acoustic impressions. Therefore, various methods that visualize spatial acoustic information obtained by early reflection in rooms are proposed. For this study, sound fields (a music studio and a filmmaking studio) were measured using three kinds of different techniques: instantaneous intensity, mean intensity, and a sphere-baffled microphone array. This report compares the information of sound source directions obtained using these methods. Results show that every method can estimate the position of sound sources and important reflections with high accuracy. In the future, we shall propose a method that visualizes spatial acoustic information more precisely by combining the methods and establishing acoustic parameters that are available for evaluating and designing small rooms.

The Sound of Colour

AbstractIn our subjective perception, visual and acoustic impressions are linked. Sounds and pictures — a new study of their interaction provides a basis for product optimisation

Laryngeal gestures of traditional Japanese singing

Needless to say, each nation has its own culture, including singing style. In Japan, various singing styles have been inherited over long periods of time. This study attempts to record the laryngeal gestures for performing traditional singing. Laryngeal gestures were monitored by fiberscope and recorded onto an ordinary video recorder with audio signals. Care was taken for singers to perform naturally. Since the singing method is so different from that of the Western operatic style, there have been discussions about vocal hygiene. Sometimes the singing voice used in traditional Japanese songs gives creaky, strained, or pressed acoustic impressions to the audience. Observing the laryngeal gestures during a performance, hyperadduction of the vocal fold, false vocal fold, or tight closure of the glottis, which are supposed to suggest hyperfunction of the larynx, was rarely observed. This observation suggests that the traditional Japanese singing style agrees with vocal hygiene; otherwise it could not be traditional. [Work supported by Grant-in-Aid for Scientific Research from Ministry of Education, Science and Culture No. 08457449.]

An improved geometrical sound field analysis in rooms using scattered sound and an audible room acoustic simulator

A geometrical computer simulation model and an audible room acoustic simulator, based on ray tracing with scattering effects, are presented. This calculation model classifies the receiving sound energy into three types. Direct sound energy is calculated with the inverse square law, and early reflected and diffuse sound energy are calculated with the effective geometrical reflection energy coefficient using a simple diffraction theory for a finite free reflecting panel. Two actual halls are used to compare measured and computed values of four acoustic parameters: Clarity (C), deutlichkeit (D), lateral efficiency (LE), and room response (RR). It has been found that the new calculation model is a better evaluator of C, D and RR than the traditional ray tracing method. The room acoustic simulator has been used to simulate sound in the halls using 15 channels. The simulator can judge acoustic impressions in the presence of reverberation, clarity and spaciousness.

Nose and nasality.

The term derived from Latin nasus (nose), seems to serve excellently the purpose of characterizing certain acoustic impressions of abnormal speech. Yet science also asks for a definition of a term. Now either the term nasality suggests a very unclear definition, namely, something abnormal going on in the nose, or the term proves to be wrong after an exact definition of the condition has been found. Observation shows that there are fundamentally two entirely different acoustic impressions that indicate something going on in the nose. Furthermore, normal speech also sometimes produces the impression of something going on in the nose. The latter fact also could suggest the use of the term nasality, and certainly the same term should not be used for normal and abnormal conditions. The impression of something going on in the nose in normal speech can, if well defined, serve as a starting point for

Acoustic impressions during chloroform narcosis

Acoustic impressions during chloroform narcosis