Search Results (32)

Room acoustics computer models based on geometrical acoustics usually handle the sound reflections by the assumption of plane waves. However, if the sound source is a point source, which is usually the case, the spherical wave reflection would be more correct. An approximate model for the spherical wave reflection is presented, starting with the assumption of an infinite plane. It was found that the errors caused due to the simplified plane wave assumption can be significant, especially for hard surfaces and near grazing incidence. As something new, the gradual transition from a spherical wave to a plane wave approximation was addressed. For sound propagation exceeding 50 times the wavelength, the plane wave approximation was found to be fully justified, but for shorter distances the spherical wave reflection model should be applied. In contrast to previous work on spherical wave reflection, the reflection from a finite-sized surface was studied. For the first time, the spherical wave reflection model was combined with the complex radiation impedance of a finite-sized surface. One interesting application example of the spherical reflection model is the attenuation of sound propagation above the audience area in a performance space. Finally, the extension of the spherical wave reflection model to higher order reflections was addressed. Full article

Diocletian’s palace with its cellars represents one of the most important cultural heritage sites of the ancient Roman civilisation on the present-day Croatian territory. The cellar complex has been rediscovered only recently and has been preserved remarkably well due to its centuries-long concealment beneath mediaeval urban matrices. An archaeoacoustic analysis was performed on a selected single-nave hall as a small part of this complex. A model of the hall was developed in room acoustics simulation software and calibrated based on the results of field measurements. Acoustic suitability of the hall for speech-based events and music performances was then evaluated according to contemporary objective criteria, and the findings were compared with the results of similar studies performed on other heritage sites. The hall was found to be very well suited for speech in terms of intelligibility and mid-frequency reverberation, thus showing potential for revitalisation, with excessive low-frequency reverberation in the hall and reduced audibility in the farthest part of the audience as potential issues. With a feasible audience size, the hall is not reverberant enough for music performances but provides high clarity. In terms of sound strength, the hall is suitable for solo performers or small ensembles. Excessive perceptive broadening of the sound source is expected due to strong early lateral energy. In terms of traditional Dalmatian a cappella singing, the acoustics of the hall are likely to support and enhance such performances. Full article

Traditional concert-hall evaluations primarily rely on ISO 3382-1 scalar parameters (e.g., C₅₀ and C₈₀), which summarize temporal energy behavior but provide limited insight into the directional composition of early reflections, particularly in geometrically shadowed seating zones. This paper presents a first-order Ambisonics (FOA)-based 3D acoustic sensing framework to diagnose under-balcony directional imbalance, with emphasis on early vertical-reflection deficiency. Scene-based FOA impulse responses (WXYZ) were measured at 11 audience positions (P1–P11) in the National Concert Hall (Taipei) and analyzed using intensity-based direction-of-arrival (DoA) proxies, axis-resolved directional energy build-up, and a distributional descriptor based on directional spatial entropy. Results are presented at three representative frequencies (125 Hz, 1 kHz, and 4 kHz) and analyzed within full (0–200 ms), early (0–80 ms), and late (80–200 ms) windows. While the magnitude proxy $\mid p^{meas}\left(f\right)\mid$ exhibits strong seat-to-seat variability and does not support a uniform attenuation assumption under the balcony, direction-resolved metrics reveal a consistent under-balcony signature. Specifically, the early–late vertical energy discrepancy $\Delta R_z={\displaystyle R_z^{early}}-{\displaystyle R_z^{late}}$ is persistently negative at under-balcony positions (P7–P11) across all three frequencies, indicating a selective reduction in early vertical contribution relative to the late field. Directional entropy analysis further shows predominantly negative $\Delta H_n={\displaystyle H_n^{early}}-{\displaystyle H_n^{late}}$, with more negative values in the under-balcony group, consistent with stronger early directional constraint in shadowed seats. Spatial trend maps are provided via Gaussian RBF interpolation within the audience domain for visualization only. The proposed FOA-based diagnostic framework provides a practical and physically interpretable approach to identify direction-specific early-reflection deficits that remain masked in conventional scalar evaluations, supporting mechanism-oriented assessment and targeted intervention in geometrically constrained listening areas. Full article

The Church of St. Francis in Pula, Croatia, is a well-preserved example of Franciscan gothic sacral architecture from the late 13th century. As preaching was highly valued by the Franciscan order as a way of communicating with the faithful, the study is focused on determining whether speech intelligibility in the church would have been adequate for successful communication between priests and their audience. The archaeoacoustic analysis of the church was performed in four stages: (1) in situ acoustic measurements in the present state, (2) development and calibration of the model of the present state based on measurement results, (3) development of the two models of the presumed historical state based on the calibrated model and historical data, and (4) prediction of acoustic conditions in the present and the historical states in terms of reverberation time T₃₀ and of speech intelligibility in terms of speech transmission index STI. The factors considered in the study were (1) acoustics of the church, (2) profile of the audience (friars and the faithful), (3) layout of the audience areas (choir area in the front of the nave for the friars, back area of the nave for the faithful), (4) positions of the speech sources (altar for addressing the friars, pulpit for addressing the faithful), (5) occupancy (unoccupied and fully occupied church), (6) language used in liturgical ceremonies (Latin and native language), and (7) language proficiency of the audience (native speakers, users of a second language). The results show that (1) fair speech intelligibility (STI ≥ 0.45 for the faithful as native speakers, STI ≥ 0.50 for friars as non-native speakers of Latin) can be achieved for 50% of the audience in the choir area and for the entire audience in the back area in favourable conditions (fully occupied church, audience addressed from dedicated speaker positions), (2) the position of the pulpit (close to the audience and considerably elevated above it) is more favourable than the position of the altar (remote, barely elevated above the audience), and (3) in unoccupied conditions, fair speech intelligibility can still be achieved in at least 50% of the back audience area with the faithful gathered close to the pulpit, while it is not possible for the front audience area addressed from the altar. The summary conclusion is that the church of St. Francis in its presumed historical layout(s) would fulfil its primary function in a limited capacity. Fair speech intelligibility would likely have been sufficient for the audience to follow liturgical ceremonies conducted in the church, but not without difficulty. Full article

In the field of cultural architecture design, the deep impact mechanisms of wooden material design perception on users’ psychological experiences have not yet been fully elucidated. The interior environmental design of concert halls, as venues for immersive artistic experiences, especially the use of natural materials such as wood, is considered a key factor shaping audience perception and experience. However, existing research has largely focused on the acoustic performance of or visual preferences for wooden materials, while there remains a lack of mechanistic explanations for how wooden design perception systematically enhances users’ overall satisfaction through a series of internal psychological processes. Based on the “stimulus–organism–response” theoretical framework, this study proposes a chain mediation model aimed at exploring how perception of wooden design in concert halls enhances user satisfaction by promoting users’ flow experience and subsequently strengthening their place attachment. Through a cross-sectional survey of 1017 audiences with actual experience in wooden concert halls and analysis of the data using covariance-based structural equation modeling, the findings reveal that: (1) perception of wooden design has a significant direct positive effect on user satisfaction; (2) both flow experience and place attachment independently mediate the influence of wooden design perception on user satisfaction; (3) there exists a significant chain mediation path: “perception of wooden design → flow experience → place attachment → user satisfaction”. This study validates, from an architectural psychology perspective, the role of flow and place attachment as consecutive psychological mechanisms. The research provides empirical evidence for architects to use wood as a psychological intervention tool in cultural spaces, transforming material selection from an aesthetic consideration into a systematic design strategy with measurable psychological outcomes. Full article

Currently, there remains a lack of systematic quantitative analysis of the acoustic impact mechanism of ancestral temple theatres in relation to their core function of opera performance. This paper takes the Zhaomutang—a typical ancestral temple theatre in northeast Jiangxi—as an example, and comprehensively uses on-site mapping, impulse response testing, and ODEON three-dimensional sound field simulation to conduct acoustic sensitivity analysis on five key spatial elements of the theatre. The results show that the theatre has a hierarchical sound field pattern along its depth, characterized by “high in the front, low in the rear, stronger on the sides and weaker in the middle”. The front patio and the Xiangtang support the clarity of Gan opera dialogue and the fullness of singing through early lateral reflections and moderate reverberation (EDT of 0.8–1.1 s, C₈₀ of 3.2–6.1 dB). However, the rear patio and the Qintang show apparent loudness deficiency (G of −1.5–3.2 dB) and lack of spatial immersion (LF₈₀ below 0.23). The most effective optimization comes from the reconstruction of the geometric relationship between performers and audience: moving the performers forward and appropriately raising the stage and audience area floor can significantly shorten the rear area EDT and increase C₈₀ and G; in contrast, the improvement in sound quality brought about by adding a patio cover and raising the gables is minimal, and the changes in various parameters are generally less than 1 JND. Based on this, the “schedule priority—reversible intervention” acoustic maintenance strategy for living heritage is proposed, and it is suggested that reversible reflective components be set in the side corridor to specifically enhance the sense of immersion in the rear area sound field. The study constructs a quantitative correlation framework of space, materials, and sound field, providing methodological support and parameter basis for the acoustic assessment and protective utilization of ancestral temple theatres. Full article

Due to the effect of room acoustics on musical interpretation, a musician’s rehearsal may be greatly enhanced by leveraging virtual and augmented reality technology. This paper presents a preliminary study on a rehearsal tool designed for musicians, enabling practice in a virtual acoustic environment with audience-positioned playback. Fourteen participants, both professional and non-professional musicians, were recruited to practice with the rehearsal tool prior to performing in an unfamiliar venue. Throughout the rehearsal, the subjects either played in a virtual environment that matched the acoustics of the performance venue or one that was acoustically different. A control group rehearsed in an acoustically dry room with no virtual acoustic environment. The tool’s effectiveness was evaluated with two 16-item questionnaires that assessed quality, usefulness, satisfaction with the rehearsal, and aspects of the performance. Findings indicate that rehearsing in a virtual acoustic environment that matches the performance venue improves acoustic awareness during the performance and enhances ease and comfort on stage compared to practising in a different environment. These results support the integration of virtual acoustics in rehearsal tools to help musicians better adapt their performance to concert settings. Full article

The existence of echoes in an acoustic event can ruin the capture of a spoken message and the perception of a piece of music. Likewise, in the performers’ area, clear hearing is essential for the coordination and execution of the ensemble. Bullrings are buildings with a circular plan in which echo-encouraging focalisations can occur. Since bullrings lack a roof, the density of reflections is lower than that in a closed area, and therefore strong isolated reflections perceived by the audience as an echo can be created. In this work, calculations of the echo parameter (Echo Criterion EK) and inspection of impulse responses and energy decay curves are obtained in an on-site measurement campaign in the audience zones and in arena areas where the EK parameter exceeds the thresholds. To this end, four bullrings very emblematic of the Iberian Peninsula together with a very prominent Roman amphitheatre in a relatively good state of conservation in the Roman province of Hispania comprise the study cases. Experimental results of the EK parameter and from acoustic simulation in two of the bullrings present good concordance and show that there is no echo for music in any of the venues in the spectator zones and that the most critical area is when source and receiver are both in the arena, where even double and triple echoes appear. Full article

The development of traditional Chinese theatres is closely related to the development of traditional Chinese opera. The acoustic quality of the theatre plays a crucial role in the performance effect of Chinese opera. As one of the five major traditional Chinese opera genres, Yue opera has a significant number of existing traditional theatres in the Shaoxing area. This study conducted on-site measurements of the reverberation time in traditional courtyard Yue opera theatres. The results indicate that the mid-frequency EDT values in the main viewing areas range from 0.6 to 0.7 s, and $T_{30}$ is around 0.7 s. Furthermore, aiming to investigate the optimal reverberation time for Yue opera performance spaces and the factors influencing preferences, subjective experiments using auralization technology and a paired comparison method were conducted. The results show that the optimal reverberation time for Yue opera performance spaces is around 0.8 s. There was no difference in the optimal reverberation time between the ordinary group and the experienced group, but the ordinary group tended to show a higher preference for shorter reverberation times. Compared to singing clips, recitation clips obtained higher preference scores for short reverberation times, indicating that audiences require higher clarity when listening to recitations. Full article

La Banda Primitiva is one of Europe’s most notable symphonic civic bands. Located in Llíria (València, Spain), part of the UNESCO creative cities network, its theater was designed by Joaquín Rieta, one of the most relevant Valencian architects of the twentieth century. This study analyses the current state of the theater, its relevance to the town’s cultural heritage, and how it has evolved over the years in terms of its acoustic performance. The objective is to understand how the theater’s acoustics have evolved over the years and to unveil the reasons behind the preference of the regular audience for specific areas of the venue, considering if these tendencies are influenced by tradition rather than the current auditory experience. The theater’s acoustics were studied with objective and subjective parameters. The objective parameters were assessed by conducting on-site measurements and ray-tracing simulations. One hundred and three musicians answered a survey of auralizations to evaluate subjective acoustic parameters. Three musical pieces were recorded in an anechoic chamber and convoluted by the impulse response of the venue at different positions to obtain the auralizations. The results show that the objective acoustic parameters do not differ significantly. Overall, the reverberation time was longer before the renovation. Regarding subjective testing, the sample only shows a subtle tendency (57%) towards preferring seats on the second balcony. For that reason, it can be concluded that there is no evidence to support the claim that the seats located on the second balcony have better acoustics than those in the stalls. Full article

Rapid technological advances in recent decades have led researchers to refine the accuracy of their studies. In the field of acoustics, the impact of new devices is noticeable, especially in the investigations of cultural heritage buildings. The selection of a seat in theatres and concert halls has always been a concern, since the live experience of artistic performance depends on the quality of hearing and sight view. This paper deals with the elaboration of 360° acoustic maps made in the National Theatre of Zagreb, one of the opera theatres investigated with the Sipario project. The analysis of the main acoustic parameters has been carried out, starting with site measurements describing the acoustic response at various representative points of the main hall by covering the audience area. In addition, acoustic maps have been created for some selected positions based on a 3-degree-of-freedom (3dof) technique that allows a panoramic visualization of the impulse responses (IRs). This methodology completes the determination of early and late reflections that contribute to the acoustic quality of a place. In addition to the interest of experts in acoustics, this methodology can also be adopted by music lovers who can find a reasonable explanation for seat selection when booking their tickets. Full article

Rehearsal rooms play an important role in musicians’ activities to obtain the best results during a performance in front of an audience. Numerous rehearsal rooms are located in complex buildings, such as opera houses and cultural centers, where new research outcomes have led to increasingly complex projects and construction phases. Furthermore, technical complexity has also increased due to the large quantity of used materials and the innovation level of the process. In this context, a new methodology becomes mandatory to control the indoor air quality and the acoustic quality in rehearsal rooms. This paper aims to offer a procedure for rehearsal rooms for large ensembles during the construction and life cycle phases to optimize the indoor environmental quality according to different types of ensembles and repertoires. In particular, rehearsal rooms with wood panel cladding are considered. The proposed methodology is controlled by a digital twin (DT) based on building information modeling (BIM), integrated with acoustic measurements, sensors and actuators aimed at implementing the database in real time. A case study is presented, in which the cladding system is described, the new methodology is applied, and the results are compared with the criteria suggested in the standard ISO 23591. Full article

The bullring of Ronda, one of the oldest in Spain, declared in 1993 as an Asset of Cultural Interest, occupies a paramount place among the buildings of its type thanks to its outstanding beauty. Its configuration as an open-air enclosure with a circular floor plan, as an evocation of the ancient Roman amphitheaters, and its interior with galleries on two levels that house the audience play a fundamental role in the acoustic energy decay and diffusion of the space. The link between architecture and acoustics of the Ronda bullring has been carried out by using on-site measurements and simulation techniques. To this end, an acoustic model is created, which is adjusted by taking the set of 3D impulse responses recorded on-site. The presence of the public and the various sound sources that exist during the bullfight itself are analyzed in the simulations, whereby the conditions of occupation and vacancy are compared, as are the variations due to the location of the sources. Finally, speech intelligibility conditions are simulated with a human directivity source. The precision of the virtual acoustic model enables the sound architecture of this singular space to be ascertained and preserved, thereby incorporating sound as an associated intangible heritage. Full article

Thousands of theatres were built during the Hellenistic period in Greece and overseas colonies. The main elements of the Hellenistic theatre are the following: the orchestra, where music and songs were performed to accompany the acting performance, and the koilon, where the audience sat. Hellenistic theatres were built without any ceiling, with an open-air configuration. This paper reports the acoustic characteristics of the Greek (Hellenistic) theatre located in Morgantina (Sicily, Italy) based on the technical data gathered in different listening positions selected across the sitting area (koilon). The theatre of Morgantina was built in the third century BC and renovated a few decades ago. Nowadays, it is the center of important social and cultural activities. The outcomes of the beamforming technique employed for the survey have been discussed in comparison with traditional acoustic parameters, such as ISO 3382. The scope of this article is to assess the usability of this theatre intended to be used for different types of artistic performances. Full article

The discovery of Roman amphitheaters continues to excite the minds of archaeologists. Within the framework of various excavation campaigns, the architectural requalification of the amphitheater of Durres has been investigated, but no acoustic analyses have yet been carried out. This paper deals with the acoustic reconstruction of the Roman amphitheater of Durres in its original form. A campaign of acoustic measurements was carried out in accordance with ISO 3382 in order to understand the existing conditions, which are very detrimental to any type of live performance. After an accurate analysis of the geometric composition of the building, acoustic simulations were performed to determine the original acoustic response of the building. A comparison of the measured and simulated results, with and without an audience, was made in terms of the main acoustic parameters, while the acoustic map showing the spatial distribution of speech clarity at 1 kHz was added as an alternative way of representing the data. The outcomes show that the results related to the original shape are closer to the optimal values than the existing conditions. Full article