# Courtyard Sound Field Characteristics by Bell Sounds in Han Chinese Buddhist Temples
## 1 Introduction
presented a study on the accuracy of predicted acoustical parameters in the Syracuse open-air theatre, with experiments and simulations [21]. [PERSON] dealt with the problem of acoustic correction in historic opera theatres [22]. For sound fields of religious spaces, [PERSON] and [PERSON] analysed the influence of different types of pews on acoustical characteristics of churches [23]. [PERSON] and [PERSON]'s research stated that freely hung textiles may absorb more sound than if the same panel was hung flush to a wall, particularly at higher frequencies; they also showed that the effect of textiles on church acoustics is more evident at medium frequencies than at lower frequencies [24]. Through software simulation, [PERSON] studied the acoustics of 25 box-shaped churches; he believed that length-to-width ratios had a significant influence on C\({}_{80}\) and centre time values [25]. [PERSON] et al. made a comparative analysis of acoustic energy models for churches using measurements from 24 Italian churches that differed in style, typology, and location [26]. [PERSON] et al. stated that acoustics in churches are fundamentally associated with the way these churches are covered [27]. [PERSON] and [PERSON]'s research showed that churches with a vaulted nave have considerably longer RT values, while wooden ceilings with painted canvases caused significant RT reduction, particularly at medium and low frequencies [28]. [PERSON] and [PERSON] conducted an acoustic survey in a church in Brazil that has a modern architectural style in order to assess the acoustic quality of the nave [29]. [PERSON] and [PERSON] took acoustical measurements based on impulse responses in two churches in Hong Kong, and their analysis was concentrated on RT, early decay time (EDT), C\({}_{80}\), early-to-late ratio, and integrated decay [30]. [PERSON] and [PERSON] investigated and analysed the acoustic properties of Polish Roman Catholic churches, and the index they proposed can be used in simulation investigations and to forecast acoustic quality changes [31]. [PERSON] et al. presented a study to analyse church bell noises and sleep disturbances of nearby residents [32]. [PERSON] et al. found that in Japanese churches, changes in the direction could improve the intelligibility of speech. By contrast, source location had relatively little effect on acoustic parameter values [33]. [PERSON] et al. summarised principal contributions to the acoustics of ancient occidental Christian churches in recent decades [34]. [PERSON] et al. analysed the sound field characteristics of a large hollow stup in an Indian Buddhist temple in Nagpur by means of an in situ measurement and simulation, and investigated the effects of these characteristics on religious activities [35]. [PERSON] and [PERSON] discussed the current sound systems in mosques, and introduced the effect of these systems on the mosques' applicable sound parameter [36]. These different religions adopted different worship rituals and architectural space; however, all these studies have shown that the appropriate sound field is important for creating a religious atmosphere, and is thus significantly related to our study. Although many previous results are related to sound fields of gardens, traditional outdoor performance spaces, and interior sound fields of churches, these research subjects are significantly different from the courtyards of Han Chinese Buddhist temples in terms of courtyard layout, sound source characteristics, and the arrangement of sound absorbers. Therefore, from a spatial perspective, research on Han Chinese Buddhist temples' courtyard sound fields is still lacking. This study focuses on courtyard sound fields of Han Chinese Buddhist temples and employs acoustic software (ODEON 13.02, Copenhagen, Denmark) to simulate typical courtyard sound fields, with the aim of revealing the effects exerted by temple layouts, various spatial elements, and sound sources. First, sound fields of three traditional courtyards are measured.