Optimization of Architectural Electroacoustics Design for the Interior Mezzanines of Vertical Buildings

A science that deals with the transformation of electrical energy into acoustic energy or vice versa, electroacoustic, generates the increased intensity and loudness of sound by mechanical and/or electrical means. Because of the same context, it should be designed simultaneously with the consideration of room acoustics. A vertical building is usually designed separately with architectural aspect and other technical consideration. Interior mezzanine has unique characteristic on propagating sound because its balconies could be an element of room acoustic reflector and absorber, a shelter from noise and a barrier of sound propagation. For optimum music and speech activities, hybrid design strategy of active strategy using electroacoustic combined with the passive method is conducted. This research optimizes room acoustics criteria of variated building models as integrated building system with the loudspeaker. Ecotect Analysis and additional audio programming determine all process by simulating all potential variables. The result shows that 5 m will be the recommended minimum distance of column-loudspeaker placement for mezzanine floor. With the same loudspeaker specification power and frequency, the vertical structure as the armature of electroacoustic orientation and interior material are the most critical variables in determining of reverberation time optimization.

Architectural electroacoustics; Interior mezzanine; Loudspeaker design; Reverberation time; Vertical buildings

Currently, the relationships between passive and active systems, room acoustics and electroacoustics involve many issues, even if it is a fact that in room acoustics, modern techniques for its measurement could not exist without the aid of sound system components such as loudspeakers, microphones and electronic controllers. Whatever the characteristics of the type and purpose of an amplification system, there is a close interface between the system and the room in which it operates. Its performance depends on the high point of the attachment on the acoustical properties (Kuttruff, 2009). Therefore, the component installation and use of the system should involve careful acoustical design, both technically and aesthetically. In the relationship with architectural elements, room geometry, represented by the dimensional aspect of room acoustics, plays an important role in sound propagation control. According to Zhao et al. (2017), in a large building, whatever its internal activities, length and height have the ability to control sound pressure levels.

In a  model of  acoustical path representing  the physical  world,  Kleiner (2013) suggests  that it should use acoustical components in order to simplify understanding of the process of the paths. The hybrid design of acoustics and electroacoustics provides a more reliable and complete characterization of a system than either one of these spectroscopes separately. A vertical building is usually designed separately from the architectural aspect and other technical considerations, such as building utility. As mentioned by Spaeth (2015), the design of acoustic spaces is an equal challenge for both architects, architecturally and aesthetically, and for engineers, in the technical sense, because of the complexity of the many interconnected factors. Furthermore, it is difficult to estimate how adaptations effect the various designs of the overall acoustic properties as the architectural design progresses, and acoustic design on vertical spaces should serve as starting points for architectural design solutions.

Generally, professional amplification systems can help to achieve the appropriate loudness and sound balance for audiences. Moreover, a stability of sound with an appropriate amount of echoing should be designed, and fine sound naturalness, consistent with room image, should be aimed for. In detail, the results show that 5 m is the recommended minimum distance of column-loudspeaker placement for mezzanine floors. At the same time, the required RT suggests 4?8 m to be the recommended range. With the same loudspeaker specifications of power and frequency, the vertical structure could be the armature of electroacoustic orientation, and the interior material is the most critical variable in determining reverberation time optimization. The combination of passive and active methods is recommended for better sound propagation in vertical buildings. Furthermore, implementation of electroacoustics as active systems should enhance either the stage or the audience sound, and provide the same control of sound as passive acoustic design. In the near future, this study will be extended to analysis of the integrated design of room acoustics, and thermal issues such as ventilation systems, as a thermo-acoustic analogy for high interior mezzanines. It will be very advantageous to obtain a more realistic approach to the combination of architectural and technical issues in buildings. Integrated with attention to energy efficiency, this project intends to achieve a hybrid method as a compromise strategy for a better living environment.

This research is part of Excellent Primary Research of Higher Education, Penelitian Dasar Unggulan Perguruan Tinggi No. 882/PKS/ITS/2018. The authors gratefully acknowledge this financial and technical support.

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