Problem

Echoes

Echoes have long been concern of architects and designer of multi-purpose hall. Echoes form speech waves as they reflected from the floor, walls, and other neighbouring object. If reflected waves arrives a very short time after the direct sound, it is perceived not as an echo but as a spectral distortion, or reverberation. Echoes are invariably annoying, and under extreme conditions can completely disrupt a conversation.

According to J. Benesty, if so many reflections arrive at a listener that they are unable to distinguish between them, the proper term is reverberation. An echo can be explained as a wave that has been reflected by a discontinuity in the propagation medium, and returns with sufficient magnitude and delay to be perceived. Echoes are reflected off walls or hard surfaces such as wood, concrete, brick and hard mirror wall.

Poor Ensemble- difficult to hear

In small to medium multipurpose hall for ensemble playing music, a similar communication problem arises for the musicians as well as the conductor. According to Helmut V. Fuchs, low frequency rumbling blurs the clarity of the music and makes it hard to hear the bass instruments which are curcial for ensemble play. However, as mutual hearing cannot really succeed under the poor room-acoustical conditions prevailing in hall, musician tend to play louder, to detriment of the overall performance, because they feel that they will otherwise not be able to hear themselves and control their playing.

Mechanical noise

There are a wide variety of building systems and equipment within or nearby a rehearsal room that can generate unwanted noise, creating distractions and also masking certain musical frequencies. Maximum permissible background noise levels should be related to the external ambient levels and to noise from air-conditioning plant and HVAC system. In certain situations where plant rooms are adjacent to noise-sensitive areas, maximum permissible noise levels at intake and extract louvres should be specified to limit this noise breaking back in through external skin, particularly at window.

Mechanical noise

Mechanical noise is the major problem of the acoustic problem in multipurpose hall. HVAC systems, fluorescent light fixture due to ballasts or transformers buzzing and air condition plant system. This nuisance cause all distraction, poor sound receive and disturbance to occupant inside the hall.

Impact

Poor communication

Poor acoustic conditions in these environments make it difficult to communicate. According to Michael Barron, a person speech will find it difficult to cope with the high noise levels which can lead to voice problems due to prolonged use of the voice and the need to shout to keep control. Echoes problem will find it difficult for person to talk each other because of disturbance sound from echoes. Low quality of communication will affect the comfort of person to talk each other.

Lost concentration

Poor acoustic condition effect the concentration of occupants for the event in the hall. Because of mechanical noise that comes from HVAC system; air-condition system and transformers buzzing of fluorescent light. Concentration of occupant will be disturbed and difficult to hear the speech by person in front of the hall. Helmut V. Fuchs says that adults and older children possess an ability to fill in missed or unintelligible words from a greater context.

Problem Statement

A multi-purpose hall is a large sized room wherein large number of people gathers to take part in a discussion or meeting, it presents various noise control and other acoustical challenges in front of us. What’s the major problem encountered in multi-purpose acoustics? Some of the major multi-purpose hall acoustics challenges that need to be fixed to ensure best quality sound are the major issue that gets reported about multi-purpose hall poor acoustics is related to lack of speech privacy. Multi-purpose halls which have poor sound insulation often face such acoustical issues and sensitive information can get leaked and inability of the listeners to hear the sound properly. A difficult goal is given that most modern halls are wide and have a low ceiling which favours sound arriving in the median plane of a forward-facing listener’s head (Ning Xiang, Gerhard Martin Sessler, 2014).

REFERENCES

J. Benesty, 2012, Advance In Network And Acoustic Echo Cancellation, Springer Science & Business Media, Berlin

Helmut V. Fuchs, 2013, Applied Acoustics: Concepts, Absorbers, and Silencers For Acoustical Comfort And Noise Control: Alternative Solutions - Innovative Tools - Practical Examples, Springer Science & Business Media, Berlin

David Littlefield, 2012, Metric Handbook Planning And Design Data 4th Edition, Architectural Press, Taylor And Francis New York

Michael Barron 2012, Auditorium Acoustics and Architectural Design, Spoon Press, New York

Ning Xiang & Gerhard Martin Sessler 2014, Acoustics, Information, and Communication: Memorial Volume in Honor of Manfred R. Schroeder, Spinger Cham Heildberg, New York