Noise Absorption and Acoustic Problems with Noise within Houses of Worship
Houses of Worship acoustics require special attention and knowledge to the nuances of voluminous spaces, hard surfaces, especially in the new architectural designs of today’s buildings. This excessive space is wonderfully impressive but allows for significant reverberation, which we are familiar with as echoes. Reverberation can reduce speech legibility and can make otherwise good church sound systems sound awkward. Imagine your ear being bombarded with an array of sounds at different decibels repeatedly served in waves. These sound waves maintain a surprising amount of energy and continue on absorbing and interfering with other sound waves. This is overwhelming for our ears and the echoes and spoken word dilutes more and more with each wave. This reverberation problem and acoustics and noise control in general are quite complex in nature and more often than not require expert knowledge to solve such problems.
There is a difference between typical noise control such as industrial noise, construction noise, commercial / retail noise and ‘church acoustics’. Simply absorbing excess sound, as done in many commercial and industrial applications, is not the best approach for church acoustics. Noise control solutions ideally need to be configured by professional noise control specialists to balance noise absorption, noise reflection, noise barrier products and all while delivering them in a finished aesthetically pleasing result. The vast reflective wall areas within houses of worship benefit from being broken up with interesting acoustic materials and/or colors and often the vaulted ceilings require elaborate baffle systems. Floors, as well as walls and ceilings, during construction of new buildings will benefit from an entire line of specialized acoustic materials such as mass loaded vinyl barrier material or ceiling tiles & barriers used beneath the visible surface; within the construction material (i.e. studs, sub flooring etc)
To help better understand you need to move beyond the materials to the sound itself. When speaking of sounds, most people think of the vibrations in any type of medium, which can cause the sensation of hearing. Any unwanted sound is perceived as a noise. The term is definitely subjective, since what is music for one person can very well be noise for another. When such unwanted sounds are excessive, their effects can be destructive, which is known by the name of noise pollution. Noise pollution or noise levels are rated by what we know as decibels. Decibel (Db) is the volume of noise emitted from the originating source. You’ll see “db” next to all types of products such as printers, power tools, appliances and others to great to list. This is the rated noise level of the originator of the noise/sound. Little known is the impact that noise does indeed have on our communities and lives. Adverse noise effects fall into three categories, physiological, psychological and communicational. Unfortunately, there aren’t any known and adopted remedies for the last two categories. Noise pollution is a complex problem and surveys show a disturbing fact, that noise levels are continually rising in cities. This gives us many positive reasons to focus on improving noise quality in other aspects of our life. Such as home, worship buildings and work.
As far as the sounds inside buildings go, we can speak about two main ways of transmission. It may be quite surprising how sound does travel through buildings and environments.
Firstly, the sound emanated from either human activity or mechanical noise inside the building travels airborne against and through walls, ceiling or floor. This is obvious and actually slightly more difficult to control. However acoustic wall, ceiling and floor treatments will help absorb the excess sound energy and help filter out and control the noise. Hanging baffles from ceilings, often seen in the likes of gymnasiums, are an excellent way to absorb the array of excess sound waves causing the echo and reverberation problems.
Secondly, interior sound can be transmitted not through air, but through the building itself. The former is easier to abate than the latter through wall or ceiling assemblies which meet certain established performance standards.
For example most of us are familiar with ceiling grids, the ceiling tiles in grids you see in retail, doctor’s offices, class room areas of schools and churches. Well those grids are suspended simply by metal wires. Sounds hit the ceiling and grids and their vibrations travel up through the ceiling to the floor above creating noise. Through walls sound actually travels through metal objects such as nails, screws and such. Sound travels effortlessly through all types of materials, electrical wiring, support framing and especially gaps, such as electrical sockets, doors, windows etc. Now many sounds from human activity include loud voice or amplified systems to reach their intended recipients clearer; however this often increases reverberation and echo amplifying the problem. Mechanical noise refers to the sounds produced by elevators, generators, air conditioning systems and so on. The sheer sizes of some churches require incredibly large HVAC (Heating and Air Conditioning Units) to keep rooms comfortable and temperature controlled. These mounted on roofs often require special know how and materials to reduce the noise and just as important, vibration from these types of mechanical equipments.
To complicate some problems further churches are communal places that act as multipurpose spaces for large gatherings and events as well as venues for smaller groups and classroom activities. This variation of spaces does require attention when dealing with church acoustics; the contents, size, space and materials in those spaces require acknowledgement to all of the elements present which need to be considered. Not only in regards to the spoken word either, but in regards to the mechanical elements running the building itself. As with many sound issues some solutions do compound the problems when not used correctly. For example, an amplification system that is installed to improve volume so words can reach the audience throughout and this often compounds the problem. Now the excess sound waves are louder and reflect off of more areas causing greater distortion and echoes. Treating the noise at all its levels is one of the subtleties that are addressed when specialists consult on products needed for noise reduction and improvement of acoustics.
However, many contractors installing these systems may not realize that reverberation time ideal for music can make the spoken word difficult to understand. The structural differences of these spaces (cathedrals, class rooms, multi-purpose, private rooms) and their contents make custom acoustic solutions for your project necessary, not to mention the aesthetics in the typical House of Worship. The materials, volume of space, variety of speech and sounds are all contributing factors in making a positive experience with improved interest, attention spans and even less fatigue. When all the types of noises, building surfaces and understanding of all mitigating factors are observed and understood the end result will be harmonious.
Noise Absorption and Acoustic Problems with Noise within Houses of Worship