Why do some people like very loud
music? You know the kindyoure sitting at a stoplight
when you feel a strange rumbling. A car pulls up next to you.
All of your windows are closed, yet you can hear the music just
fine. In fact, its so loud, everything in your rear-view
mirror is vibrating to the beat!
Music affects our emotions. The notes, the instruments, the people
singing, and the words they sing. Not only that, but the volume
of the music affects us, too.
An article by David Clark in the spring 1995 issue of Professional
Sound has the following to say about loud sounds.
|"It turns out that loud sounds directly affect
our autonomic nervous system (also called involuntary--it
controls the body functions that you hope never stop, like
breathing and digestion), in a way similar to many stimulent
drugs. Adrenaline is released, the heart rate speeds up,
the guts tighten up and move. This is the rush you get from
loud music--it's real and it's beyond your conscious control.
Sounds addicting, doesnt it?"
As a sound engineer, you must resist the
urge to push the fader up "just one more notch."
You control the volume level the congregation is exposed
to. If you can hear it, it doesn't need to be any louder
Volume (or loudness) is actually the sound pressure level,
or SPL. Sound pressure levels are described using decibels.
In the next column is a listing of decibel levels of common
sounds and noises.
- threshold of hearing
very soft whisper at 1 ft.
soft whisper at 5 ft.
light traffic at 100 ft.
normal speech at 3 ft.
train whistle at 500 ft.
elevated train overhead
discomfort, boiler factory
nightclub dance music at 10 ft.
threshold of pain
one time may cause permanant hearing loss
sonic boom when plane is 1000 ft. overhead
||The decibel scale is based on a logarithmic
equation (similar to the Richter scale for measuring earthquakes).
If a sound source increases by 6dB, it has twice the SPL
(sound pressure level). For us to actually perceive a sound
to be twice as loud, it needs to be increased by 10dB. That
means that a 12dB increase is four times higher SPL, but
we perceive it only a little more than twice as loud.
The National Institute for Occupational Safety and Health (NIOSH) is part of the Centers for Disease Control in the United States federal department of Health and Human Services. They publish information regarding noise-induced hearing loss. Although aimed primarily at the construction industry, this information applies to any exposure of sound which can produce noise-induced hearing loss.
The chart below provides their maximum daily exposure figures.
|SPL in DbA
||Maximum Daily Exposure
- 8 hours
Here's a terrific chart from NIOSH (National Institute for Occupational Safety and Health) showing the relative levels of sound.
Many churches today not only reach sound levels of 100dBA or higher, some even STRIVE to reach such numbers - feeling this is what the congregation wants or needs. Other churches have implemented a decision on the maximum level allowed for normal services and events.
It's very easy to get caught up in the moment and keep pushing
those fader levels higher and higher. Exposure to loud sounds
breaks down your ears. They become less sensitive. When they become
less sensitive, you need a higher SPL to hear, so you turn up
the volume even higher.
God gave each of us only two ears. If we ruin them, we don't get
new ones. Take care of your ears and the ears of your congregational.
If you can hear it, it doesn't need to be any louder.
Suggestion: Use ear protection like ear muffs or plugs when using
power tools or when you're in a very noisy environment. Your ears
will thank you.