|
|
Why do some people like very loud
music? You know the kind–you’re 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, it’s 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, doesn’t 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. |
| dB |
|
- 0
- 10
- 20
- 30
- 40
- 50
- 60
- 70
- 80
- 90
- 100
- 110
- 120
- 130
- 140
- 145
- 170
- 200
|
- threshold of hearing
rustling leaves
very soft whisper at 1 ft.
soft whisper at 5 ft.
normal house
light traffic at 100 ft.
normal speech at 3 ft.
hair drier
noisy restaurant
train whistle at 500 ft.
elevated train overhead
discomfort, boiler factory
nightclub dance music at 10 ft.
threshold of pain
firecracker
one time may cause permanant hearing loss
jet engine
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. |
OSHA (Occupational Safety and Health Administration) has laws
regarding sound level exposure times for people working in loud
or noisy environments for extended periods of time.
| SPL in DbA |
Maximum daily exposure in hours |
|
- 90
- 95
- 100
- 105
- 110
- 115
|
- 8
- 4
- 2
- 1
- .5
- .25 or less
-
OSHA 2206 (1978) |
 |
|
|
|
Don't think your church reaches such high SPL levels? Think again--in
his book, "Why are Church Sound Systems and Church Acoustics
so Confusing?" Joseph DeBuglio states the following:
"The average sound pressure level of congregational singing
in a conservative Protestant church is about 95 decibels (dB)
and in a Pentecostal type church the singing is about 5 to 10
dB louder."
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.
|
