Information On Hearing Loss; Start-Up; Connections - Omnitronic AZ-212A User Manual

If hired persons work with amplification systems: the noise levels of music events are almost always too high.
This is why the entrepreneur has to set up warning signs and provide hearing protectors. The staff has to
use these.
Please note: OMNITRONIC cannot be made liable for damages caused by incorrect installations and
excessive noise levels!

Information on hearing loss

More and more young people suffer from hearing loss of 25 decibel or more, mainly caused by loud music
from portable cassette recorders and CD players or discotheques.
Everybody operating amplification systems should know to what sound pressure levels he exposes his or the
audience's hearing. As an average levels between 75 and 105 dB(A) in the discotheque or 95 and 115 dB(A)
at a rock concert are reached. Individual peaks can exceed the pain level at 130 dB(A). Such levels are
typical for motor chainsaws or jack hammers.
10 dB Heartbeat
20 - 30 dB Whisper
40 dB Average home
50 dB Light traffic
60 dB Normal conversation
70 dB Vacuum cleaner
It is important to know that doubling the power increases the noise level by 3 dB. The human hearing does
only recognizes a doubling of the sound level when the noise level is increased by 10 dB. Damaging the
hearing does not depend on the sound level but on the noise level and starts way before the pain level.
Many people deceive themselves by thinking that noise is something they can get accustomed to. It is
possible that a positive opinion of a certain noise can reduce the physiological reaction, but the slow impacts
on the inner hearing must not be neglected: over stimulation and continuous elimination of the Cortic organ's
hair cells.
The reason why some people have got accustomed to a certain noise level and are no longer disturbed is
that they have already suffered a hearing damage. This damage make the insensitive to those frequencies
forming the loudest part of the noise. Getting accustomed to noise does not mean anything other than trying
to get along with the hearing loss in everyday life. The hearing loss itself cannot be healed, it can only be
compensated by hearing aids.
Subjectively, the hearing loss feels like dampened ears. This effect weakens with the time, but a loss in
hearing sensitivity often remains.
In order to relax the hearing sufficiently, the noise level should not exceed 70 dB(A) for 10 hours. Higher
noise levels during this relaxing period can prevent the relaxation and promote a permanent hearing damage
(Tinitus) or hearing loss.
Therefore: Whoever wants to maintain his hearing should use hearing protectors!

START-UP

This speaker-system is directly connected with the audio mixer.
Make sure that the power switch is set to "OFF". Before you connect the devices, all units have to be
switched off and the master-control is set to "0".

Connections

A good cable run improves the sound quality remarkably. Input cables should be short and direct, since high
frequencies will mostly be absorbed if the cables are unnecessarily long. Besides that a longer cable may
lead to humming and noise trouble. If long cable runs are unavoidable, you should use balanced cables.
Overview on the different noise levels
80 dB Heavy traffic or telephone ringing
90 dB Pneumatic drill
100 dB Power mower
120 dB Boom box in car
130 dB Pain level
140 dB Jet plane 30 meters overhead
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