User manual

00030025.DOC, Version 1.1
20/28
Overview on the different noise levels
10 dB Heartbeat
20 - 30 dB Whisper
40 dB Average home
50 dB Light traffic
60 dB Normal conversation
7
0 dB Vacuum cleaner
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
It is important to know that doubling the power increases the noise level by 3 dB. The human hearing does
only recognize a doubling of the sound level when the noise level is increasey by 10 dB. Damaging the
hearing does not depend on the sound level but on the noise level and starts way befor 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 unsensitive to those frequencies
forming the loudest part of the noise. Getting accustomed to noise does not mean anything oter 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!
5. INSTALLATION
Install the device on a solid, plane, anti-slip, vibration-free, oscilation-free and fire-resistant surface.
Make sure that the power switch is set to OFF. Before you connect the devices, all units have to be switched
off.
5.1 Inputs
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.
In order to obtain highest sound quality, only use high-quality cables for
connecting the devices. Make sure that the cables are properly fixed.
At the mono input channels, the microphone signals are connected via the
XLR-sockets, the line-signals via the jack sockets.
Please note: you must only connect one kind of signal to a mono channel –
either mic or line.