Omnitronic 10452460, User Manual

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00030074.DOC, Version 1_0 30/32
If you want to switch off the system, switch off the amplifier first and then the pre-amplifiers in order to avoid
acoustic shocks on the speakers.
8.3 Indicators
All important operating modes of the amplifier are arranged on the front panel.
SIGNAL input signal
CLIP short-circuit or incorrect impedance or signal distorted
PROTECT active during stabilisation period after switching on or when one of the
protective circuits started
BRIDGE bridge operation selected
ON power indicator
8.4 Adjusting the level
After having set the volume controls of the pre-amplifier in null-position, turn the gain controls of your
amplifier to mid-position. You must not hear any loud humming. If there is humming nevertheless, check the
connecting cables between the pre-amplifier and the amplifier (switch off components before). Now adjust
the volume with the gain controls.
Caution! Increase the level of each channel only so far that the CLIP-LED lights up shortly. Thus, you avoid
that the output signal is distorted and your speakers are damaged.
In bridge operation of channel CH1 and CH2 turn the level control CH2 to zero and adjust the volume with
the control of CH1 only. In bridge operation of channel CH3 and CH4 turn the level control CH4 to zero and
adjust the volume with the control of CH3 only.
When operating the amplifying system, please make sure that the loudspeakers always sound well. When
distortions can be heard, either the amplifier or the loudspeaker is overloaded. Overloads can quickly lead to
amplifier or speaker damage.
In order to avoid damage, please reduce the volume immediately when distortions can be heard. When
speaker-systems are destroyed by overload, the guarantee becomes void.
Always check the sound pressure level with a meter in order to keep to the threshold.
8.5 Protective circuits
The protective circuits prevent damage to the speakers and the amplifier. If activated, the speakers are
electrically separated from the amplifier and the PROTECT LED lights up:
1. for approx. 3 seconds during the stabilisation period after switching on
2. in case of a short-circuit at a speaker output
3. in case of overheating of one of the channels
4. in case of a DC voltage at a speaker output
5. in case of a VHF signal at a speaker output
If one of the PROTECT LEDs lights up red during operation or if it does not extinguish after switching on, the
amplifier has to be switched off and the cause of the fault has to be removed.