Operation; Switching On/Off; Input Level Adjustment; Adjusting The Level - PSSO QDA-4400 Bedienungsanleitung

6 6 6 6 Operation

6.1 Switching on/off

To prevent loud switching noise, always switch on all other units of the amplifier system before switching on the power
amplifier. After operation, switch off the power amplifier first. Prior to switching on set all level controls to the left stop
position and make sure that the operating mode selector switch MODE is set to the correct position.
Switch on the amplifier with the power switch. The PROTECT indicators light up for about 10 seconds. If they do not,
check if the amplifier is connected to the mains correctly. After the turn-on delay the speakers are activated (PROTECT
indicators are off). Afterwards the power indicator ON lights up and indicates that the amplifier is switched on.

6.2 Input level adjustment

With the SENSITIVITY the input sensitivity of the amplifier can be matched to the output level of the preceding unit.

6.3 Adjusting the level

First, set the volume controls of the preamplifiers to zero and turn the level controls of the amplifier to mid-position. There
should be no loud humming. Should humming persist, check the connection cables between the preamplifier and the
amplifier (switch off components before).
Adjust the level controls to the desired volume value. The LEDs "-5 dB", "-10 dB" and "-20 dB" show the adjusted input
level. In case of overload, the red CLIP indicator lights up. In this case, reduce the volume correspondingly.
In bridge mode the level controls for channel 2 and channel 4 are disabled. Volume adjustment is made with the level
control for channel 1 and channel 4.

6.4 Protective circuits

The integrated protective circuits prevent damage to the speakers and the amplifier. If activated, the speakers are
electrically separated from the amplifier and the PROTECT indicator lights up. If the indicator lights up 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.
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7 7 7 7 Problem Chart

Problem
No power.
No sound.
Fans do not work, LEDs do not light
up.
PROTECT LED lights up permanently.
Cause
The power cord is not connected.
•
The power cord of the respective
•
device is not connected properly or
not connected at all.
The connection socket or the plug is
•
dirty.
The power cord is not connected.
•
Amplifier is overheated due to
•
impurities.
Impedance of speakers too low.
•
Short-circuit in speaker connection
•
or in speakers.
Technical default of amplifier.
•
Remedy
Check the power cord and any
•
extension cables.
Check the power cord and if the
•
plugs are tightly connected with the
sockets.
Clean the socket and/or the plug.
•
Please check if the power is
•
available
Clean the fan grille.
•
Connect other speakers.
•
Check speakers.
•
Switch amplifier off and have the
•
device checked by a service
technician.
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