Tips; Search For Errors - VINCENT SA-31 Manuel D'utilisation

Burn in/ Warm up
Your audio components need a certain time
period until they reach maximum performance.
The duration of this "warm up" time is very diffe-
rent for the various elements of your audio system.
Higher and homogeneous sound quality is achie-
ved while keeping the device switched on.
Your audio specialist dealer has enough experi-
ence to give you more information.
Net frequency noise
Some audio source devices may in combination
with the amplifier cause a humming noise at
power line frequency audible from your speakers.
Usually, its volume varies with the volume setting
of the amplifier. This is no sign of a defect or fault
of your audio products but has to be eliminated.
Generally, every wall-powered device connected
to the ground wire of the power plug can cause
this problem when connected to the amplifier.
Experience shows that this problem is mainly cau-
sed by antenna-connected components (as TV-sets
or Tuners), personal computers, electrostatic loud-
speakers, subwoofers, record players or headpho-
28 Vincent

TIPS

ne amplifiers that are connected to the audio
inputs of the amplifier. Another possible reason for
humming noise is electromagnetic interference of
other components' power supplies with pick-up-
systems of record players (change the place of the
record player for a test).
In most electric devices the ground potentials of all
signals are connected to each other at one central
point, where they have one common connection.
If the device uses the protective conductor of the
wall outlet, the corresponding wire of the line cord
is connected intractably to the metal housing of
the device. This is mostly the point where the cen-
tral grounding point is attached to. By doing this
the housing is able to shield all signals from exter-
nal radiated noise. Some main amplifiers are
equipped with a "Ground Lift" switch. If it is acti-
vated, ground potential of the chassis and the pro-
tective ground wire are being separated from the
central signal ground point. The protective ground
wire keeps its function. Sometimes this helps pre-
vent noise caused by errors in grounding.
If the problem occurs and cannot be solved by
yourself your audio specialist dealer will help you.

SEARCH FOR ERRORS

Symptom Possible Cause
Mains cable is not connected to a suitable
Unit does not work
mains wall outlet.
after pressing the
power button
Mains cable has not been firmly inserted into
wall power socket and the device's socket.
Otherwise it may be defective.
Unit fuse or unit is defective.
The currently selected audio source (6) is
No sound on both
giving no signal.
channels although
the unit is ready for
One of the audio settings of a connected
use (POWER LED
DVD player (analogue/digital) has not been
is lit) correctly selected.
The output of the source device is not connec-
ted or is wrongly connected e.g. not connec-
ted to the selected input channel terminal of
the preamplifier.
Wrong input channel has been selected at the
preamplifier.
Volume (VOLUME) is set too low at the pre-
amplifier.
Main amplifier(s) has/have not been connec-
ted correctly to the preamplifier, is/are swit-
ched off or is/are faulty.
The speaker cables are not properly connec-
ted to the main amplifier's terminals or are
defective.
Countermeasure
Connect to a functioning socket using a suit-
able mains voltage.
Check the power cable. If necessary,
exchange it with a suitable mains cable and
push its plug firmly into wall socket and the
device's power connector.
Contact your dealer.
Switch on the source unit and begin play-
back.
Correct the settings in the player's setup.
Correct the connection.
Set the amplifier to the input that your desired
source is connected to (6).
Carefully increase the volume (8).
Check the connection and ready status of the
main amplifier(s) and whether it is/they are
working.
Check and tighten the speaker cables at the
main amplifier and the speakers.
Vincent 29