POWER AMPLIFIER
A great deal of mistakes in sound installa-
tions can be down to wrongly wired
audio connections. It is important that the
connections are correct to suit your system.
Unbalanced system
An unbalanced audio system is typically a
single conductor shielded with the centre
conductor relaying the signal and the shield
at ground.
Balanced system
Using a balanced audio system is where a
two conductor shielded cable has each
of the two centre conductors carrying the
signal but of opposite phase. This gives each
conductor an equal but inverted potential
difference from that of the ground.
It is recommend that you use balanced audo
connections if the unit before your amplifier
has a balanced output. This will eliminate such
as mains hum. For the best results xommon
grounding should be avoided. This means not
connecting the ground on both the amplifiers
input and output connectors. Wharfedale
pro advise that you connect the ground
(shield) of the input connecting cable to the
ground of the signal source while making
sure the ground (shield) is not connected to
the amplifier’s input connector. The output
cable connector from the amplifier if linking to
another amplifier (daisy chained via parallel
input sockets) should have the ground
(shield) connected. The input connector
ground (shield) to the following amplifier
should not be connected. This is the process
by which the ground (shield) is connected
(tied) at the source unit but is not connect
to the destination unit. If hum develops in
some instances the ground (shield) can be
connected on the input. Some manufacturers
have units that recommend that the input
connector ground (shield) is tied and the
output disconnected. In this instance you may
need to connect the input connector ground
(shield) going to the input of the wharfedale
pro unit. If an unbalanced system is used with
XLR connections please connect pin 3 to pin
1 (ground) of the connector. This will mean
that pin 2 transports the positive (+/hot) signal.
If pin 3 to pin 1 are not connected this results
in the negative (-/cold) input being ‘open’.
This will give an audible degradation of the
signal to noise ratio. This would relate to both
the input and output connectors and involve
the cable ground (shield) connected at both.
Please note that some manufacturers run
their units with pin 2 (-/cold) and pin 3 (+/hot).
This should be looked out for and then the
wiring could be modified with labeled cables
so that connections of +/hot go to their
corresp/hot etc. Some manufactures
run their units with balanced inputs and
unbalanced outputs, therefore care should
be taken with the connections when inserted
into the system.
Etensive Thermal Protection
All though the MP series of amplifier feature
powerful cooling fans it is possible that there
will be an abnormally high temperature
rise under some circumstances. When this
happens special sensors will cause the
amplifier to protect itself by first disconnecting
the loudspeakers and then by shutting down
the power supply until the temperature drops
to a more normal temperature. Normal
operation resumes automatically once the
amplifier cools down.
Output Short Circuit
The output lines can be accidentally shorted
together eigher by crossing the speaker wires
or because of defective loudspeakers. If the
short circuit remains in place then the thermal
protection system will eventually operate to
power down the complete amplifier.
BALANCED INPUT WIRING TO WHARFEDALE PRO UNIT WITH XLR CONNECTORS
BALANCED OUTPUT
INPUT to Wharfedale Pro unit
SIGNAL DIRECTION
Ground(earth) CABLE Only connect ground if hum occurs
BALANCED INPUT WIRING TO WHARFEDALE PRO UNIT WITH 1/4’’ JACK to XLR CONNECTORS
BALANCED OUTPUT
INPUT to Wharfedale Pro unit
SIGNAL DIRECTION
Ground(earth) CABLE Only connect ground if hum occurs
TIP
SLEEVE
RING
BALANCED INPUT WIRING TO WHARFEDALE PRO UNIT WITH STEREO 1/4’’ JACK to XLR CONNECTORS
BALANCED OUTPUT
INPUT to Wharfedale Pro unit
SIGNAL DIRECTION
Ground(earth) CABLE Only connect ground if hum occurs
TIP
SLEEVE
RING
RING
TIP
BALANCED INPUT WIRING TO WHARFEDALE PRO UNIT WITH XLR CONNECTORS to STEREO 1/4’’ JACK
BALANCED OUTPUT
INPUT to
Wharfedale Pro unit
SIGNAL DIRECTION
Ground(earth) CABLE Only connect ground if hum occurs
SLEEVE
TIP
RING
UNBALANCED INPUT AND OUTPUT WIRING WITH MONO 1/4’’ JACK CONNECTIONS
OUTPUT
INPUT to Wharfedale Pro unit
SIGNAL DIRECTION
INPUT
TIP
Ground(earth) CABLE
SLEEVE
TIP
SLEEVE
BALANCED OUTPUT WIRING FROM WHARFEDALE PRO UNIT WITH XLR CONNECTORS TO BALANCED UNIT
OUTPUT from wharfedale Pro unit
SIGNAL DIRECTION
BALANCED INPUT
Ground(earth) CABLE Only connect ground if hum occurs
SLEEVE
SIGNAL DIRECTION
OUTPUT to Wharfedale Pro unit
