Hafler p1000 Guida Utente

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POWER SWITCH
The POWER switch is located on the front panel of the amplifier. An internal lamp indicates when it is turned on.
Standard practice is to turn the amplifier on last and off first when switching components
individually to prevent sending damaging transients, generated in the source components, to the
speakers.
It is possible to leave the power switch in the on position and switch the amplifier remotely through a power
distribution block or preamp switched outlet. When doing so make sure the switch is rated for the current required
by the amplifier.
LEVEL CONTROLS
The input sensitivity, for each channel, can be adjusted individually using the level controls on the front panel.
The level controls on the P1000 are configured to allow each channel to be fully attenuated and are marked from
0 (minimum output) to 10 (full output).
In public systems where it is necessary to match levels, the knobs can be removed and the controls adjusted with
your fingers or a flathead screwdriver. Cover the holes with the enclosed plugs to restrict access.
INPUT CONFIGURATION SWITCHES
Balanced/Unbalanced
When the Balanced/Unbalanced switch position is in the Unbalanced position, the return (–) terminal is
connected to ground to prevent unstable amplifier operation when the RCA input jacks are used. When
using the XLR or 1/4" inputs, set the switch in the Balanced position. If the amplifier output is low, or has
excessive noise, make sure this switch is set to the correct position.
Normal/Bridged Mono
The amplifier operates in two-channel mode when the front panel NORMAL/BRIDGED MONO switch is
in the NORMAL position. To use the amplifier in single channel, bridged mono applications, the front
panel switch must be in the BRIDGED MONO position. When the switch is set in the BRIDGED MONO
position, the Channel 1 (+) and  (–) inputs are connected to Channel 2 in reversed polarity, which inverts
the Channel 2 output. Only the Channel 1 input is used, and the speaker is connected to the two positive
(+) output terminals. The amplifier gain is adjusted by the Channel 1 level control; the Channel 2 control
is not active.
Because of thermal considerations we do not recommend using less than a nominal eight ohm
load on the amplifier when running it in bridged mono.
GROUND SWITCH
Ground loops are characterized by a hum or buzz through the speakers and are caused by a voltage potential
difference between two points in a ground circuit. Ground loops are aggravated when multiple paths exist for a
given circuit. Mounting components in a rack with metal rails may introduce ground loops between associated
equipment, because the rails can establish an additional ground path.
The CHASSIS/FLOAT switch allows you to select the amplifier grounding scheme for best system compatibility.
With the switch in the CHASSIS position all signal grounds are referred to the chassis and power line ground.
In the FLOAT position the signal ground is decoupled from the chassis. The position of the switch is determined
by the overall noise in the system; choose the position which gives the lowest hum.
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