Hafler P3100, User Manual

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P3100™ Power Amplifier Hafler
Passion for Perfection
6
OPERATION
Power Switch
The POWER switch is located on the front panel of the amplifier. A front panel IDLE LED indicates when the amplifier is active.
Standard practice is to turn the amplifier on last and off first when switching components to prevent sending damaging transients to
the speakers.
There is a time-delayed “soft start” in the P3100 that mutes the sound for several seconds after startup. In the case of an entire
recording system being turned on at the same time with a power bar this should eliminate any loud thump. On turnoff, there is a sense
circuit that will mute the P3100 fairly quickly but when an entire system is shut off at the same time as from a power bar being turned
off, if any prior equipment thumps badly on turnoff, a small amount of this may pass through to the speakers. Therefore, in the case
of turning the system on or off with a power bar, the level controls should be turned to minimum before switching on and again just
before switching off.
Level Control
The input sensitivity for each channel can be adjusted individually using the level controls on the front panel. The gain control on an
amplifier is usually set fully clockwise to its maximum sensitivity. The level controls on the P3100 are not meant to be volume controls.
They are meant to be trim controls. That is, they are normally set to maximum level and are moved counter-clockwise to make
corrections for any imbalances in rooms that may not be symmetrical.
Short Circuit Protection
Due to the self-protecting properties of the output power MOSFETs, there is no need for sonically degrading voltage and current
limiting circuits. To protect the amplifier from problems which may occur in the speaker line the P3100 includes a FaultSafe™ overload
detection circuit. In the event of a short in the speaker load or cables, the speaker detection circuit will shut down that channel and light
the front panel FAULT indicator. If this happens, correct the fault and turn the amplifier off, then back on to reset.
LED Indicators
Amplifier operation is monitored via the front panel with four status LEDs as well as 9 meter LEDs for each channel. These indicators
can be used for system troubleshooting in case of aberrant behavior. The LEDS from the outermost to the centermost are:
Heat Indicates when the thermal protection circuit has shut down the amplifier. This occurs when the heatsink temperature
exceeds 90°C (194°F). This will also illuminate the FAULT LED. When the amplifier cools down below 80°C (176°F) the amplifier
will restart.
Fault Indicates when the output overload monitor detects a potentially damaging short and shuts down amplifier operation. This
also lights when the P3100 has a thermal shutdown or when driven too far into clipping for too long. After clearing the fault,
restore normal function by turning the amplifier off, then on again.
Idle Indicates the amplifier is powered on and the internal low voltage power supply is operating properly.
Meter LEDs Monitors the amplifier output and gives an approximate indication of amplifier power output.
Clip
These are the LEDs closest to the power switch. They light when the drive signal voltage exceeds the maximum for linear
operation of the output MOSFETs.
Warm Up
While the P3100 may be used with no ill effects whatsoever as soon as it comes out of muting, in order to achieve the best sonic
performance from the amplifier, we recommend letting it warm up for 1 hour before beginning any critical listening. The amplifier may
not deliver its full potential sound quality before this time has passed.
Cleaning and Maintenance
There is no requirement for regular maintenance on the electrical components of the amplifier. If the outer case becomes soiled, lightly
spraying a soft cloth with an ammonia-based cleaner should remove any grime. In the event of regular overheating, the P3100 should
be brought to a professional service technician for cleaning and testing of the internal components.