Hafler p1000 Guida Utente
NOMAD (NOn-Multiplying Advanced Decision, patent pending) SAFE AREA PROTECTION
The output MOSFETs have an upper limit on the power, current, or voltage they can withstand without being
damaged. The operating range within these limits is called the Safe Operating Area.
The output MOSFETs have an upper limit on the power, current, or voltage they can withstand without being
damaged. The operating range within these limits is called the Safe Operating Area.
Traditional amplifier designs use sensing circuits to measure the device voltage and current and a multiplying
circuit to determine whether the dissipation (power) is within the Safe Operating Area. Limiter circuits are then
activated to prevent exceeding the device ratings. This multiplication method has numerous problems,
including temperature sensitivity, nonlinearity and complexity.
circuit to determine whether the dissipation (power) is within the Safe Operating Area. Limiter circuits are then
activated to prevent exceeding the device ratings. This multiplication method has numerous problems,
including temperature sensitivity, nonlinearity and complexity.
The NOMAD circuit, used in the P1000, avoids these problems by deriving the device dissipation by a different
method. Sensing circuits measure the device voltage and current. NOMAD determines the allowed current after
an established duration. A clamping transistor is activated to limit the gate voltage.
method. Sensing circuits measure the device voltage and current. NOMAD determines the allowed current after
an established duration. A clamping transistor is activated to limit the gate voltage.
LED INDICATORS
Amplifier operation is monitored internally and each channel has three status LEDs. These indicators can be
used for system troubleshooting in case of aberrant behavior.
Amplifier operation is monitored internally and each channel has three status LEDs. These indicators can be
used for system troubleshooting in case of aberrant behavior.
Signal
Monitors the amplifier output and lights when a signal is present. The SIGNAL indicator is calibrated
to activate at an equivalent input voltage of 30mV, with the amplifier set for full gain.
Monitors the amplifier output and lights when a signal is present. The SIGNAL indicator is calibrated
to activate at an equivalent input voltage of 30mV, with the amplifier set for full gain.
Clipping
Monitors the DRIVE SIGNAL and lights when the drive signal voltage exceeds the maximum level for
linear operation of the output MOSFETs.
Monitors the DRIVE SIGNAL and lights when the drive signal voltage exceeds the maximum level for
linear operation of the output MOSFETs.
Thermal
Indicates when the thermal protection has shut down the amplifier. This occurs when the heatsink
temperature becomes excessive.
Indicates when the thermal protection has shut down the amplifier. This occurs when the heatsink
temperature becomes excessive.
WARM UP
In order to achieve the best sonic performance and image stability from the amplifier, we recommend letting
it warm up for 1 hour before beginning any critical listening.
In order to achieve the best sonic performance and image stability from the amplifier, we recommend letting
it warm up for 1 hour before beginning any critical listening.
CLEANING AND MAINTENANCE
There is no requirement for regular maintenance on the electronic components of the amplifier. If the case
becomes soiled it can be cleaned using a soft cloth and a mild detergent, such as spray window or glass cleaner.
If the amplifier is located in a particularly dusty environment, cleaning the inside with compressed air or
vacuuming every 18 to 24 months is sufficient.
There is no requirement for regular maintenance on the electronic components of the amplifier. If the case
becomes soiled it can be cleaned using a soft cloth and a mild detergent, such as spray window or glass cleaner.
If the amplifier is located in a particularly dusty environment, cleaning the inside with compressed air or
vacuuming every 18 to 24 months is sufficient.
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