INTRODUCTION
The JF2000 is the first amplifier in the signature series line
of Hafler audio components. In the Hafler tradition, it is hand-
made in America. The signature series embodies Hafler's
philosophy of supplying the same quality music reproduc-
tion of higher priced audio components for less.
FEATURES
Output Section
High Current
Capability
Wide Load
Range
SOA
Protection
(Safe
Operating
Area)
Thermal
Protection
The JF2000 uses 32 MOSFET output devices - 16 per
channel - to source the high current and power required.
Each device is rated at 4.0 Amperes continuous drain
current at 100 degrees Celsius.
Each channel can safely produce peak transient output
currents exceeding 50 Amperes. This ensures that mo-
mentary speaker impedance dips and surge current require-
ments are easily supplied.
The JF2000 is fully rated for loads of 4 and 8 Ohms. It is
stable to 2 Ohms. (This means it will operate safely, cleanly
and stably into 2 Ohms, but very high power dissipation may
lead to frequent thermal shutdown.)
The 16 output devices per channel assure operation well
within the MOSFET Safe Operating Area with low imped-
ances and/or reactive loads.
The output devices of the JF2000 are protected by a so-
phisticated analog computing system. The device instanta-
neous temperature is continuously calculated by the com-
puter and compared to a maximum limit. If the limit is
reached, the computer cuts back thte power and lights the
channel’s distortion (red) front panel LED.
A pair of thermistors, one mounted on each heatsink, mea-
sure temperature of the output system. They control fan
speed and provide thermal shutdown in case temperatures
become too high for safe operation. (Thermal shutdown
turns the power lamp red.)
