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Macro-Tech 5002VZ
Power Amplifier
Reference Manual
4 Operation
4.1 Precautions
The
Macro-Tech 5002VZ is protected from internal and
external faults, but you should still take the following
precautions for optimum performance and safety:
1. DANGER: The outputs can produce lethal en-
ergy levels! Do not change the output wiring
unless the amplifier has been off for at least
10 seconds.
2. DANGER: Improper use of this amplifier may
result in permanent hearing damage. Be very
careful when working near the loudspeakers
that are connected to this amplifier.
3. Improper wiring for Stereo, Bridge-Mono and
Parallel-Mono modes can result in serious oper-
ating difficulties. Refer to Section 3.3 for details.
4. WARNING: After the amplifier has been
turned off, wait at least 10 seconds before
changing the position of the stereo/mono
switch.
5. CAUTION: In Parallel-Mono mode, a jumper is
used between the positive (+) Channel 1 and
2 output terminals. Be sure to remove this
jumper for Stereo or Bridge-Mono mode, oth-
erwise high distortion and excessive heating
will occur.
Check the stereo/mono switch on the
back panel for proper position.
6. Turn off the amplifier and unplug it from the
AC power
before removing the
PIP card.
7. Use care when making connections, selecting
signal sources and controlling the output level.
The load you save may be your own.
8. Do not short the ground lead of an output cable
to the input signal ground. This may form a
ground loop and cause oscillations.
9. Operate the amplifier only at its rated AC power
voltage ±10% and the specified line frequency.
10. Never connect the output to a power supply
output, battery or power main.
Such connec-
tions may result in electrical shock.
11. Tampering with the circuitry or making unau-
thorized modifications can cause severe
electric shock and may invalidate the war-
ranty.
Remember: Crown is not liable for damage or personal
injury that results from overdriving system components.
4.2 Indicators
The
Macro-Tech 5002VZ has several internal indicators
that can be used to help to identify a problem that
causes a power supply to be put in “standby.” These
indicators are described in Section 4.3.2.
The amber
Enable indicator
is provided to show that
the amplifier has been turned on (or enabled), and that
its low-voltage power supply is working. It does not in-
dicate the status of the high-voltage power supplies.
The Enable indicator will stay on during unusual condi-
tions that cause the amplifier’s protection systems to
put a channel in “standby” (see Section 4.3).
The amber
ODEP indicators
confirm the normal op-
eration of Crown’s patented Output Device Emulation
Protection circuitry. During normal operation, they glow
brightly to show the presence of reserve thermal-
dynamic energy. An indicator will dim proportionally as
the energy reserve for its channel decreases. In the rare
event that a channel has no reserve energy, the indica-
tor turns off and
ODEP proportionally limits the channel’s
output drive level so the amplifier can continue safe op-
eration even when conditions are severe. (See Section
4.3.1 for a detailed description of
ODEP.)
The
ODEP indicator for the affected channel will turn off
if a high-voltage power supply is put in “standby” mode,
a high-voltage power supply fuse blows, or a trans-
former activates its thermal protection circuitry (see
Section 4.3). Both
ODEP indicators turn off if the ampli-
fier loses AC power, the power switch is turned off or
the low-voltage power supply fuse blows.
The green
Signal/
IOC indicators
show signal pres-
ence, distortion and input overload. As signal presence
indicators, they flash with normal intensity in sync with
the audio output. As
IOC (Input/Output Comparator) in-
dicators, they flash brightly if there is any difference be-
tween the input and output signal waveforms greater
than 0.05%. Because transient distortion happens
quickly, a 0.1 second “hold delay” keeps the indicators
on long enough to be easily noticed. The
IOC function
essentially provides
proof of distortion-free perfor-
mance. As input overload indicators, they flash brightly
Fig. 4.1 Indicators
