14
CH
2
SPEAKER OUTPUTS
+
–
–
+
+
–
CH
1
120 VAC 60 Hz
1500 WATTS
(MONO BRIDGE)
1400 WATTS
4 OHM LOAD MIN.
700 WATTS CH
2 OHM LOAD MIN.
CONCEIVED, DESIGNED, AND MANUFACTURED BY MACKIE DESIGNS INC • WOODINVILLE • WA • 98072 • USA • MADE IN USA • FABRIQUE AU USA • PATENTS PENDING
COPYRIGHT
©
1997 • THE FOLLOWING ARE TRADEMARKS AND/OR REGISTERED TRADEMARKS OF MACKIE DESIGN INC.: "MACKIE", FR SERIES, AND THE "RUNNING MAN" FIG
MONO
BRIDGE
SERIAL NUMBER
MANUFACTURING DATE
RISK OF ELECTRIC SHOCK
DO NOT OPEN
REPLACE WITH THE SAME TYPE FUSE AND RATING.
DISCONNECT SUPPLY CORD BEFORE CHANGING FUSE
UTILISE UN FUSIBLE DE RECHANGE DE MÊME TYPE.
DEBRANCHER AVANT DE REMPLACER LE FUSIBLE
WARNING:
TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT
EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. DO NOT REMOVE COVER.
NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL.
CAUTION
AVIS:
RISQUE DE CHOC ELECTRIQUE — NE PAS OUVRIR
TEMP STATUS
TEMP
(short for temperature) is another
feature designed to keep your mind at ease.
Normally the
COLD
LED is lit, indicating that
the M•1400i is working normally. Under ex-
treme conditions the amplifier may overheat.
You may ask, “What kind of extreme condi-
tions?”
Overheating problems are usually caused by
one of the following situations: improper venti-
lation, high ambient temperatures, overdriving
the amplifier into clipping, driving the ampli-
fier hard into low impedance loads, frayed or
partially shorted speaker cables, or defective
or internally shorted speakers.
The heaviest load the M•1400i can tolerate
is 2 ohms per channel (4 ohms in bridged
mode). If you’ve got a set of speakers wired in
parallel, be sure the load isn’t adding up to less
than 2 ohms. Anything below 2 ohms can cause
the
SHORT
LED to light and trigger the
PROTECT
mode.
Remember:
As the load gets
“heavier,” its value in ohms
goes down. For instance, a
2-ohm speaker load is twice
as “heavy” as a 4-ohm load.
Please see
“Do The Math: Ohms, Loads and
Such” in
Appendix E
to learn about speaker
loads.
As the internal temperature of the amplifier
rises, the fan kicks into high speed. This occurs
at 60
°
C (140
°
F). More air moves through the
constant temperature gradient cooling tunnel
to remove additional heat from the output
transistors. However, if the internal tempera-
ture of the amplifier should exceed 80
°
C
(176
°
F), the
COLD
LED turns off, the
HOT
LED turns on, and both
PROTECT
LEDs shine.
The output of the amplifier is muted — at this
point the amplifier is in Standby mode and
remains there until the internal temperature
cools off to a safe level (55
°
C or 131
°
F). When
this occurs, the
HOT
LED and
PROTECT
LEDs
turn off, the
COLD
LED turns on and normal
operation resumes.
Be Aware:
If the
HOT
LED
comes on frequently, some-
thing is overworking the
M•1400i or it’s not properly
ventilated. Look at each of
the “extreme conditions” described above and
try to determine what is causing the amplifier
to overheat. Refer to “Thermal Considerations”
on page 23 or to the “Troubleshooting” section
in
Appendix A
for more help.
What’s that? Why doesn’t the
fan just go fast all the time?
Well, if it did, you might actu-
ally hear it whirring during
your quiet moments (there
are quiet moments in your life, aren’t there?).
While this whirring would be of no concern in
most live-sound situations, it could become
annoying in a control room environment. So,
when the M•1400i is not working hard, the fan
goes slow; when the music gets loud and puts
the amp to work, the fan goes fast.
POWER
To make the amp operate, push the top half
of the
POWER
switch. It clicks into place and a
soothing green light adjacent to it glows. To
turn the amp off, push the lower half. It’ll click
again and the green light will extinguish.
M•1200 Rear Panel
