SIG
SIG (short for “signal present”) is the lowest step in the meters’ ladder. It senses the signal prior to the GAIN control, so when SIG is lit, you know the M•1400/M•1400i is receiving sig- nal. If it’s the only meter LED lit (meaning the other meter LEDs are not lit), the M•1400/ M•1400i is receiving a very weak signal (below
PROTECT
If the PROTECT LEDs are on, the M•1400/ M•1400i’s output section has shut down. That, of course, means you won’t hear anything until you rectify the situation. Three things can cause the PROTECT circuit to engage:
1.Powering up the M•1400/M•1400i. A built- in delay circuit saves your speakers (and ears) from the thumps or pops that can sometimes occur when powering up a system. During this 3 second delay, the PROTECT LEDs light up.
2.A short circuit (or near short) in either of
the outputs. Both the PROTECT and the SHORT LEDs light up.
3.The temperature in the M•1400/M•1400i has
risen to an unsafe level. The PROTECT and the TEMP STATUS HOT LEDs light up.
The M•1400/M•1400i
amp draws its ventilation
air in from the front and
out through the side pan- els. The amp needs plenty
of fresh air to stay cool. DO NOT BLOCK THE VENTILATION PORTS. See “Thermal Consid- erations” on page 23 for more details.
SHORT
If this LED comes on, the M•1400/M•1400i has detected a short circuit in either of the outputs, meaning that the hot (+) and cold
This
WARNING: The SHORT LEDs indicate an unsafe condition for the power amplifier. When the
Typical causes for a “short” indication would be either a shorted speaker cable or too many speaker cabinets connected to the amplifier (i.e., the load impedance is too low). If a “short” is indicated, please check your cables. If the cabling is OK, then reduce the number of cabinets driven by the amplifier.
Note: When using the amplifier in BRIDGE mode, one or both SHORT LEDs may light under shorted or low impedance conditions. Regardless of whether one or both LEDs light, it’s an indication of a problem that requires further investigation.
PROFESSIONAL POWER AMPLIFIER
ON
OFF
POWER
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