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Compact Amplifier: The Kenwood KAC-M1804 compact Class D
4-channel amplifier is designed to boost the output and clarity of your car
stereo. The amp features a conformal coating on the circuit board to protect it
from moisture. This allows you to use the amp for marine applications, or on
All-Terrain Vehicles (ATVs). The KAC-M1804 delivers 45 watts RMS x 4 channels at
4 ohms. It cannot be bridged or operated at impedances less than 4 ohms.
Protection Circuitry: The amplifier features protection
circuitry for thermal overload, DC offset, and short circuits. The amp stops
operating when it goes into protection mode. (There are no LED indicators.)
Signal-sensing Turn-on: When the amplifier is connected to a
factory head unit, or an aftermarket unit without preamp outputs, you can cut
off the amp's RCA input connectors and splice the head unit's speaker wires to
the input wires. In this case, the amplifier's Signal-sensing Turn-on feature
will turn on the amp when a signal is detected on the input. This eliminates the
need to connect a turn-on lead to the amp's Power Control (blue) wire.
No Controls or Crossovers: The KAC-M1804 does not have
built-in crossovers or controls. If you are connecting the amp to small
speakers, it is recommended that you use the crossovers built into the connected
head unit, or use
bass blockers on the speaker outputs.
Amp Wiring: The Kenwood KAC-M1804 is equipped with a 22-pin
DC connector on the amplifier. The included 5' DC harness, which plugs into the
connector, has wires for +12V battery power, ground, power control (turn-on
lead), and four speakers.
Power/Ground: The +12V Power and Ground wires are 16 AWG
wires. The power wire can be connected to the car's fuse box or directly to the
battery. The amp is protected by a 15A ATM mini blade fuse. If wiring directly
to the battery, you can use a 10 AWG wire with an in-line 15A fuse installed no more than
18" from the battery terminal. The ground wire should be attached to a
metal area close to the amplifier.
Power Control: The blue Power Control wire should be
connected to the head unit's remote turn-on lead when an aftermarket unit is
used. This wire does not need to be connected if you're using speaker level
inputs. The Signal-sensing Turn-on feature will turn on the amplifier when an
input signal is detected.
Line-Level Inputs: The amplifier is equipped with two pairs
of RCA inputs on 7-1/2" pigtails for connecting stereo RCA patch cables from the
head unit to the amp. Two 38" stereo RCA patch cables are included. If using a
factory head unit, or a unit without preamp outputs, you can cut off the RCA
jacks and splice the four speaker wires to the two inputs, maintaining the same
Speaker Outputs: The included DC harness has eight wires for connecting
four speakers to the amp: Front left (white + white/black), Front right (gray +
gray/black), Rear left (green + green/black), and Rear right (purple +
purple/black). The amp is not capable of bridging or connecting to speakers with
impedances less than 4 ohms.