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KAC-7251
KAC-7201
© PRINTED IN CHINA B64-2569-00/00 (KV/EV)
POWER AMPLIFIER
7 page 2-13
INSTRUCTION MANUAL
AMPLIFICATEUR DE PUISSANCE
7 page 14-25
MODE D'EMPLOI
AMPLIFICADOR DE POTENCIA
7 página 26-37
MANUAL DE INSTRUCCIONES
Take the time to read through this instruction manual.
Familiarity with installation and operation procedures will help
you obtain the best performance from your new power amplifier.
For your records
Record the serial number, found on the back of the unit, in the spaces
designated on the warranty card, and in the space provided below.
Refer to the model and serial numbers whenever you call upon your
KENWOOD dealer for information or service on the product.
Model KAC-7251/7201 Serial number
KAC-7251/7201(KE) 1English
02.11.14
10:30 AM
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2 English
Safety precautions
To prevent injury or fire, take the following
precautions:
·When extending the ignition, battery, or
ground wires, make sure to use automotive-
grade wires or other wires with a 5 mm2
(AWG 10) or more to prevent wire
deterioration and damage to the wire coating.
· To prevent a short circuit, never put or leave
any metallic objects (such as coins or metal
tools) inside the unit.
· If the unit starts to emit smoke or strange
smells, turn off the power immediately and
consult your Kenwood dealer.
· Do not touch the unit during use because the
surface of the unit becomes hot and may
cause burns if touched.
To prevent damage to the machine, take the
following precautions:
· Be sure the unit is connected to a 12V DC
power supply with a negative ground
connection.
· Do not open the top or bottom covers of the
unit.
· Do not install the unit in a spot exposed to
direct sunlight or excessive heat or humidity.
Also avoid places with too much dust or the
possibility of water splashing.
· When replacing a fuse, only use a new one
with the prescribed rating. Using a fuse with
the wrong rating may cause your unit to
malfunction.
· To prevent a short circuit when replacing a
fuse, first disconnect the wiring harness.
· If you experience problems during
installation, consult your Kenwood dealer.
· If the unit does not seem to be working right,
consult your Kenwood dealer.
FCC WARNING
This equipment may generate or use radio
frequency energy. Changes or modifications
to this equipment may cause harmful
interference unless the modifications are
expressly approved in the instruction manual.
The user could lose the authority to operate
this equipment if an unauthorized change or
modification is made.
Cleaning the unit
If the front panel gets dirty, turn off the power
and wipe the panel with a dry silicon cloth or
soft cloth.
Do not wipe the panel with a hard cloth or a
cloth dampened by volatile solvents such as
paint thinner and alcohol. They can scratch the
surface of the panel and/or cause the indicator
letters to peel off.
To prevent battery rise
When the unit is used in the ACC ON position
without turning the engine ON, it depletes the
battery. Use it after starting the engine.
Protection function
There is a Protection function installed in the
unit to protect the unit and speakers from
various problems. When Protection operates,
the indicator informs you of the condition.
(Refer to page 5)
Accessories
2CAUTION
NOTE
2CAUTION
2WARNING
Part name
Number of
Items
External
View
Self-tapping screws
(ø4 × 16 mm)
4
Terminal cover
(Power terminal)
1
Speaker level input
cable
1
Part name
Number of
Items
External
View
Remote cable
1
Remote controler
1
Knob
1
Dressing plate
1
OFF
+6 dB
+12
+9
Nut
1
Washer
1
Self-tapping screws
(ø3 × 12 mm)
2
Double-side tape
1
(KAC-7251 only)
KAC-7251/7201(KE) 1English
02.11.14
10:30 AM
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English
3
Installation
· Do not install in the below locations;
(Unstable location, In a location that interferes with driving, In a location that gets wet, In a
dusty location, In a place that gets hot, In a place that gets direct sunlight, In a location that
gets hit by hot air)
· Do not install the unit under the carpet. Otherwise heat build-up occurs and the unit may be
damaged.
· Install this unit in a location which allows heat to easily dissipate.
Once installed, do not place any object on top of the unit.
· The surface temperature of the amplifier will become hot during use. Install the amplifier in a
place where people, resins, and other substances that are sensitive to heat will not come into
contact with it.
· This unit has cooling fans to decrease the internal temperature. Be careful not to block the
cooling fan openings when installing the unit. Blocking these openings will inhibit the cooling of
the internal temperature and result in malfunction.
· When making a hole under a seat, inside the trunk, or somewhere else in the vehicle, check
that there is nothing hazardous on the opposite side such as a gasoline tank, brake pipe, or
wiring harness, and be careful not to cause scratches or other damage.
· Do not install near the dashboard, rear tray, or air bag safety parts.
· The installation to the vehicle should securely fasten the unit to a place in which it will not
obstruct driving. If the unit comes off due to a shock and hits a person or safety part, it may
cause injury or an accident.
· After installing the unit, check to make sure that electrical equipment such as the brake lamps,
turn signal lamps and windshield wipers operate normally.
2CAUTION
Installation board, etc.
(thickness : 15 mm or more)
Self-tapping screw
(ø4 × 16 mm)
Cooling fan
Remote cable
OFF
+6
dB
+12
+9
Remote controler
Dressing plate
Nut
Knob
Self-tapping screw
(ø3 × 12 mm)
Remote controler (KAC-7251 only)
Double-side tape
Washer
Mount the Dressing plate
according to the mount
angle of the Remote
Controller.
Fully rotate the knob
counterclockwise (CCW), and adjust the
marking of the knob to the "OFF" position of
the Dressing plate.
NOTE
OFF
+6
dB
+12
+9
KAC-7251/7201(KE) 1English
02.11.14
10:30 AM
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4 English
Controls / Indicator
12
3
45
(W)
20
40
10
1 LPF FREQUENCY control
Sets the cutoff frequency when the FILTER
switch is set to LPF.
2 FILTER switch
This switch allows to apply high-pass or
low-pass filtering to the speaker outputs.
· HPF (High-Pass Filter) position:
Only frequencies of 150 Hz or higher are
output. (Frequencies below 150 Hz are cut.)
· OFF position:
The entire bandwidth is output without
filtering.
· LPF (Low-Pass Filter) position:
The filter outputs the band of lower
frequencies than the frequency set with the
LPF FREQUENCY control.
The speaker output is automatically
switched to monaural (L+R).
3 BASS BOOST switch
Sets the boost level for bass control.
· 12dB position:
BASS BOOST is +12 dB.
· KAC-7201: OFF position:
BASS BOOST is OFF.
· KAC-7251: OFF(REMOTE) position:
Can be set from the Remote Controller.
If you have disconnected the Remote
Controller, the BASS BOOST is turned OFF.
4 OPERATION switch
This switch is used to select the operation
mode of the amplifier.
· STEREO position:
The amplifier can be used as a stereo
amplifier.
·MONO (Lch) position:
Amplifies the signal input from the left side
only. Set to this position and make bridged
connections to use as a high-power
monaural amplifier. (The input right signal is
not output.)
5 INPUT SENSITIVITY control
Set this control according to the pre-output
level of the center unit connected with this
unit, or to the maximum power output of
the genuine-accessory car stereo.
Use the diagram on the right as a guide.
For the pre-output level or the maximum
power output, refer to the "Specifications"
in the instruction manual of the center unit.
6 Remote controler control (KAC-
7251 only)
When the "BASS BOOST" switch is in the
"OFF (REMOTE)" position, control the Bass
Boost level from the Remote Controller.
· OFF position:
BASS BOOST is OFF.
· +6/+9/+12 position:
Boost the bass sound by +6 dB, +9 dB and
+12 dB, respectively.
NOTE
NOTE
KAC-7251/7201(KE) 1English
02.11.14
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English
5
7 Power indicator
When the power is turned on, the Power
indicator lights.
If the Power indicator does not light when
the power is turned on, the protection
function may be activated. Check whether
there is any indication of trouble.
The protection function is
activated in the following
situations:
This unit is equipped with a protection
function for protecting this unit and your
speakers from various accidents or
problems that can occur.
When the protection function is triggered, the
Power indicator goes off and the amplifier
stops operating.
· When a speaker wire may be short-
circuited.
· When a speaker output contacts ground.
· When the unit malfunctions and a DC
signal is sent to the speaker output.
·When the internal temperature is high and
unit won't operate.
· When a ground wire of the center unit
(cassette receiver, CD receiver, etc.) or
this unit is not connected to a metal part
serving as an electrical ground passing
electricity to the battery's negative -
terminal.
OFF
+6
dB
+12
+9
7
6
Remote controler
(KAC-7251 only)
KAC-7251/7201(KE) 1English
02.11.14
10:30 AM
Page 5