Kenwood KAC-848 User manual

KENWOO
4-CHANNEL POWER AMPLIFIER » Page 2-11
INSTRUCTION MANUAL
MODE D’EMPL ol » Page 12-21
AMPLIFICADOR DE POTENCIA DE 4 CANALES » Page 22-31
MANUAL DE INSTRUCCIONES
KENWOOD CORPORATION
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 callupon your
KENWOOD dealer for information or service on the praduct:
Mode! KAC-848/748 Serial number
© PRINTED IN USA B64-1350-00 (KM)

To prevent injury or fire, take the following
precautions:
e When extending the ignition, battery, or
ground wires, make sure to use automotive-
grade wires or other wires with a 5mm?
(AWG10) 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.
elf 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.
e¢ When replacing a fuse, only use a new one
with the prescribed rating. Using a fuse with
the wrong rating may cause your unfit to
malfunction.
¢ To prevent a short circuit when replacing a
fuse, first disconnect the wiring harness.
Protection function
e If you experience problems during
installation, consult your Kenwood dealer.
If the unit does not seem to be working right, —
consult your Kenwood dealer.
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 voiatile solvents such as
paint thinner and alcohol. They can scratch the
surface of the panel and/or cause the indicator
letters to peel off.
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.
Accessories
Terminal cover
Self-tapping screws
- (84 x 16 mm) @)>
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.
@ 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.
_ I The protection function activates in the following
situations:
e When a speaker wire may be short-circuited.
¢ When a speaker output contacts ground.
e When the temperature of internal parts exceeds 120°C (248°F).
¢ 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
Power indicator
ground passing electricity to the battery's negative © terminal.
2 English

Installation procedure
1.Remove
the
ignition
key
and
disconnect
the
negative
©
terminal
of
the
battery
to
prevent
short
circuits.
2. Set the unit according to the intended usage.
3.
Connect
the
input
and
output
cables
of
the
units.
4.Connect the speaker wires.
5.
Connect
the
power
wire,
power
control
wire
and
grounding
wire
following
this
order.
6. Install the unit in the car.
7.Connect
the
negative
©
terminal
of
the
battery.
¢
Be
sure
to
turn
the
power
off
before
changing
the
setting
of
any
switch.
*
If
the
fuse
blows,
check
wires
for
shorts,
then
replace
the
fuse
with
one
of
the
same
rating.
e
Check
that
no
unconnected
wires
or
connectors
are
touching
the
car
body.
Do
not
remove
caps
from
unconnected
wires
or
connectors
to
prevent
short
circuits.
¢
Connect
the
speaker
wires
to
appropriate
speaker
connectors
separately.
Sharing
the
negative
wire
of
the
speaker
or
grounding
speaker
wires
to
the
metal
body
of
the
car
can
cause
this
unit
to fail.
*
After
installation,
check
that
the
brake
lamps,
winkers,
and
wipers
work
properly.
Installation
Self-tapping
screw
es
,
(24
x
16
mm)
YG
Ya
La
Installation board, etc. eee...
(thickness : 15 mm or more)
¢
Since
the
power
amplifier
has
no
parts
which
require
operation,
it
can
be
installed
at
a
position
away
from
the
driver's
seat
without
any
hindrances.
As
generally
accepted
positions
for
its
installation,
places
such
as
inside
the
trunk,
etc.
can
be
considered.
e Use the extension cables. (Optional.)
pe
ene]
Om
|
im] am]
am]
om
_|
PReReabie
|
CAZSL_|
CA128.
|
CAZ2SL_|
——
|
CAS2SL_
[RCA
cable
(o7mm)
|
CASWL
|
CA7SWL
|
CA2aWL
|
——
|
CASSWL
|
— |
[_AcAUTION |
¢
Do
not
install
the
unit
under
the
carpet.
Otherwise
heat
build-up
occurs
and
the
unit
may
be
damaged.
=
e
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.
¢
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
3
obstruct
driving.
If
the
unit
comes
off
due
to
a
shock
and
hits
a
person
or
safety
part,
itmay
=
cause
injury
or
an
accident.
:
ae
ee
.
¢
After
installing
the
unit,
check
to
make
sure
that
electrical
equipment
such
as
the
brake
lamps,
turn
signal
lamps
and
windshield
wipers
operate
normally.
CA-G5W |
English 3° °*

Controls
This
is
a
4
channel
amplifier
including
2
stereo
amplifiers
i
in
a
body.
One
amplifier
is
referred
to
as
amplifier
A
and
the
other
is
amplifier
B.
This unit
is
compatible
with
a
large
variety
of
systems
by
combining
the
switches
and
functions
described
in
the
following.
‘KAC-848 ®
KAC-848
KAC-748
INPUT.
ap :
10088 is0 . :
80 FILTER OPERATION
GD of 7
HPE l LPF
FREQUENCY(Hz) == STEREO
L+R
eS see
STEREO, Stereo | Txononay Lasee FREQUENCY (Hz)
‘Amplifier A
@ Fuse (20 Ax 2 : KAC-848) © Amplifier A speaker sa cl
(30 Ax 1: KAC-748) terminals
@ Battery terminal © Amplifier B speaker output
terminals
@) Ground terminal
@ Power control (REMOTE) terminal
4 English

SPEAKER
OUTPUT
terminals
¢ Stereo Connections:
When
you
wish
to
use
the
unit
as
a
stereo
amplifier,
stereo
connections
are
used.
The
speakers
to
be
connected
should
have an impedance of 2Q or greater.
When multiple speakers are to be
connected,
ensure
that
the
combined
impedance
is
2Q
or
greater
for
each
channel.
Bridged Connections:
When
you
wish
to
use
the
unit
as
a
high-
output monaural amplifier, bridged
connections are used. (Make connections
to the LEFT channel (+) and the RIGHT
channel
(-)
SPEAKER
OUTPUT
terminals.)
The
speakers
to
be
connected
should
have an impedance of 4Q or greater.
When multiple speakers are to be
connected, ensure that the combined
impedance is 4Q or greater.
The
rated
input
of
the
speakers
should
be
no
less
than
the
maximum
output
of
the
amplifier.
Otherwise
malfunction
may
result.
@
Speaker
level
input
terminals
(KAC-748
only)
FREQUENCY control
When the FILTER switch is set to the HPF
(High-Pass
Filter)
or
LPF
(Low-Pass
Filter)
position, the threshold frequency can be
adjusted with this control.
©
FILTER
switch
High-pass
or
low-pass
filtering
can
be
applied
to
the
speaker
output
according
to
the
setting
of
this
switch.
@ OPERATION switch
The amplification methods of the signais
input to amplifiers A and B can be selected
independently
according
to
the
setting
of
this switch.
¢ STEREO position:
The amplifier can be used as a stereo
amplifier.
« L+R position:
The input left and right signals are
combined before being amplified. Use this
position when the unit is used for
subwoofer
speakers
or
the
L+R
(monaural)
sound is required.
°
+ 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 es is
not output.)
@ INPUT SENSITIVITY control
Set
this
contro!
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.
Yos 03
(..
KAC-748 only «***°°
\ van MAX
w)
For the pre-output level or the maximum
power
output,
refer
to
the
“Specifications”
in
the
instruction
manual
of
the
center
unit.
@ RCA cable ground lead terminal
@ INPUT SELECTOR switch
This
switch
selects
the
input
method
of
the
signals
to
be
amplified
by
amplifiers
A
and
B. : '
a
Aa @
- AB position: meee
Amplifies both of the signals input to
amplifiers A and B.
- A position:
Amplifies
only
signal
input
amplifier
A
with
both
amplifiers
A
and
B.
@ Amplifier A LINE IN terminal
@® Amplifier B LINE IN terminal
@ LINE OUT terminal
These
jacks
output
respectively
the
signals
input to amplifiers A and B. They always
output
the
stereo
signals
regardless
of
the
position of the OPERATION switch.
English 5 =

Connection
RCA cable connection
Do
not
connect
cables
and
!eads
to
both
RCA
cable
input
jacks
and
the
speaker
input
terminals
simultaneously,
for
this
may
cause
malfunction
or
damage.
RCA
cable
ground
terminal
[A]
Left
input
[B}
Left
input
4 [B
RCA
cable
}
us
Aap
iether
(Commercially
available
part)
<i
Front
output
p>
CENTER UNIT =S—>
(Cassette receiver,
CD receiver, etc.)
mn =0-8
Rear
output
=>
:
RCA cable ground terminal
When
using
an
RCA
cable
with
a
ground
lead
attached,
connect
the
ground
lead
to
this
terminal.
Do
not
use
this
terminal
for
power
source
grounding.
This
unit
will
be
damaged
if
the
power
source
grounding
wire
is
connected
to
this
terminal.
=
Speaker
level
input
connection
(KAC-748
only)
Connect
the
unit
by
inserting
it
in
mes
connection
between
the
genuine-accessory
car
stereo
and
speakers.
To
Power
control
[A]
Left
input
See
(REMOTE)
terminal
*
cy
Right
input
Left input
a Front Left -
tt
Av
Genuine-accessory ya} Front Right
car
stereo
BY
Rear
Left
Bi;
Rear
Right
Lead
terminal
(Commercially available parts)
=e :
6 English

—_—
*
The
genuine-accessory
car
stereo
shall
have
a
maximum
power
output
of
no
more
than
25
W.
*
Do
not
connect
the
speaker
output
leads
from
a
power
amplifier
(Optional)
to
the
Seeeker
input
terminals
of
this
unit,
for
this
may
cause
malfunction
or
damage.
*
Do
not
connect
cables
and
leads
to
both
RCA
cable
input
jacks
and
the
speaker
input
terminals
simultaneously,
for
this
may
cause
malfunction
or
damage.
*
Connect
the
power
control
lead
to
a
power
supply
which
can
be
turned
ON/OFF
by
the
ignition
key
switch
(ACC
line).
With
this
connection,
shock
noise
may
be
generated
when
the
power
of
the
genuine-accessory
.
car
stereo
is
switched
ON/OFF.
H Speakers wire connection
(Stereo Connections)
Ke) se) Lead terminal
FUBETOA) ——4
BMo
Speaker output terminals
CS rer Right speaker
Rear Left speaker
+)
[B} Left steak
cal
(Bridged Connections}
@o
Speaker output terminals.

Connection
@
Speaker
Selection
*
The
rated
input
power
of
the
speakers
that
are
going
to
be
connected
should
be
greater
than
the
maximum
output
power
{in
Watts)
of
the
amplifier.
Use
of
speakers
having
input
power
ratings
that
are
less
than
the
output
power
of
the
amplifier
will
cause
smoke
to
be
emitted
as
well
as
damage.
lt
©
The
impedance
of
the
speakers
that
are
going
to
be
connected
should
be
2Q
or
greater
(for
stereo
connections),
or
4Q
or
greater
(for
bridged
connections).
When
more
than
one
set
of
speakers
are
going
to
be
used,
calculate
the
combined
impedance
of
the
speakers
and
then
connect
suitable
speakers
to
the
amplifier.
Examples:
Bridged Connections (4Q) __
300 W or greater
200 W or greater
Stereo
Connections
(4Q)
100 W or greater
70 W or greater
(ep
os
200W =
a2) oak
Maxirnum
output
of
Combined
x
the
amplifier
impedance
Rated
input
power
and
impedance
of
the
speakers
@
Power
wire
connection
To
prevent
fire
caused
by
a
short
in
the
wiring,
connect
a
fusible
link
or
breaker
nearby
the
battery's
positive
terminal.
;
Wiring
e
If
a
buzzing
noise
is
heard
from
the
speakers
when
the
engine
is
running,
connect
a
line
noise
filter
(optional)
to
each
of
the
battery
wire.
*
Do
not
allow
the
cord
to
directly
contact
the
edge
of
the
iron
plate
by
using
Grommets.
e
Connect
the
ground
wire
to
a
metal
part
of
the
car
chassis
that
acts
as
an
electrical
ground
passing
electricity
to
the
battery's
negative
©
terminal.
Do
not
turn
the
power
on
if
the
ground
wire
is
not
connected.
¢
Be
sure
to
attach
a
protective
fuse
into
the
battery
wire
close
to
the
battery.
Use
a
protective
fuse
having
a
capacity
that
is
about
10
A
higher
than
the
maximum
current
drawn
by
the
amplifier.
e
Use
vehicle-type
(fire-resistant)
power
supply
wiring
wire
for
the
battery
wire
and
the
ground
wire.
The
current
capacity
of
the
power
supply
wiring
wire
should
be
about
10
A
higher
than
that
of
the
protective
fuse
capacity
(which
means
about
20
A
higher
than
the
maximum
current
drawn
by
the
amplifier).
e
When
more
than
one
power
amplifier
are
going
to
be
used, use
a
power
supply
wiring
wire
and
protective
fuse
of
greater
current-handling
capacity
than
the
total
maximum
current
drawn
by
each
amplifier.
Example:
One
Power
Amplifier
Is
Used
Viode
Viaximum
Current
Protective
ruse
ross-sectional
Area
of
Wiring
|
Drawn
Wire
(AWG)
KAC
848]
38A—=«_«dSOAXx1125Ax2)_
|
5
mm’
(AWG
10)
or
greater
x1
KAC-748
40Ax1[20Ax
2]
5
mm?
(AWG
10)
or
greater
x
8 English

~
Lead terminal
loc eeoe
: y (Commercially available parts)
eoeee Terminal cover
Power terminal
Power control wire
Battery wire Ground wire
Lead terminal
.«e(Commercially
available
parts)
Protective
Fuse -
Power terminal
Connect
to
their
respective
terminals
the
power
control
wire,
power
supply
wire,
and
ground
wire,
all
of
which
pass
through
the
associated
terminal
cover.
Once
the
connections
are
complete,
place
the
cover
on
the
terminal
section.
System
examples
|
|
@
Full-range
4-channel
+
Subwoofer
system
put
OPERATION FRTER g SING
OFF
wate 2 Qe
pe
mo @ eenccccccccccccsaveceseces
PUTER A)
aoe
Amplifier
English 9

System examples
w High-pass (100 Hz) + Subwoofer (100 Hz) system
eee SORT
aos stesennensenssnceneratnars | CENTER UNIT
wien fig O- & Switch setting
Switch setting
Switch setting
{High pass) ” Subwoofer
(L + R) (Bridged)
@Principle of Tri-mode
Method of frequency band division using a coil and capacitor---in case of 6dB/oct. slope
Coil (L): Passes low peciibacios and blocks high
frequencies. (Low pass}
_ Capacitor (C): Passes high frequencies and blocks low
frequencies. (High pass)
Crossover Frequency
159000
=
{uF
C
fexR
fc=Cut
of
Frequency
(Hz)
Frequency
i‘
159
xR
H)
R=Speaker
Impedance
(Q)
@Example:
When it is required to set a crossover frequency of 120 Hz using speakers with an
impedance of 4 ohms.
Prepare commercially-available coi! and capacitor with the closest ratings to the results .
calculated from the formula above. The capacitor rating should be as close as possible to 331.25 _
(uF) and the coil rating should be as close as possible to 5.3 (mH).
¢ If you wish to bridge-connect a speaker, the speaker impedance must be no less than 4 ohms. -
Connecting a speaker with an impedance lower than 4 ohms may damage the unit.
¢ Be sure to connect capacitors to speakers to which high frequencies will be passed. -Failure to
do so will result in a drop of the combined impedance with the subwoofer.
¢ Ensure that the withstand voltage and current ratings of the capacitors (C) and coils (L) a are
sufficient.
10 English