Kenwood L-A1 User manual

KE NWO OC D Ze \e A l Instruction Manual
= INTEGRATED AMPLIFIER

Introduction
Thank you for buying the Kenwood L-A1 integrated amplifier.
Please read this manual carefully to ensure that you get the greatest possible use and satisfaction from your amplifier.
Keep this manual in a safe place for future reference.
Contents Caution: Read the pages marked A\ carefully to ensure safe operation. ‘
es m R Accessories
A
Before
applying
power
3
How
to
use
the
amplifier
12
Make
sure
that
all
accessories
are
put
aside
Listening
through
the
main
source
so
they
will
not
be
lost.
Playing
records
A
Safety
precautions
3
Listening
through
headphones
Muting
the
sound
Remote
control
(1)
A\
Important
safeguards
4
S
P
Z
How
to
record
music
14
Selecting
a
music
source
for
recording
:
og
Listening
to
a
second
music
source
while
recording
About
your
new
Kenwood
L-A1
amplifier
6
ion totind
Recoring
Dubbing
music
fk
;
Listening
to
a
second
music
source
while
dubbing
.
dry
ee
(R6/SUM-3)
12
How
to
set
up
your
new
amplifier
8
Hee
Mn
Me
Temata
Contant)
Troubleshooting
18
Names
of
parts
10
Stand
by mode
of
POWER
switch
Block
diagram
19
Shorting pins (2)
How
to
use
the
remote
control
1
Ass
<A
Inserting
the
batteries
Characteristics
charts
20
Operating the remote control AC plug adaptor (1)
on : {Except for some areas)
Specifications 2) For the unit with a European
a a a AC plug in areas other than
Europe.
N

Before applying power
For Europe
A\ Caution: Read this page carefully to ensure safe operation.
For other countries
important!
Units shipped to Europe are designed for operation on
230 V AC only.
For the United Kingdom
Important!
Units shipped to the U.K. are designed for operation on 240
volts AC only.
The mains plug must be removed from the wall socket prior to
any internal examination.
The wires in this mains lead are coloured in accordance with
the following code:
BlUGsxcesecre etn ated ee Neutral
BLOWN): csccsssevabseceiereevednensipencdieths Live
The wires in this mains lead must be connected to the
terminals in the plug as follows:
Wire colour Plug terminal marking
» (BIUO. ss aishditieeenda nies N or Black
BrOWNinn ccs iestasees tevaasiesdosseaeauatys L or Red
| Brown to
Live
Blue to € )
Neutral
N
Plug -—
Notes:
1.
Ifa
13-amp
plug
is
used,
this
must
be
fitted
with
a
13-amp
fuse.
2.
Ifa
3-pin
plug
with
earthing
contact
is
used,
no
wire
must
be
connected
to
the
E
terminal.
Important!
Units shipped to countries not specified on the left-hand side
are equipped with an AC voltage selector switch on the rear
panel. Refer to the following paragraph for the proper setting of
this switch.
AC voltage selection
This unit operates on 110 - 120 or 220 - 240 volts AC. The AC
voltage selector switch Type A or Type B on the rear panel is set
to the voltage that prevails in the area to which the unit ‘is
shipped. Before connecting the power cord to your AC outlet,
make sure that the setting position of this switch matches your
line voltage. If not, it must be set to your voltage in accordance
with the following direction.
Note: —_
Our warranty does not cover damage caused by excessive line
voltage due to improper setting of the AC voltage selector
switch.
Safety precautions
AC voltage selector switch
Type A =
AC 110- AC 220-
120V~ 240v~
Type B
AC 110- | AC 22e0V~ AC 230-
OvV~ 240V~
Move switch Jever to match your line voltage
with a small screwdriver or other pointed tool.
WARNING: TO PREVENT FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS
APPLIANCE TO RAIN OR MOISTU
As
CAUTION CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK, DO NOT REMOVE
MISK'OF ECEGTRIS SHOCK COVER (OR BACK). NO USER-SERVICEABLE PARTS INSIDE, REFER
DO NOT OPEN SERVICING TO
QUALIFIED SERVICE PERSONNEL.
THE LIGHTNING FLASH WITH ARROWHEAD SYMBOL, WITHIN AN EQUILATERAL TRIANGLE,
IS INTENDED TO ALERT THE USER T
TO THE PRESENCE OF UNINSULATED “DANGEROUS VOL-
TAGE” WITHIN THE PRODUCT'S ENCLOSURE THAT MAY BE OF SUFFICIENT MAGNITUDE
TO CONSTITUTE A RISK OF ELECTRIC SHOCK TO PERSONS.
THE EXCLAMATION POINT WITH!
THE USER TO THE PRESENCE
N AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT
OF IMPORTANT OPERATING AND MAINTENANCE
(SERVICING) INSTRUCTIONS IN THE LITERATURE ACCOMPANYING THE APPLIANCE.

Important safeguards
A
Caution:
Read
this
page
carefully
to
ensure
safe
operation.
Please read all of the safety and operating instructions before operating
For best results, follow all warnings placed on the unit and adhere
to the operating and use instructions. These safety and operating instruc-
tions should be retained for future reference.
this unit.
Note:
Power sources — The unit should be connected
to a power supply only of the type described
in the operating instructions or as marked on
the appliance.
Power-cord protection — Power-supply cords
should be routed so that they are not likely to
be walked on or pinched by items placed upon
or against them, pay particular attention to
cords at plugs, convenience receptacles, and
the point where they exit from the unit.
Grounding or polarization — The precautions
should be taken so that the grounding or
polarization means of this unit is not defeated.
Ventilation — The unit should be situated so
that its location or position does not interfere
with its proper ventilation.
To maintain good ventilation, do not put
records or a table-cloth on the unit. Place
the unit at least 10 cm away from the walls.
Do not use the unit on a bed, sofa, rug or
similar surface that may block the ventilation
openings.
Water and moisture — The unit should not be
used near water - for example, near a bathtub,
washbowl, kitchen sink, laundry tub, in a
wet basement, or near a swimming pool, etc.
Temperature — The unit may not function
properly if used at extremely low, or freezing
temperatures. The ideal ambient temperature
is above +5°C (41°F).
Heat - The unit should be situated away from
heat sources such as radiators, heat
registers, stoves, or other units (including
amplifiers) that produce heat.
Electric shock — Care should be taken so that
objects do not fall and liquid is not spilled into
the enclosure through openings. If a metal
object, such as a hair pin or a needle, comes
into contact with the inside of this unit, a
dangerous electric shock may result. For
families with children, never permit chil-
dren to put anything, especially metal, inside
this unit.
Item 3 is not required except for grounded or polarized equipment.
10.
11,
12.
Enclosure removal — Never remove the en-
closure. If the internal parts are touched
accidentally, a serious electric shock might
occur.
Magnetic fields - Keep the unit away from
sources of magnetic fields such as TV sets,
speaker systems, radios, motorized toys or
magnetized objects.
Cleaning — Do not use volatile solvents such
as alcohol, paint thinner, gasoline, or benzine,
etc. to clean the cabinet. Use a clean dry
cloth.
Carts and stands —- An appliance and cart
combination should be moved with care. Quick
stops, excessive force, and uneven surfaces
may cause the appliance and cart combina-
tion to overturn.

13.
14.
15.
16.
17.
Nonuse periods — The power cord of the unit
should be unplugged from the outlet when left
un-used for a long period of time.
Abnormal smell — If an abnormal smell or
smoke is detected, immediately turn the
power OFF and pull out the power cord.
Contact your dealer or nearest service
center.
Damage requiring service — The unit should be
serviced by qualified service personne! when:
A. The power-supply cord or the plug has
been damaged; or
B. Objects have fallen, or liquid has been
spilled into the unit; or
C. The unit has been exposed to rain; or
D.The unit does not appear to operate
normally or exhibits a marked change in
performance; or
. The unit has been dropped, or the enclo-
sure damaged.
m
Servicing - The user should not attempt to
service the unit beyond that described in the
operating instructions. All other servicing
should be referred to qualified service
personnel.
AC outlets — Do not connect other audio equip-
ment with a power consumption larger than
that specified to the AC outlet on the rear
panel. Never connect other electrical units,
such as an iron or toaster, to it to prevent
fire or electric shock.
A\ Caution : Read this page carefully to ensure safe operation.
Stro6mbrytarens POWER beredskapslage
Indikatorn STAND BY tands efter natkabelns anslutning till
ett vagguttag, oavsett str6mbrytarens POWER ttill/
franslag. Detta anger att en liten mangd strém leds till
komponenten som stéd fér minnesinnehallet.
Detta lage kallas fér beredskapslaget. Str6mbrytaren pa
fjarrkontrollen kan anvandas for att sla pa och av str6mmen sa
lange indikatorn STAND BY lyser.
Virtanappaimen (POWER) valmiustila (STAND BY)
Kun laitteen verkkojohto on liitetty pistorasiaan, valmiustilan
merkkivalo syttyy riippumatta virtanappaimen (POWER) asennosta
(ON/OFF). Merkkivalo osoittaa, etta laitteessa on hieman virtaa
muistin sisaltdjen yllapitoa varten, Tata tilaa kutsutaan
valmiustilaksi. Kun valmiustilan merkkivalo (STAND BY) palaa,
laitteen virta voidaan kytkea ja katkaista kaukosaatimella.
Afbrydertastens (POWER) STAND BY funktion
Nar apparatets stremledning er tilsluttet en stikkontakt, lyser
STAND BY indikatoren, uanset om der er taendt ved afbryderen
pa apparatet eller ej. Det angiver, at apparatet bliver forsynet med
enganske lille mzengde stram til opret-holdelse af hukommelsens
indhold.
Denne funktion kaldes STAND BY. Nar STAND BY indikatoren er
teendt, kan stremmen til apparetet slas til og fra med fjernsty-
ringsenheden.
PA/AV-knappens Stand-by funksjon
Nar stromledningen til dette anlegget er satt i en
vekselstramskontakt, vil STAND-BY indikatorlampen lyse enten
PA/AV-knappen er pa-eller avsiatt. Dette betyr at en viss mengde
strom tilfgres anlegget slik at innholdet i minnet ikke gar tapt.
Denne funksjonen kalles Stand-by. Nar indikatorlampen for STAND-
BY er tent, kan strammen slas PA/AV fra fjernkontrollen.

About your new Kenwood L-A1 amplifier
Tan) e)cenacxe me hvaal-lanlrom-}(erar-]mcomare)(si-m ec] ale)
All the power you need and more
® Super C!
All amplifier circuits in the Kenwood L-A1 amplifier
use our newly developed Super C‘ circuits (Super
Constant Current Cascade Circuit). While most
amplifiers use differential amplifier circuits, in
designing the Super C4 we focused on a new way
of reducing the in-phase noise normally suppressed
by using the common-mode rejection ratio (CMRR)
inherent to differential amplifiers. The result was a
dramatic reduction in the noise generated in the
first stages of the amplifier circuits.
+VCC
Ordinary design
OUT
OUT 2
N41
IN2 0
— ts VES
L-A1
4VCC
CC
e Revolving resistor volume
The master volume of the L-Al amplifier uses a
newly developed large-scale (type 32) revolving
resistor volume. While ordinary volumes have a
slider that moves over the resistor, the slider in the
L-A1 is fixed over the volume while the resistor is
rotated. This design eliminates the connection
formerly created by crimping between the printed
circuit board and the resistor and allows the
amplifier to deliver better sound. This revolving
resistor design also makes it possible to realize
special variant control characteristics which in turn
made it possible for us to use a master volume with
the unbelievably low impedance of 1k Q. This gives
you the low impedance you need in actual use, and
reduces the noise generated from the volume and
main amplifier to the barest minimum.
® Multiple-driver system
The power amplification system uses four parallel push-pull circuits with large-scale transistors (Pc=120W),
which make it possible for the L-A1 to produce strong output even when the impedance of speaker systems
has fallen low at some frequencies. In ordinary parallel push-pull circuits, only the power transistors in the
final stage are connected in parallel, while all other driver transistors in the previous stage are usedin common. .
The multi-driver system used in the L-A1, however, includes a group of driver transistors for each group of
power transistors in a design that connects four groups of Darlington circuits in true parallel. This circuit
structure reduces the load on individual transistors, making it possible to gain a stable circuit operation with
sufficient current and less heat.
Ordinary design L-A1
IN t+-———o OUT iNO———~+ —O OUT

e VIG circuits
The power amplification system also uses voltage
interface gate (VIG) circuits which ensure a clean
source of power for your L-A1 free of impurities
such as ripples, load fluctuation, or other inter-
modulation distortion. From the point of view of
the power amplification system, this results in the
same benefits as would be gained from a far more
powerful power system.
e A heatsink design that separates the
final and driver transistors
The large-scale heatsink with a 7 mm thick base is
used in the power amplifier was designed, and
makes it possible to stand up to even loads of 2 Q.
By laying out the final and driver transistors
separately on both sides of the heatsink, it doubles
as a shield to prevent interference between the
large and low current systems.
e A high-capacity toroidal transformer
The Kenwood L-A1 uses a toroidal transformer that
gives off very little magnetic leakage and responds
well to load fluctuation. Combined with aluminum
electrolytic capacitors and with a capacity of as
much as 450VA per transformer, these transformers
give you all the power you need—and more.
rei cele hem ace ice mere]eliatsime(-1-s1e] a
© Separated blocks for a sturdy, rigid
design
The cabinet of the Kenwood L-A1 uses a
frame design composed of 2 mm thick steel plates
held together with 4 mm screws for the kind of
rigidness you don’t often find. By making the
cabinet tough, we’ve created a sturdy, solid
foundation that assures you of a deep, rich sound.
By adopting a frame design where individual parts
are assembled together into a single cabinet, we
have been able to separate blocks such as the
main and subsidiary power units, the input unit,
and the power supply in order to prevent
interference between individua! components.
e A glass epoxy circuit board
In keeping with our aim of making the cabinet sturdy
and rigid, we have also used a glass epoxy circuit
board for the printed board of the Kenwood L-A1
amplifier. Glass epoxy offers excellent characteristics
and lasts for years. And as a material, glass offers
better rigidity than the phenol resins normally used
in audio equipment.
As a final touch, the board has been firmly fixed into
the frame with solid steel studs.
Other features
@ MC/MM dual-head equalizer
Phono cartridges come in either MM or MC types.
To make the best of both, the Kenwood L-A1 uses
a dual-head equalizer. Although dual head equaliz-
ers are gain-switching equalizer amplifiers, by of-
fering a dedicated first-stage for MM and MC
circuits, they give you all the benefits of a dedi-
cated equalizer amplifier.
® Quality machined and extruded parts
All parts, such as panels, knobs and jacks, etc. have
been either precision-machined or extruded to give
you sure contro! and the high degree of reliability
you need.

How to set up your new amplifier
Connect your equipment to the amplifier as shown in the diagram below.
Please read the individual instruction manuals for all equipment being
connected to the amplifier.
Do not plug in the power until after all connections have been completed.
The diagram shows an example of how to connect components to lines 1-3.
Use this as an example of how to properly connect your own equipment.
Digital audio tape (DAT) 1 or Digital audio tape (DAT) 2 or
cassette tape deck 1 cassette tape deck 2
Tuner
(>
—_leZ)
Record player
GND (ground) terminal
Balance input terminals ?
For connection to
wall socket
CD player
@ PHONO terminal shorting pins
When the PHONO terminal is not used, connect the
attached shorting pins to the PHONO terminal. Do not For BS terminals or other devices
connect the pins to the REC terminal.
Speaker (right) Speaker (left)
A message from the laboratory
The ‘L’ in the name ‘L-A1’ stands for laboratory. This is a mark assigned to only the most superbly engineered Kenwood products, and it has
been a mark of pride since our founding. Long years of technological expertise have gone into the making of the L-A1, together with the very
finest of materials, making the L-A1 the very personification of Kenwood quality.
AC outlet for U.K.
Caution
= When using the AC outlet equipped with this
[ea] unit, be sure to consult your dealer for the
corresponding plug.
e External power socket
SWITCHED socket (capacity of 200W):
Plugs for the tuner, cassette tape deck, record player, CD
player and other equipment may be inserted into this socket
so that, if the POWER switch for each of the individual com-
ponents is left on, then the components may be turned on and
off simply by turning on the POWER switch of the main unit.
Under no circumstances should devices totaling over 200W
be connected.

The balance input terminals
TT
The GND (ground) terminal
The GND cord of the record player should be
connected here.
The balance terminals provide a professional
connection method for use at broadcast sta-
tions and in other professional applications.
These terminals may be used for connecting
any equipment with output balance terminals.
To connect your equipment, use either com-
mercially available cables or the Canon ca-
bles that come with your equipment. The end
of the Canon cable without a lock switch is the
end which should be connected to the input
terminal (i.e., balance terminal) of the am-
plifier.
To remove the input terminal from the am-
plifier, press the terminal release lever while
removing the plug.
b=
¢
Insert
the
connecting
cords
firmly
into
their
sockets.
Inserting
these
cords
loosely
may
result
in
noise
or
the
loss
of
sound
altogether.
e
When
inserting
or
removing
the
connecting
cords,
aiways
be
sure
to
first
remove
the
power
cord
from
its
socket.
Inserting
of
removing
the
connection
cords
with
the
power
cord
in
its
socket
may
result
in
the
faulty
operation
of
or
damage
to
the
amplifier.
¢
Donot
connect
any
equipment
with
specified
power
requirements
in
excess
of
the
maximum
power
displayed
above
the
socket
on
the rear
of
the
unit.
How to connect the speakers
Connect the speakers in such a way that the core of the wire does not come into contact with any
terminal other than the speaker terminal.
Prepare the wire for Loosen the
é Ei Insert the speaker
connection. terminal cap.
EB Tighten the
wire.
terminal cap.
20mm
= a / my, (SLI
ae.
g
X SX
(Remove the covering to
expose the core of the
wire.)
Speaker impedance
Use speakers with an impedance from 4 to 16 Q. Under no circumstances should you use speakers
with an impedance less than 4 Q.
° Crossing the jeft and right terminals, or inserting the plus and minus terminals incorrectly may result in muddled sound
where instruments cannot be heard clearly, or in an unnatural, monotone sound. Please be sure to connect the speaker
wires correctly.
¢ Do not cross the plus and minus (+ or -) or left and right (L or R) terminals when connecting the speaker cords.

Names of parts
ON/STAND BY indicator VOLUME CONTROL knob
Pressing the POWER key
causes this indicator to
flash for approximately 5
seconds, after which it
enters the ON state
Remote control Spotlight
signal detector
SOURCE indicator
The red indicator lights up in
INPUT mode;
The orange indicator lights up in
REC OUT mode;
When all indicators are off, the
amplifier is in REC OUT OFF
mode, and no recording may be
done.
Vvouwume| conTRoL
PHONES jack MUTING
key / indicator
INPUT/REC OUT switching
key / REC OUT indicator
POWER key SPEAKERS OFF
key / indicator
CARTRIDGE MM/MC key
/ MC indicator
SOURCE selector knob
A message from the laboratory
Class A operation of the driver stage
The power amplification stage of most amplifiers have class B operation. But in the Kenwood L-A1, in order to fully drive the finai transistors, we've designed the
previous drive stage to have class A operation even under a load of only 4 Q. This reduces the actual amount of distortion in the power amplification stage to levels
never before realized, and allows you to enjoy clear, dynamic sound like never before.
Stand by mode of POWER switch
When the power cord of this system is plugged
into an AC outlet, the STAND BY indicator lights up
regardless of the ON/OFF setting of the POWER
switch. This indicates that a small amount of
current is being supplied to the unit to back up
the memory contents. This mode is referred to as
the Stand By mode. While the STAND BY indicator
is lit, the power of the system can be switched
ON/OFF from the remote control unit.
Speaker protection circuits
When the ON/STAND BY indicator begins flashing
rapidly, it means that the plus (+) and minus (-)
polarity of the speakers has been short-circuited.
If this happens, press the POWER key to turn off
the power, reverse the speaker connections, and
press the POWER key to turn on the power once
again. The amplifier should then return to normal
operation.
10

How to use the remote control
INPUT SOURCE selector keys
TAPE 2 TAPE1 PHONO
VOLUME CONTROL keys
POWER MUTING
POWER key
LINE 3. LINE 2 LINE 1 BALANCED
VOLUME
MUTING key
KENWOOD
REMOTE. CONTROL. UNIT
RC-A1
Model name: RC-A1 (infrared signaling)
EEE Ses KEES
So SILI
Inserting the batteries
EJ Open the cover at the bottom of the
unit.
Line up two AA dry batteries {R6/SUM-3) with
the plus/minus markings inside the remote
control unit.
EW close the cover.
Operating the remote control
A
Hold the remote control with the top of the
unit facing the remote control signal detector
and press the keys. The remote control may
be operated within the area shown in the
diagram below. When pressing keys con-
tinuously or in sequence, press each key
firmly and wait approximately one second
before pressing the next key.
J--—— Remote control
signal detector
Approximately
6 meters
Operating area of
the RC-A1 remote
control unit
Notes
¢ The batteries included at the time of purchase
may have already been used for testing the
operation of the amplifier, thus may have a
shorter life.
* If you find that you have to stand closer than
usual to the main unit in order to use the remote
control, please replace both batteries.
¢ Direct sunlight or high-frequency radiation from
fluorescent lamps (inverter-type lamps, etc.) on
the signal detector may result in the remote
control failing to work properly. If this happens,
please place the amplifier in a location free of
such interference to ensure proper operation.
11

How to use the amplifier
VOLUME
CONTROL
knob
SOURCE
selector
knob
/
indicator
Spotlight
LINE 3. LNE2 LINE 1 BALANCED
vouumeE
jsonTROL
=
Fy
-
;
ieee
Po:
|
in]
nee
e
oa
e
he
Bn
Bue
|
INPUT
SOURCE
4
at
selector keys
TAPE1 PHONO
VOLUME CONTROL
@
#
LLB
;
keys
g
corer
ee
<>
i
aeetes
ane
i.
MUTING
key:
stenco wrefaareo anmunean LA |
MUTING
key / indicator
INPUT/REC OUT switching key / KENWOOD
REC OUT indicator 4 REMOTE CONTROL UNIT
: RC-A1
SPEAKERS OFF key / indicator
POWER key CARTRIDGE MM/MC
key / MC indicator
A message from the laboratory
Use of a photo coupler to separate the audio and control systems
The
Kenwood
L-A1
amplifier
has
a
special
microcomputer
located
inside
to
handie
the
functioning
of
the
remote
control
unit.
However,
this
has
the
disadvantage
of
generating
noise
which
is
capable
of
adversely
affecting
the
audio
system.
That’s
why
we
designed
a
layout
where
the
power
unit
is
separated
from
the
power
transformer
and
where
all
relay
and
other
control
signals
are
sent
as
floating
transmissions
routed
through
the
photo
coupler.
This
complete
separation
of
the
audio
and
control
systems
makes
it
possible
to
eliminate
noise from
this
microprocessor.
12

@ Listening through the main source
1 Press the POWER key to turn on the amplifier.
Vv Main unit v Remote Control
ON/STAND BY
ie Confirm the amplifier is in INPUT mode.
¢ lf the REC OUT indicator lights up, press the
INPUT/REC OUT switching key to turn it off.
Confirm the amplifier aes our
is in INPUT mode.
'
O =~ O =e—e 0 <= OO '
LINE 3 LINE2 LINE 1 BALANCED '
'
i
Oo~—-«-, O Fok 1
TAPE 2 TAPE 1 FRAO '
1
¢ The REC OUT indicator is off.
elf the REC OUT indicator lights up, press the © The PHONO source indicator lights up red.
INPUT/REC OUT switching key to turn it off.
Press the CARTRIDGE
MM/MC key to select the
setting that matches
your cartridge.
¥ Main unit Vv Remote Control
Turnthe SOURCE | Use the INPUT
selector knob to | SOURCE selector keys
select
PHONO.
|
to
select
PHONO.
e\f you are using an MC cartridge, press the
CARTRIDGE MM/WC key so that the MC indica-
tor lights up.
LINE 1 ‘BALANCED
TAPE 2 TAPE 1 PHONO
Place a record on the record player and
start playing.
V Main unit
Turn the SOURCE selector knob
ey to select the music source.
Vv Remote Control
Use the INPUT SOURCE selector keys
to select the music source.
LINE 2 LINE 14 BALANCED
LINE 3
TAPE 2 TAPE 1 PH
¢ The SOURCE indicator, for the music source you have selected, lights up.
4. | Insert the recording media and play from the selected source.
Vv Main unit
Vv Remote Control
Turn the VOLUME CONTROL | Use the VOLUME CONTROL keys to
5 | knob to adjust the loudness. adjust the loudness.
¢ The numbers on either side of the VOLUME CONTROL knob are for use as a guide in adjusting the volume.
The current volume level is indicated by lighting up the number for which the volume is set. Turning the
knob counterclockwise as far as it will go reduces the volume level to zero.
| Listening through headphones. _ _. Mutingthesound
Insert the headphone plug FHONES =
into the PHONES jack. Press the MUTING key.
4 ¥ Main unit Vv Remote Control
Press the SPEAKERS
OFF
key.
;
dienes
e The SPEAKERS OFF indicator
lights up, and no soundis output
from the speakers.
*To reset, simply press the
SPEAKERS OFF key again.
SPEAKERS OFF
¢ The MUTING indicator lights up and the sound is
Vv Main unit Vv Remote Contro! minted.
at Turn the VOLUME Use the VOLUME * To reset, simply press the MUTING key again.
a= CONTROL knobto CONTROL keys to
adjustthe volume.
adjust the volume.
VOLUME
13

How to record music |
wed Baton ae
eETy
it BS
Maa
HOON
_ SOURCE selector
: knob / indicator
KENWOOD
LINE 3) LUNE 2 UNE 1 BALANCED
INPUT SOURCE
selector keys
| TAPE.2 TAPE1 PHONO
POWER
MUTING
KENWOOD
REMOTE CONTROL UNIT
RCA1
INPUT/REC OUT switching
key / REC OUT indicator
A message from the laboratory
Bus bars lower impedance in the GND terminal and power unit
The Kenwood L-A1 uses a bus bar in its input switching and output circuits. In the input switching unit, this design reduces the potential difference to zero between
the GND in individual components and that in the amplifier to give you the ideal arnplification. Bus bars have also been included in the plus power supply, output, : F
and in the plus and minus power supplies of the output circuits to reduce signal loss to the lowest possible fevel. By designing a layout where the three bus bars :
in the output circuits run in parallel, we have also succeeded in reducing the amount of undesired radiation generated from the main power unit.
14 .

M@ Selecting a music source for recording
Press the INPUT/REC OUT switching key Turn the SOURCE selector knob to select
1
|
to
select
REC
OUT
mode.
the
source
from
which
you
want
to
record.
Start the cassette tape deck to Start the music source from
begin recording. which you want to record.
¢ If the REC OUT indicator is off, press the INPUT/
REC OUT switching key to turn it on.
¢ The SOURCE indicator for the music source you
have selected will light orange for approximately
five seconds before turning red (returning to INPUT
mode).
¢ Note that you may also record simultaneously
on two cassette tape decks.
* When the power for the selected recording device
is off, or when you are not recording, be sure to
keep the REC OUT mode set to OFF. (REC OUT
made is set to OFF when all the source indicator
lights are off.)
© The REC OUT indicator lights up.
e¢ The next step must be performed within five
seconds, or the amplifier will return to INPUT
mode.
Monitoring recording
Connecting a 3-head cassette tape deck to the Begin playing from the selected recording
Kenwood L-Ai lets you compare the pre-recording source.
and post-recording sound from the tape while
recording is still in progress.
Listening to a Second music source |
while recording
Vv Main unit v Remote Control
Turn the SOURCE | Use the INPUT SOURCE
selector knob to | selector keys to select
select the music | the music source from
source from which | which you wanttolisten.
you want to listen.
pees To monitor recording while it is in progress, follow
‘geen, ge 6 gue, 6g, §«=s-s the. procedure below.
Start recording from the source you have
selected.
° Begin recording by following the procedure de-
scribed above in “Selecting a music source for
«Please
begin
recording
using
the
procedure
qd
abe
recording.
described above in “Selecting a music source for
recording.
a
ee
&
Switch
the
MONITOR
switch
of
the
3-head
Sais
tage ~
corlongs
1 | Connect a 3-head
cassette
tape
deck
to
cassette
tape
deck.
5
&
either
the
TAPE 1
or TAPE
2
terminal.
Confirm the amplifier is in INPUT mode.
¢ The REC OUT indicator is off.
Start playing from the source you have
selected.
Vv Main unit
Turn the SOURCE
selector knob to
select TAPE 1 (or if
the deck is connec-
ted to TAPE 2, then
select TAPE 2).
‘Vv Remote Control
Use the INPUT
SOURCE selector
keys to select either
TAPE 1 or TAPE 2.
15

How to record music
SOURCE selector
knob / indicator
KENWOOD
VOLUME CONTROL
SPEAKERS OFF
ereneo mrccrlareo ampunen LA ]
INPUT/REC OUT switching
key / REC OUT indicator
A message from the laboratory
Selection of the parts used in the L-A1
We have carefully selected every one of the parts used in the Kenwood [-A1 to ensure that they all offer excellent sound and performance with a reliability that
ensures the quality will last. We checked the feel of every control before making our decision. We even requested one manufacturer to design an entirely new
knob for use in the source selection rotary switch, having several different prototypes made and selecting the one that we knew would offer you the surest feel.
16
LINE 3
LINE.2 LINE 1 BALANCED
‘4
INPUT SOURCE —4t+
selector keys
TAPE 2
TAPE1 PHONO
POWER
KENWOOD
REMOTE CONTROL UNIT
MUTING
RC-A1

| Dubbing music (from TAPE 1 to TAPE 2) *To dub from TAPE 2 to TAPE 1, follow the steps in parentheses below.
Press the INPUT/REC OUT switching Turn the SOURCE selector knob Start recording on cassette tape Start the cassette in cassette tape
1 | key to select REC OUT mode. to select TAPE 1 (TAPE 2). deck 2 (cassette tape deck 1). deck 1 (cassette tape deck 2).
REC OUT
¢ The REC OUT indicator lights up.
¢ The next step must be performed within five
seconds or the amplifier will return to INPUT
mode.
hing to a second music source
_ while dubbing ee
Begin dubbing.
© Beginrecording using the procedure described above
in “Dubbing music.”
¢ If the REC OUT indicator is off, press the INPUT/
REC OUT switching key to turn it on.
¢ The SOURCE indicator for the music source you
have selected will flash orange for approximately
five seconds before turning red (returning to INPUT
mode).
Confirm the amplifier is in INPUT mode.
e The REC OUT indicator is off.
Vv Main unit
Turn the SOURCE
selector knob to
select the music
source to which
you wantto listen.
v Remote Control
Use the INPUT SOURCE
selector keys to select
the music source from
which you want to
listen.
UNE 3 UNE2 LINE1 — BALANCED
TAPE 2 TAPE1 PHONO
Start playing from source you have
selected.
17

e
Troub leshooting Before you contact your service representative, check the following list.
SOLUTIONS
¢
Press
the
SPEAKERS
OFF
key
to
turn
off
the
SPEAKERS
OFF
indicator.
¢
Reconnect
the
speaker
cords
according
to
the
procedure
PROBLEM
No sound
POSSIBLE CAUSES
e SPEAKERS OFF indicator is lit.
MAIN UNIT
e Speaker cords aren't properly connected.
18
REMOTE CONTROL UNIT
Volume has been turned down to zero.
Amplifier muting is on and the MUTING indicator is lit.
Audio cords are crossed or aren't properly connected.
The shorting pin is still connected to the REC terminal.
described in “ How to set up your new amplifier" on page
8.
Adjust the volume.
Press the MUTING key to turn off the MUTING indicator.
Check that the audio cords are properly connected.
Remove the shorting pin from the terminal.
ON/STAND BY indicator is blinking
rapidly and there is no sound from
the stereo
Speaker cords are short-circuited.
Press the POWER key to turn off the power before replac-
ing the speaker cords in their correct places. Then press
the POWER key again to turn the power back on.
No sound from one of the speakers
Youcan hear a strange sound when
the SOURCE selector knob (or the
SOURCE selector keys) is set to
PHONO
You get different volume levels
from the tuner and the record player
PROBLEM
Speaker cord is loose.
The record player's audio cord is not firmly inserted into
the PHONO jack.
The record player's grounding line is not properly
connected.
The output from the tuner is different from the output of
the record player.
The MM/MC mode is improperly set.
POSSIBLE CAUSES
Remote control unit doesn't work
Batteries are dead.
¢ You are too far away from the main unit or you are trying
to operate the remote contro! at too sharp an angle. Also
check that nothing is in the way.
Reconnect the speaker cords according to the procedure
described in “How to set up your new amplifier” on page
8.
Insert the audio cord firmly into the PHONO jack.
Connect the grounding line to the GND terminal on the
rear of the amplifier.
Adjust the volume.
Press the CARTRIDGE MM/MC key to properly set the
MM/MC mode.
SOLUTIONS
e Replace both batteries.
e Try using the remote control again, but within the area
described on page 11.
*
The
Kenwood
L-A1
uses
a
microprocessor
that
may
be
subject
to
external
noise
or
interference
which
would
cause
the
L-A1
to
function
improperly.
If
this
happens,
remove
the
power
cord
from
its
socket
and try the ampiifier once more.
* Do not use giues and fixatives to restore electrical connections as they may result in darnage to your amplifier. Solutions containing oils are particularly dangerous, as they may cause the distortion of
plastic parts.

Block diagram
PHONO EQ AMP
DC SERVO
BALANCE
MM/MC
LINE
TAPE PLAY
200mV
TAPE 1
REC ©
TAPE 2
REC
©)
REC OUT SELECTOR
INPUT SELECTOR
© HEADPHONE
HEADPHONE AMP:
| Bee
-©- POWER AMP
SPEAKERS
‘ ~O [ zesveo | 3V/B
SPEAKER ON/OFF
+
POWER AMP.
1ST STAGE
[
diel
[
+
+
LINE BUFFER AMP.
PRIMARY
POWER
SUPPLY
HEADPHONE AMP [_
RELAY +B
MOTOR VOLUME
RELAY CONTROL
MOTOR VOLUME
PROTECTION
LED
POWER
RELAY
REMOTE
CONTROL
KEY INPUT
19

Characteristics Charts
TOTAL HARMONIC DISTORTION VS. INPUT LEVEL
TOTAL HARMONIC DISTORTION VS. OUTPUT POWER
PRODUCTION CODE : 20999039
WEATHER : FINE TEMP: 23°C MEASURED BY : S.0ONO
MODEL : L-A1
PRODUCTION CODE : 20999039
MODEL : L-A1
2 '92.9.28 DATE
DATE : '92.9.28 WEATHER: FINE TEMP: 23°C MEASURED BY : S.00NO
10
20kHz
1kHz
20Hz
100m
INPUT LEVEL (¥)
MINIMUM
PHONO (MM)
Leh
10kQ
0.1
10m
0.01
Im
VOLUME :
INPUT :
OPERATION :
LOAD IMPEDANCE:
0.001
0.0001
0.00001
(%)
NOILUOLSIG
DINOWAVH
TVLOL
1k
20kHz
IkHz
20Hz
100
10
OUTPUT POWER (W)
-16dB
LINE |
Lech
VOLUME :
INPUT :
OPERATION :
LOAD IMPEDANCE: 829
0.1
(%)
NOLLYOLSIG
DINOWYVH
TVLOL
20