Kenwood Nine GX User manual

AM-FM STEREO RECEIVER
model Nine G X
INSTRUCTION
MANUAL
Poe very
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KENWOOD
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INTRODUCTION
The purpose of this manual is to acquaint you with
the operating features of this receiver. You will
notice that in every detail of planning, engineering,
styling, operating convenience, and adaptability,
we have sought to anticipate your needs and
desires.
We suggest that you read through this manual
carefully. Knowing how to set up the receiver, to
the best advantage, will enhance your listening
pleasure right from the start. You will also
become aware of the ease with which you can
adjust the receiver to meet your special re-
quirements.
SERIAL NUMBER
Record your SERIAL NUMBER on the spaces
designated on the warranty card. You will find the
serial number on the back of the receiver.
AFTER UNPACKING
After unpacking, we recommend that you inspect
the receiver for any possible shipping damage. If
your receiver is damaged or fails to operate, notify
your dealer immediately. If your receiver was
shipped to you directly, notify the shipping com-
pany without delay. Only the consignee (the per-
son or company receiving the receiver) can file a
claim against the carrier for shipping damage.
We recommend that you retain the original carton
and packing materials to prevent any damage
should you transport or ship your receiver in the
future.
INSTALLATION PRECAUTIONS
a) Avoid locations subject to direct sunlight.
b) Avoid high or low temperature extremes.
c) Keep the receiver away from heat radiating
source.
d) Choose stable locations with as little vibra-
tion and dust as possible.
WARNING:
TO PREVENT FIRE OR SHOCK
HAZARD, DO NOT EXPOSE
THIS APPLIANCE TO RAIN OR
MOISTURE
2 Model Nine GX
AC VOLTAGE SELECTION
This
receiver
operates
on
AC
120V,
220V
or
240V.
The
AC
Voltage
Selector
Switch
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.
Stopper
plate
Screw
Lever
AC
120V~
AC 220V~
ce
(6
DmD|e
AC 240V~
Position © () (] CJ +)
1. Remove screw and stopper plate.
2. Slide lever to your line voltage.
3. Lock lever with stopper plate
and screw.
AC VOLTAGE SELECTOR SWITCH
i

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SYSTEM CONNECTION DIAGRAM ........csccsccscssceseessesesteseeseseees 4
SYSTEM CONNECTIONS o.scsciccscu; osvessdtsnsctiaysesdivsseederotscunssby tents 5
CONTROLS, INDICATORS AND CONNECTORS...........0ccc0c00 8
PERATING INSTRUCTI WITHOUT USI
CONTENTS OLBYUNIT) scenes ensues nanan 10
OPERATING INSTRUCTIONS (WITH USING DOLBY UNIT)....... 12
DOLBY
NR
MODE
CHART
........cccccccsccscsssssestesteseerestesesveees
16,
17
BLOCK
DIAGRAM,
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18
SPECIFICATIONG..........
FEATURES
80 watts per channel, min. RMS both
channels driven at 8 ohms 20 Hz to 20,000
Hz with no more than 0.03% total harmonic
distortion.
Complete Dolby* facilities for all program
source.
a) Reception of Dolby encoded FM pro-
gram.
b) Taping of Dolby encoded FM programs
with simultaneous decoding and
monitoring.
c) Dolby encoding when taping from any
program source, Dolby recording of any
Dolbyized tape.
d) Providing the Dolby circuit to a tape
deck without Dolby NR.
. Automatic 2-hour Shut-off Timer Control.
. Two POWER/LINE LEVEL meters for check-
ing power output level, input level and
Calibration level of Dolby NR system.
5. Bass, Mid and Treble’s Triple Tone Controls
with true defeat switch.
6. Useful push bottom type input SELECTORS.
7. MIC MIXING system for adding a voice of
your own.
8. High sensitive, low distortion FM_ station
reception.
9. Many useful functions: Dolby NR mode
selector, 400 Hz oscillator for calibrating the
Dolby NR system, Recording and play level
adjustor for Dolby NR system, Power meter
range selector 3/150W, Loudness control,
Mode selector Mono/Stereo, FM Muting,
Subsonic Filter, High Filter, De-emphasis
selector 50/75 us etc.
* Dolby and the double-D symbol are trade marks of Dolby
Laboratories.
Noise reduction system is manufactured under license
from Dolby Laboratories.
Model Nine GX 3

SYSTEM
CONNECTION
DIAGRAM
FM
OUTDOOR
FM
INDOOR
ANTENNA
AM
OUTDOOR
ANTENNA
DIRECTION
OF
ANTENNA
FM
Staton
Note: If the 75-ohm antenna terminals are
used, the 300-ohm ones should not
be used, and vice-versa.
ACIZOV~ /220V- 240V-V80/6 0H
o (m0 e)
SWITCHED UNSWITCHED
TOTAL 200W MAX 200W MAX
a = =
= =
A+B A+C, or A+B+C; B~ 162
SOyS4P 758
: See page 18.
To AC Outlet
Ox:
To Bor C
terminals
34IM GNNOUS
oe
= Right
TURNTABLE
A
TAPE
DECK
A
SPEAKER
SYSTEMS
SPEAKER
SYSTEMS
4 = Model Nine GX

SYSTEM CONNECTIONS
1. One Pair of Speakers
The speakers should be connected to the A
terminals. Only the corresponding speaker A
button on the front panel should then be pushed
to activate these speakers.
2. Two Pairs of Speakers
Connect the two pairs of speakers to the A and B
speaker terminals. Push A button for A and B
button for B speaker system response. Push both
A and B buttons in if you wish to have speaker
response from both systems.
Note: © —————— SSS
No response will be obtained if both B and C buttons are
pushed in when only one speaker is thus connected.
3. Three Pairs of Speakers
Connect the three pairs of speakers to the A, B
and C speaker terminals.
Push in only the corresponding button of the
speaker system from which response is desired.
Note:
If three pairs of speakers are used at the same time, a
speaker system must have an impedance of 8 ohms or more.
It is recommended that the tips of the speaker
cord leads be soldered, or the strands of individual
leads be twisted together to eliminate any
possibility of short-ircuit in the speaker connecting
network. Refer to the figure below.
{Omm
=== a Remove insulation
from wire end.
mo Twist stranded wire.
SPEAKER LEAD WIRES
Loosen the Insert the Tighten the
screw wire screw
Correct Speaker Phasing
When connecting speakers to the speaker ter-
minals of the unit, be sure that the polarity of the
speakers and the unit terminals correspond
properly; that is, connect the positive terminal
marked (++) of the speaker to the positive terminal
of the unit, and the negative terminal marked (—)
of the speaker to the negative terminal of the unit.
Speakers so connected to the unit terminals
provide proper bass response in sound reproduc-
tion, see Fig. A.
Improper speaker connection, see Fig. B, gives
poor bass response in sound reproduction.
Connected in this way, the bass speaker cones are
moved in oposite directions reducing bass
response.
Model Nine GX
5

SYSTEM CONNECTIONS
FM ANTENNAS
Since FM broadcast signals travel along a straight
and direct-line path, they become rather weak
behind hills and buildings even in the vicinity of a
transmitting station. FM signals also become
weak in areas distant from a station even though
there may not be any obstruction to the direct-line
path of the signal. Therefore, a good FM antenna
should be installed in the most effective manner
for the best possible FM reception.
Mountain
a
Weakened
Signal
“ A li
of Gellected Hall MT 1
Strong
Signal
ave
DIRECT WAVE AND REFLECTED WAVE
FM Indoor Antenna
In areas close to the transmitting station, the
supplied T-type antenna may suffice. Spread two
arms of the antenna horizontally and position
them for the best reception.- listening to an FM
station. The antenna can then be taped to a wall
or ceiling and must not be rounded nor folded. It
should be remembered, however, that the pickup
of reflections (similar to “ghosts” on TV) will result
in poor stereo reception. These reflections must
be reduced to a minimum, either by careful
orientation of the T-type antenna or, if this will not
eliminate them, by using a more directional
outdoor antenna.
FM T-TYPE ANTENNA
TWIN LEAD (3002) CONNECTION
6 Model Nine GX
FM Outdoor Antenna
In areas at a greater distance from the
transmitting station, the use of an outdoor
antenna is highly recommended. It is available in
various types. For reception of stations located in
many directions, a non-directional type antenna
will offer better results. When using a directional
antenna, always orient it for the best reception of
the desired station. The correct position will be
indicated by maximum deflection of the SIGNAL
meter on the unit.
If a coaxial FM antenna cable (75 ohms) is to be
connected, the connection is shown as follows.
Fold back the
Shield net wire.
Strip the coaxial cable as shown in (A).
Loosen the screws and connect the cable as shown in (B).
Then tighten all screws for a connection like (C).
COAXIAL CALBE (752) CONNECTION
AM ANTENNAS
The AM ferrite bar antenna incorporated in this
receiver assures satisfactory reception of all local
AM stations. Since the ferrite bar antenna has
directional purposes, you should adjust the anten-
na to the position which brings in the strongest
signal.
In fringe areas or in locations surrounded by steel
frame buildings where satisfactory reception
cannot be obtained with the ferrite bar antenna,
an AM outdoor antenna should be connected to
the AM terminal.
Note:
To prevent any possible radio interference, keep AC power
cords
and
speaker
leads
away
as
far
as
possible
from
the
AM ferrite bar antenna.

SYSTEM CONNECTIONS
TURNTABLES
The two shielded audio cables from your stereo
turntable should be connected to the phono input
plugs. Connect the left channel of the turntable to
the PHONO 1 [L] input jack, and the right channel
to the PHONO 1 [R] input jack.
If an additional turntable is used in order to
operate two turntables, connect the left channel to
the PHONO 2 [L] input jack, and the right channel
to the PHONO 2 [R] input jack.
And either case, you should not forget to connect
the grounding wire to the receiver's GND terminal
to eliminate hum noise.
TAPE DECKS
Recording
A tape deck can be connected for recording as
follows. Left channel input of the tape deck to the
TAPE A REC [L] jack. Right channel input of the
tape deck to the TAPE A REC [R] jack.
Playback
A tape deck can be connected for playback as
follows. Left channel output of the tape deck to
the TAPE A PLAY [L] jack. Right channel output
of the tape deck to the TAPE A PLAY [R] jack.
DIN
CONNECTOR
(REC/PLAY)
If your tape deck is equipped with a DIN connec-
tor, connect it to the REC/PLAY connector with a
DIN cord. The DIN connector enables recording
and playback with this single cord. However,
before connecting check whether the impedances
at the DIN connecting terminals of the receiver
and the tape deck are equal. If they are not equal,
use RCA pin cords to ensure correct sound quality.
Note: © ——<— —@— SSF
When the tape deck is connected to the receiver with a DIN
cord, the TAPE B PLAY and TAPE B REC jacks should not be
used.
AUX (AUXILIARY)
High level AUX input jacks are for miscellaneous
sources, such as extra tape decks, additional
tuners and other external components.
PRE OUTPUT 4
PRE OUTPUT-POWER INPUT jacks
By utilizing these jacks and interconnecting with
other equipment as shown in Figure below, the
Model Nine GX can be used for multi-channel
system. Moreover, by simply connecting an adap-
tor to these jacks, a 4-channel reproduction can be
enjoyed.
In such a case, the bridge connecting plugs must
be removed.
Use of the multi-amplifier system is as follows.
1. Remove both of the plugs bridging the PRE
OUTPUT and POWER INPUT jacks.
2. Connect the PRE OUT jacks to the input jacks
of the crossover network.
3. Connect the POWER INPUT jacks to the out-
put jacks of the crossover network.
Note:
For detailed instructions on connections, etc., see the in-
struction manual supplied with the adaptor.
POWER AMP
POWER AMP
POWER INPUT
{(] HIGH- RANGE
CROSSOVER
NET WORK
MID-RANGE
LOW-RANGE
PRE AMP
POWER AMP
AC OUTLETS
The AC outlets on the rear panel of the receiver
may be used to supply power to other
components such as a turntable, tape deck, etc.
1. SWITCHED outlets
These outlets are controlled by the POWER
switch and the Timer on the front panel. (The
total capacity is 200 watts maximum.)
2. UNSWITCHED outlet
This outlet delivers power at all times. (The
capacity is 200 watts maximum.)
Note:
Never connect any equipment whose power consumption
exceeds the capacity of each outlet.
Model Nine GX 7

CONTROLS, INDICATORS AND CONNECTORS
[1] [2}[3] [4] [5 [6
ee mode Now GX
it} [2} [13] faa) site 17)
[1] SPEAKERS
A — Activates speakers connected to the SPEAKER A ter-
minals on the rear panel.
B — Activates speakers connected to the SPEAKER B ter-
minals on the rear panel.
C — Activates speakers connected to the SPEAKER C ter-
minals on the rear panel.
For private listening through headphones, release all the
SPEAKER buttons.
[2] POWER/LINE LEVEL switch
This push button switches the meters to read POWER out-
put or LINE signal levels. The POWER/LINE LEVEL meters
indicate the power output level when the switch is depress-
ed. When it is released, the meters indicate the line signal
level.
[3] METER range switch
This switch allows selection of meter sensitivities for
POWER output. Set the switch to either the 3W or 150W
setting in accordance with the strength of the power output.
Note:
To protect the meters from overswing, make it a rule to set
the METER range switch to the 150W position. And push it
in to the 3W position for a more sensitive reading only when
the meter can hardly be read using the 150W switch posi-
tion.
[a] SPEAKER indicator
The lamps, A, B, and C, light to show which SPEAKER
switches are engaged.
[5] POWER/LINE LEVEL meters
POWER — When the POWER/LINE LEVEL switch is
depressed, the meters indicate the power output level.
8 Model Nine GX
18} [19} [20][21] (22) [23] [2a
7} [8] 9 ].[10]
LINE LEVEL — When the POWER/LINE LEVEL switch is
released, the meters indicate the line signal strength.
In addition, the meters are to be used as Dolby CAL
level meters when the 400 Hz CAL switch is depress-
ed.
[6] SIGNAL meter
This meter indicates the strength of the AM or FM signals
received. It is used as a tuning aid for both AM and FMtun-
ing and very useful in making antenna adjustments.
TUNING meter
This meter gives a precise indication of correct FM tuning.
Maximum stereo separation and minimum distortion are Ob-
tained when the receiver is tuned to center the pointer on
the meter scale.
Indication lamps
These lamps light to show which source has been selected
by the SELECTOR switches and which mode has been
selected by the function switches.
[9] TUNING knob
AM and FM stations are tuned by turning this knob.
SELECTOR switches
AM — for reception of AM broadcasts.
FM — for reception of FM broadcasts.
PHONO 1 — Audio from a turntable connected to the
PHONO 1 input jacks.
PHONO 2 — Audio from a turntable connected to the
PHONO 2 input jacks.
AUX — Audio from a source connected to the AUX jaks.
[11] POWER switch
ON — turns the receiver on.
OFF — turns the receiver off.

CONTROLS, INDICATORS AND CONNECTORS
[12] PHONES
Insert stereo headphone plugs into these jacks.
[13] TIMER control
The model Nine GX is equipped with a TIMER control which
enables the set to be switched off automatically at any
predetermined time within two hours from the time of set-
ting. If the predetermined time is set wrong unintentionally,
for example, it has been set at 120 instead of 60, correction
can be made by turning the TIMER control counterclockwise
to the required time of 60. The TIMER control required
more force to turn counterclockwise than clockwise.
Note:§ ——@—____________»>OSsSsSsSsSSssSF
When the TIMER control is set to OFF, the AC power
remains off, regardless of the setting of the POWER switch.
Therefore, the TIMER control must be set to RESET to
operate the receiver. The AC convenience outlet on the rear
panel marked SWITCHED 200W is switched by the POWER
switch and TIMER.
TRIPLE TONE CONTROL
ON — This setting activates the BASS, MID, and TREBLE
controls.
OFF — This setting switches in a bypass circuit to provide a
linear frequency response, regardless of the tone con-
trol settings.
[15] FM MUTING switch
In the “depressed” position, muting silences interstation
noise during tuning. To receive very weak stations, stations
that are too weak to overcome the muting threshold, disable
the muting by pushing the switch to release.
FILTERS
SUBSONIC — Frequencies below 18 Hz are attenuated by
15 dB/octave. Although such subsonic frequencies
are inaudible to the human ear, they can cause, inter-
modulation distortions and even damage the
loudspeakers. It is advisable to leave the switch in at
all times, even if no record rumble, etc. is heard.
HIGH — Pressing this button in (latched) reduces signals
above 10 kHz at the rate of 6 dB per octave. Press
this button in to lessen the effects of tape hiss, record
scratches, etc. Press again to unlatch (button out) in
all other cases.
TRIPLE TONE CONTROL
BASS -— Turn clockwise to increase bass response,
counterclockwise to reduce bass response.
MID — Turn clockwise to increase mid-range response,
counterclockwise to reduce mid-range response.
TREBLE — Turn clockwise to increase treble response,
counterclockwise to reduce treble response.
LOUDNESS control
The LOUDNESS control compensates for a natural deficien-
cy in human hearing, the human ear is less sensitive to bass
notes at low volume levels. Use the LOUDNESS control to
give the best bass response at normal listening levels. In the
OFF position response is flat. Use this setting for loud
listening levels.
BALANCE control
This control permits balancing of left and right channels
when an imbalance exists in the sound source, or to correct
an acoustic imbalance due to room conditions. Turn it to the
left, from the zero position, to boost the left channel; turn it
to the right from zero to raise the level for the right channel.
MONO switch
The left and right channel signals are mixed together and
can be heard from both speakers.
[21] 400 Hz CAL switch
This is used for calibration of the record input level of a tape
deck. When the switch is depressed, the built-in oscillator
Operates and a sine wave signal is applied to the TAPE A
REC jacks. The calibration level is displayed on the
POWER/LINE LEVEL meters.
[22] VOLUME control
This control adjusts left- and right-channel volume
simultaneously. Set it for the desired listening level.
[23] NR MODE switch
OFF — This position is for operation without using the
Dolby unit.
ON — This position is for operation with using the Dolby
unit.
PLAY for playback a Dolbyized recording from an in-
coming non-Dolbyized signal.
Further details on pages 16 and 17.
TAPE MONITOR switch
Switch positions and functions are as follows.
SOURCE — The source signal is heard.
A — For monitoring a recording or for playback on a tape
deck connected to the TAPE A jacks.
B — For monitoring a recording or for playback on a tape
deck connected to the TAPE B jacks.
[25] DOLBY LEVEL control
PLAY CAL A TAPE — These knobs control the playback
outputs from a tape deck to the proper Dolby level.
REC LEVEL — These knobs control the record level of the
signals to be recorded through the Dolby unit. Adjust
the knobs so that the LINE LEVEL Meter Pointer
remains within the CAL zone of the POWER/LINE
LEVEL Meter and the tape deck’s VU meters indicate
“OVU".
MIC MIXING and MIC input
MIC MIXING permits mixing of a signal from the mono
microphone input jack with the desired source selected with
the SELECTOR switch. To activate MIC MIXING, pull the
knob and turn clockwise. When microphone sound is not
required, turn the MIC MIXING LEVEL control fully
counterclockwise and switch off by pushing in. Further
details on page 11.
Model Nine GX 9

OPERATING INSTRUCTIONS
(WITHOUT USING DOLBY UNIT)
AM-FM RECEPTION
Set the SELECTOR switch to AM or FM.
2. Set the MODE switch to STEREO (OFF) and
the TAPE MONITOR switch to SOURCE.
3. Adjust the VOLUME control to the desired
listening level.
4. Use the TRIPLE TONE CONTROLS, FILTER
and LOUDNESS controls to adjust sound as
desired and to match the acoustic conditions
of your room.
—_
TURNTABLE OPERATION
1. Two pairs of phono input jacks, PHONO 1
and PHONO 2, are provided to enable
connections to two turntables.
To reproduce the output of the turntable
connected to PHONO 1 jacks, set the
SELECTOR switch to PHONO 1. To
reproduce the output of the turntable con-
nected to PHONO 2 jacks, set the
SELECTOR switch to PHONO 2.
2. Set the MODE switch to STEREO (OFF) and
the TAPE MONITOR switch to SOURCE.
3. Use the TRIPLE TONE CONTROLS, FILTER
and LOUDNESS controls to adjust the sound
to your preference and to the acoustic con-
ditions of your room.
TAPE DECK OPERATION
Tape Monitoring
If you use the receiver with 3-head type tape
decks, you can check the sound quality of the
recording being made momentarily by comparing
the recorded signal with the source signal as
follows. Set the TAPE MONITOR switch to A (or
B) to monitor the recorded sound. Set the TAPE
MONITOR switch to SOURCE to monitor the
source signal before recording.
10 = Model Nine GX
When Recording with One Tape Deck
Connect the tape deck to either TAPE A jacks or
TAPE B jacks on the rear panel.
Recording
1. Set the SELECTOR switch to the desired
program source. Set the TAPE MONITOR
switch to SOURCE. To monitor the recording,
set the TAPE MONITOR switch to A or B,
whichever side the tape deck is connected.
2. Recording level should be adjusted with the
volume contro! of your tape deck.
3. Recording is not affected by the VOLUME,
TRIPLE TONE CONTROLS, FILTER,
LOUDNESS, etc., controls of the receiver.
When Recording with Two Tape Decks
Connect one tape deck to TAPE A jacks and the
other to TAPE B jacks on the rear panel.
Recording
1. Set the SELECTOR switch to the desired
program source.
2. Set the TAPE MONITOR switch to SOURCE.
3. Recordings can now be made into both tape
decks simultaneously. To monitor these
recordings, use the TAPE MONITOR switch
as follows. Set it to A to monitor the
recording being made with the tape deck
connected to TAPE A jacks. Set it to B to
monitor the recording being made in the tape
deck connected to TAPE B jacks.
4. Recording levels should be adjusted exactly
as mentioned above for single tape deck
operation.
Playback
1. The SELECTOR switch can be in any
position.
2. Set the TAPE MONITOR switch to the
corresponding position (A or B).
3. Adjust volume and tonal quality.

OPERATING INSTRUCTIONS
(WITHOUT USING DOLBY UNIT)
Tape-to-Tape Dubbing with THROUGH
CIRCUIT
Tape recordings may be easily duplicated from
one tape deck to the other by setting the NR
MODE switch to OFF A > B or OFF B > A as
follows:
1.
2.
3.
The SELECTOR switch can be in any
position.
Set the NR MODE switch to OFF A> B
when it is desired to copy recorded material
on the tape deck A for re-recording on the
tape deck B.
Set the NR MODE switch to OFF B® A when
_ it is desired to copy a recording on the tape
deck B for re-recording on the tape deck A.
The recording can be monitored. (If the
TAPE MONITOR switch is set to SOURCE,
SOURCE can be listened to even during the
tape-to-tape dubbing. This is thanks to the
THROUGH CIRCUIT.)
Operate both tape decks simultaneously.
MIC MIXING WITH SOURCE PROGRAM
1.
Set the NR MODE switch to the SOURCE
position and the SELECTOR switch at any
program as you desired.
Then turn on the MIC MIXING by pulling its
knob.
TAPE MONITOR positions are as follows.
SOURCE ...Source program mixed with MIC
input.
Aikgse. eet lots Playback sound of the TAPE
DECK A (source with MIC).
Bockecienicciaes Playback sound of the TAPE
DECK B (source with MIC).
2. Set the NR MODE switch to the REC-A
position and the SELECTOR switch at any
program as you desired.
Then turn on the MIC MIXING by pulling its
knob.
TAPE MONITOR positions are as follows.
SOURCE ...Source program mixed with MIC
input through the Dolby.
Ascites Playback sound of the TAPE
DECK A (Encoded source with
MIC input).
Beek sekis Playback sound of the TAPE
DECK B (source with MIC).
Switch | (BSE,
|
Model Nine GX 11 ;

OPERATING INSTRUCTIONS
(WITH USING DOLBY UNIT)
OUTLINE OF THE DOLBY NR SYSTEM
The basic principle of the Dolby NR system is as
follows. During the recording process, all low
level, high frequency source signals above
midrange — the area where noise is most
discernible — are boosted automatically with a
Dolby compressor circuit before being put on
tape. During playback, the Dolby expander circuit
automatically reduces these boosted signals to
their original levels. At the same time, the tape
noise introduced during the recording process is
also reduced by the same amount. The end result
is a Significant improvement in the signal to noise
ratio. This means that tape noise, in effect,
becomes indiscernible to the ear.
The Model Nine GX receiver boosts highest
fidelity sound reproduction thanks to built-in
Dolby NR system which processes signals from
all sound sources. This means that FM programs
can be of equivalent audio quality as those
reproduced from your “denoised” tapes.
RECEPTION OF DOLBYIZED FM
BROADCASTS
When the transmission of Dolbyized FM
broadcasts starts, the DOLBY FM switch on the
NR MODE must be selected to its position and the
DOLBY FM decoder operates so that Dolbyized
FM broadcasts are decoded and can be enjoyed.
At this time the SELECTOR can be in any
positions, the DOLBY FM switch only is necessary
for the reception of Dolbyized FM broadcasts.
SETTING THE DOLBY STANDARD LEVEL TO
RECORDING AND PLAYBACK
The purpose of the following adjustments is to
achieve the proper Dolby levels by calibrating the
recording and playback signals being applied to
the Dolby processors.
To perform this adjustment, the Standard
Alignment Tape must be played on the tape deck
(or recording system) connected to the receiver.
However, if you do not have a Standard Alignment
Tape, you can create a Dolby Alignment Tape in
the following way for Dolby recording and
playback.
TO CREATE DOLBY ALIGNMENT TAPE
1. Load a blank tape (or insert a cassette) on the
tape deck connected to the TAPE A jacks.
2. Set the 400 Hz CAL switch to ON and the
NR MODE switch to REC-A.
3. Set the tape deck’s monitor switch to its
source position and adjust the tape deck’s
input level control so that it indicates a
recording level of O VU.
4. In this condition, record the signal on the
tape for about one minute. You have now
created a Dolby Alignment Tape for the
adjustment of your system.
5. Now turn the 400 Hz CAL switch and NR
MODE switch OFF.
Please refer to the figure below.
LINE LEVEL METER
UONESS MONO = 400Hz CAL
SELECTOR
PHONO | PHONO 2
aa
12 Model Nine GX
66006
NR MODE
lice
UR
A
APLAY <A
Peary
ay C.
OovBy source t PR TABeS
i OorRe OR
NR MODE POSITION FOR CREATING DOLBY ALIGNMENT TAPE
OO @ ::.
“ON”
COLAY SYSTEM O.

OPERATING INSTRUCTIONS
(WITH USING DOLBY UNIT)
This Dolby Alignment Tape can be used to adjust
the Dolby recording characteristics of your
receiver and the tape deck or recording system
with which it will be used.
Note:,§ ————__—_
A home made Dolby Alignment Tape is a second best alter-
native to using a real Dolby Standard Alignment Tape.
However, to adjust your system more accurately to the
Dolby standard level, a Dolby Standard Alignment Tape is
available from Kenwood. Contact the following office,
specifying the model of the tape required.
Dolby Standard Alignment Tape
Model KST-11..... for Cassette Tape Deck
Model KST-12..... for Open-Reel Tape Deck
TRIO-KENWOOD CORPORATION
c/o Higashiyama Bldg. 7th floor
1-2, 1-Chome, Higashiyama
Meguro-ku, Tokyo
153 Japan
PROCEDURE FOR PLAYBACK
CALIBRATION
1.
Connect
a
tape
deck
to
the
TAPE
A
jacks.
Set
the
Dolby
NR
MODE
switch
to
A
PLAY
(A
>
B).
3. Set the POWER/LINE LEVEL switch to line
level.
4. |fthe tape deck has a monitor switch, set it to
tape play.
5. Load the Dolby Alignment Tape on the tape
deck.
6. Play the Dolby Alignment Tape.
7. If the tape deck has playback level controls,
adjust these so that the tape deck’s VU
meters indicate O VU.
8. If the tape deck does not have playback level
controls, proceed to Item 9. If it does not
have VU meter, set the level controls to
about 2/3 of their maximum.
9. Adjust the PLAY CAL controls (left and right)
so that the LINE LEVEL meters (left and
right) deflect to the Dolby CAL mark.
10. Now that Dolby Playback calibration is
complete, do not adjust the PLAY CAL
controls or the tape deck’s Playback Level
controls.
Please refer to the figure below.
LINE LEVEL METER
UDNESS MONO) 400Hz CAL
= ON
B® OFF
“OFF”
n”.CU!UC~« En SELECTOR _*"""
PHONO I “PHONO2 AL 2
O00O00°0
NR MODE ——
RR
TARE MON 4
| SOURCE
Ae Be ® » Bea
A PLAY
oz ef
{A-B) B, REC
” PLay cat !
DOLBY] T: - a—t SOURCE ! e
EM. I |
5 5
=
OF
|
ie
ie
REC LEVEL
NR MODE POSITION FOR PLAYBACK CALIBRATION
Model Nine GX 13

OPERATING INSTRUCTIONS
(WITH USING DOLBY UNIT)
It will be necessary to re-calibrate the Dolby levels
as described in the following manners:
1. When using tapes of different types
(Standard, Low-Noise, CrO2 etc.).
2. When changing over the setting of the tape
deck. Otherwise, the controls will be set
incorrectly. To avoid making mistakes after
having set the controls, mark their positions
with ribbon tape after making the
adjustment.
PROCEDURE FOR RECORD CALIBRATION
Without having calibrated the playback system,
the recording system cannot be cablibrated, so
first calibrate the playback system. As_ for
playback calibration, calibrate the recording
system with a tape loaded on the tape deck
connected to the TAPE A jacks.
Tape Decks
1. Load a blank tape or insert a cassette in the
tape deck.
Set the NR MODE switch to REC-A.
Set the 400 Hz CAL switch to ON.
Set the tape deck to the recording mode.
Adjust the tape deck’s input level controls so
that the tape deck’s VU meters indicate O
VU.
6. Now record the signal on the tape for about
15 seconds.
7. Set the 400 Hz CAL switch OFF and stop
the tape deck, rewind the tape.
8. Set the Dolby NR MODE switch to A PLAY
(A> B) and the POWER/LINE LEVEL switch
to LINE LEVEL.
9. Set the tape deck to playback.
10. Observing the right and left Level Meters, see
if they deflect to the Dolby CAL Mark. If they
do, the calibration is correct.
11. If the Level meters do not deflect to the
Dolby CAL Mark, repeat adjustments of the
tape deck’s recording level controls so that
the receiver's VU meters deflect to the Dolby
CAL Mark. At this time, do not adjust the
tape deck’s playback level controls.
OWN
14 Model Nine GX
Tape Decks of which Record and Playback
Level Controls are the Same
This type of tape deck is such that one control
must be used to calibrate the recording and
playback levels. After calibrating the recording
(playback) level, mark the position of the knob.
Then perform the adjustment of the playback
(recording) system with reference to the marked
position. Apart from this, calibrate in the same
way as with a two-head deck.
TAPE MON
A
SELECTOR
Switch
—§
REC PLAY REC PLAY
A B
NR MODE POSITION @

OPERATING INSTRUCTIONS
(WITH USING DOLBY UNIT)
This concludes the adjustment portion. For
recording and playback, perform the following
procedure:
Dolbyized Recording from an Incoming ‘Flat’
(Non-Dolbyized) Signal
1. Connect a tape deck to the TAPE A jacks and
set the controls to the positions determined
in CALIBRATION.
2. Set the SELECTOR switch to correspond to
the input from which you are to record (AM,
FM, PHONO, AUX, MIC or Tape B).
3. Set the NR MODE switch to REC-A or REC-B
PA.
4. Adjust the REC level controls so that the level
meter deflection is correct (around O dB). At
this time, do not adjust the tape deck’s Input
and Output Level Controls.
All adjustments should be with the REC level
control.
5. Set the tape deck to the recording mode.
400Hz
© REC
OPER ace). REVEL
TAPE MON
A
REC PLAY REC PLAY
A 8
NR MODE POSITION ©, @
Recording Dolbyized FM Broadcasts
If the receiver has been calibrated to make
Dolbyized recordings, set the NR MODE switch on
its DOLBY FM position to make Dolbyized
recordings, adjusting the recording level with the
recording
level
controls
on
the
tape
deck.
After decoding, a flat signal can be recorded on
Tape B.
To Play Back Dolby Tape
1. If the tape deck connected to the TAPE A
jacks has not been calibrated, do this. (See
page 13 “PLAYBACK CALIBRATION”)
Set the TAPE MON switch to A.
Set the NR MODE switch to A PLAY (A > B).
Playback using the tape deck. At this time, if
there is a tape deck connected to the TAPE B
jacks in the normal way, decoded signals
with a flat frequency characteristic can be
recorded.
ON
Dubbing Dolby Encoded Tape from Tape A to
Tape B
Dubbing is done by using the NR MODE switch.
When recording on the deck connected to the.
TAPE B jacks from the deck connected to the
TAPE A jacks, calibrated by adjusting their output
level controls in conjunction with each other.
(‘DOLBY NR MODE CHART” is furnished on
pages 16 and 17 for your ready reference.)
Model Nine GX 15

DOLBY NR MODE CHART
NR MODE
eee
SOURCE
Ar B Brea
@2 6
BLOCK DIAGRAM
Bold line shows
encorded signal
DOLBY FM
This position is designed for only the DOLBY FM
broadcasts.
And the recording of Dolby FM programs are
available to TAPE A and B.
TAPE A Encoded signal
TAPE B Decoded signal
The positions of TAPE MON switch are as follows.
SOURCE ...Decoded Dolby FM
Monitor the recording of TAPE A
(Encoded)
Monitor the recording of TAPE B
(Decoded)
The Dolbyized tape of the TAPE DECK A can be
played back and copied.
The positions of TAPE MON switch are as follows.
SOURCE ...Playback sound of the Dolbyized tape
Sound before passing through the
Dolby circuit
Copied sound
Selector [PLay
Switch 1 CA
The signal does not pass through the Dolby circuit
with the switch set to this position.
The positions of TAPE MON switch are as follows.
SOURCE ...Sound selected by the SELECTOR
switch can be listened to while
dubbing from A to B at SOURCE.
Playback sound of the TAPE DECK A
Playback sound of the TAPE DECK B
16 Model Nine GX
When the Dolby circuit or the dubbing circuit is
not used, set the switch to this position (usual
position).

DOLBY NR MODE CHART
The signal does not pass through the Dolby circuit
with the switch set to this position.
The positions of TAPE MON switch are as follows:
SOURCE ...Sound selected by the SELECTOR
switch can be listened to while
dubbing from B to A at SOURCE.
Playback sound of the TAPE DECK A
Playback sound of the TAPE DECK B
When modifying the Non-Dolbyized tape to the
Dolbyized tape, set the switch to this position.
The played back signal on the TAPE DECK B
passes through the Dolby circuit, to be recorded
on the TAPE DECK A.
When recording through the Dolby circuit, set the
switch to this position.
The positions of TAPE MON switch are as follows.
SOURCE...Sound selected by the SELECTOR
switch can be listened to.
Encoded sound on the tape A can be
monitored.
Recorded sound on the tape B can be
monitored.
The tape A is the only tape that can be Dolby-recorded.
CAUTION
If the receiver's built-in Dolby system is to be used, adaptors to improve sound reproduction (Reverberation unit, Dynamic ex-
pander, Graphic equalizer, Active equalizer etc.) should be connected to the PRE OUTPUT and POWER INPUT jacks. If the
adaptors are connected to the TAPE jacks, the Dolby system should not be used since this will spoil the Dolby effect.
Be sure to turn off the AC POWER switch before connecting adaptors to the PRE OUTPUT and POWER INPUT jacks.
Model Nine GX 17

BLOCK DIAGRAM
Block Diagram
S1 INPUT SELECTOR
\j7 $2. NR MODE
$3. TAPE MONITOR
$4 400 Hz CAL
S5 MODE
S6 LOUDNESS
$7 TRIPLE TONE
CONTROL ON
$8 METER SELECTOR
$9 SPEAKERS
$10 FM MUTING
$11. POWER RANGE
SIGNAL TUNING
1
1]
il
:
'€
|
f
I
FERRITE
BAR
ANTENNA
2
Ke
x3
3
TRIPLE
()
$4
TONE
PRE
OUT©@)
©POWER
IN
Pre-amp
DOLBY{UNIT
20dB
amp
CONTROL
POWER
amp
PHONO
1
53
$5
QZ)
A
tho
SLRS
>
#4
Lam
aC
SIRS
LITHAS
Re
US)
4
VUU
a
CO—@
B
PHONO
2©
S2
=a
BALANCE
PUY
|
QP)
c
FM
pF
|
SUBSONIC/HIGH
DOLBY
VO|LUME
6)
__|
FILTER
4
S6
xs
STIQS)
PHONES
AUX
©
© ©
S7
Bal
1
MIC amp
sa TAPE
mic® ee £ Ese5 | PHONES
—<— | vk Lever
FM DE-EMPHASIS SWITCH
Prior to our shipment, this switch is set as below
in accordance with the delivery area. Check the
setting position before operating the unit. Im-
proper setting will adversely affect the high fre-
quency range.
Europe, Oceania and South Africa........ 50us
OTH OTS iii dasadedeeoia eel lem sciecaea Maceee Seune 75us
NOTE:
As for the Dolby FM, Set the NR MODE switch to DOLBY
FM so that the de-emphasis of “25us” has an effect on
Dolbyized FM programs, regardiess of either 50us or 75us
position at the rear pannel.
18 Model Nine Gx

SPECIFICATIONS
POWER AMPLIFIER SECTION
Power Output
80 watts per channel minimum RMS, both
channels driven, at 8 ohms from 20 to 20,000
Hz with no more than O
distortion.
Both Channels Driven ..................
Dynamic Power Output................
Total Harmonic Distortion............
Intermoduration Distortion...........
(60 Hz: 7kHz = 4: 1)
Power Bandwidth .....................5.
Frequency Response
Signal to Noise Ratio ...................
Damping Factor..................
Input Sensitivity/Impedance ..
Speaker Impedance .....................
.03% total harmonic
110 + 110W 40 at 1 kHz
280W 40
0.03% at rated power into 82
0.01% at 1/2 rated power into
8
0.03% at rated power into 82
0.01% at 1/2 rated power into
82
5 Hz to 100,000 Hz
5 Hz to 100,000 Hz — 1.5 dB
115 dB (short circuited)
... 40 at 8 ohms
... 1,.0V/50 kQ
Accept 40 to 162
PRE AMPLIFIER SECTION
Input Sensitivity/Impedance/Signal to Noise Ratio (IHF A curve)
PRON sss cc soccnceckcsavedeaaveeseess
Maximum Input Level for Phono...
Frequency Response
AUX and Tape..........0..... cee
Tone Control
BASS eicceccciiieecccestestiyectfelivascer
Midivccn. den auans aitneiuue.
TrODIG?® sis ladiici ones taans
Loudness Control (— 30 dB Vol.)...
Subsonic Filter .................008
High Filter 0.000... eee
Output Level/Impedance
Tape REC (Pin) ............0..0000.
Pre Outicc csi hele
2.5 mV/50 kQ/80 dB
2.5 mV/50 kQ/80 dB
150 mV/50 kQ/110 dB
150 mV/50 kQ/110 dB
1.5 mV/10 kQ/70 dB
230 mV (RMS), T.H.D. 0.03%
at 1,000 Hz
RIAA standard 30 Hz to 20 kHz
+0.3 dB
10 Hz to 40,000 Hz — 1.0 dB
+12 dB at 50 Hz
+12 dB at 800Hz
+12 dB at 15 kHz
+10 dB at 100 Hz
—15 dB at 18 Hz
—6 dB at 10 kHz
A: 1580 mVv/1002
B: 150 mV/100Q
A: 30 mV/80 ko
B :120 mV/80 kQ
1.0V/1 kQ
FM TUNER SECTION
Usable Sensitivity ..............00..0.0. 10.3 dBf (1.8 nV)
50 dB Quieting Sensitivity
14.7 dBf (3.0 nV)
37.2 dBf (40 nV)
Frequency Response.................... 30 Hz to 15,000 Hz + 0,5,
—1,.0dB
Capture Ratio ....................000000. 1.0dB
Alternate Channel Selectivity ....... 75 dB
Spurious Response Ratio ............. 85 dB
Image Response Ratio ................. 60 dB
IF Response Ratio........................ 75 dB
AM Suppression Ratio at
G5dBE sleigh faceted: 65 dB
Stereo Separation........................ 48 dB at 1,000 Hz
35 dB at 50 Hz to 15,000 Hz
Sub Carrier Product Rejection ...... 46 dB
Antenna Impedance..................... 3002 balanced and 752
unbalanced
FM Frequency Range ................... 88 MHz to 108 MHz
AM TUNER SECTION
Usable Sensitivity ....................... 20 nV
Signal to Noise Ratio ................... 50 dB
Image Rejection... 55 dB
Selectivity... ees 30 dB
IF Rejection ......0.00..... eee 30 dB
Total Harmonic Distortion............ 0.5%
GENERAL
Power Requirement ..................... 50/60 Hz, 110-120/
220-240V
Power Consumption .................... 550 watts at full power
A.C. Outlet 0... eceeeeee Switched 2, Unswitched 1.
Dimensions W..............0000008. 624 mm__,{24-9/16")
He casigitasevsacsseeiints 206 mm__(8-1/8")
Di ticareeatead 460 mm__(18-1/8")
Weight. i0..0i5 2c. lied ceicescies 19.8 kg (43.5 Ib)
(Gross)........ cece 24.3 kg (53.6 Ib)
NOTE:
Kenwood follows a policy of continuous advancements in develop-
ment. For this reason specifications may be changed without
notice.
Model Nine GX 19