Marantz 4300 User manual

: .:~
Model 4300
Stereo 2+Quadradial4
..... • .. ~~R.~ Receiver
MARANTZ CO., INC. ·P.O. BOX 99'SUN VALLEY, CALIFORNIA·91352
AWHOLLY-OWNED SUBSIDIARY
OF SUPERSCOPE INC., SUN VALLEY, CALIFORNIA 91352

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TABLE OF CONTENTS
External Decorder Connection 13
ITape Recording 13
Power Connections 13
Connecting the
4300
2AC Protector
Fuse
13
ISource Device 4
Remote Speakers 4
Basic Dolby Process
ISpeaker Phasing 5
Speaker Placement 5Dolby Calibration 14
Procedure
for Playback Calibration 14
Front
Panel Features 7Procedure
for Record Calibration 15
IMode Switch 7
Use of the Dolby System on FM
Dimension 8Broadcasts 16
SO Decoder 8
FM De-Emphasis Switch 16
IBalance Controls 8Explanation
of the Dolby Mode Chart 16
Selector Switch 8
Bass, Mid and Treble Controls 8Technical Description 18
IMon
itor Switch 8General 18
Main and Remote Spkr Switches 9
Power Switch 9Functional Description 18
IFront and Rear
Phones Jacks 9
Front End 18
Loudness Switch 9IF
Stages
18
Low Filter Switch 9
Limiter
18
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Hi Filter Switch 9FM Stereo Demodulator 18
Meters 9Muting Circuit 18
Tuning 9
AM Tuner 18
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FM Muting Switch 10 Phono Amplifiers 19
Volume 10 Selector Switch 19
Dolby Switch 10
Monitor Switch 19
Record Level
(Ll (R) 10 Tone Control 19
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Play Cal. (L) (R) 10 Power
Amplifier 19
400Hz Tone Switch 10 Driver
Stage 19
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Rear Panel Features
11
General Requirements 19
Phono Jacks
11
Installation of Walnut Cabinet
20
CD-4/AUX Jacks
11
Service Notes 20
ITape
Monitor In and Tape Monitor
Out Jacks 11
FM Antenna Terminals
11
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AM Antenna Terminal 11
FM Ouadradial Output Jack 12
FM De-Emphasis Switch 12
IDolby FM Preset Level Controls 12
Muting
Level Control 12
Power Mode Switch 12
Pre Out, Main In Jacks 12
Connecting
an External Amplifier
for Rear Channels 12
Connecting
an External Amplifier
for Front Channels 12
Chassis Ground Binding Post 12
Main and Remote Speakers 12
Connection
to AC Outlet 13
AC Convenience Outlets 13
Remote Control 13

LIST OF ILLUSTRATIONS
1. Rear Panel Connection
Facilities and Adjustments 2
2. Loudspeaker System Connections 3
3. Connection Diagram 4
4. Speaker Placement 6
5. Mono Mode Sound Dispersion 7
6. 2-channel Mode Sound Dispersion 7
7. Discrete Mode Sound Dispersion 7
8. Vari-Matrix Mode Sound Dispersion 7
9. Front Panel Controls and Jacks 8
10. Stereophone Plug 9
11. F M/ AM Antenna Connections 11
12. AM Ferrite-rod Antenna 11
13. Quick-Connect Speaker Terminal 13
14. Block Diagram 17
15. Packing Instructions 20
The
FM multiplex circuitry includes a phase
locked loop, Stereo-Monaural Automatic switch-
ing circuit, stereo indicator
circuit and abuffer
amplifier
to obtain output power at low im-
pedance. Low pass filters for 19KHz and 38KHz
rejection
are incorporated. Moreover, the Model
4300
unit has amuting circuit that permits pleas-
ant FM broadcast reception by completely elimi-
nating inter-station interference which
is usually
generated at the time
of selecting FM stations.
FOREWORD
TABLE
1. Dolby Mode Chart
16
To obtain optimum performance and enjoyment
from the Model 4300,
please study these instruc-
tions carefully.
Follow the step-by-step instruc-
tions
to obtain maximum performance.
This manual
is divided into two parts. The first
covers installation and operation in simple, non-
technical
language. The second describes the
Model 4300 in more detail
with technical specifi-
cations
and functional explanations.
GENERAL DESCRIPTION
Your Marantz Model 4300 is ahigh-quality Stereo
2+Quadradial 4Receiver developed by Marantz,
a
name famous for quality in the audio com-
ponent industry. The Model 4300 incorporates
Marantz' exclusive Vari- Matrix circuit which
sim-
ulates 4-channel sound from normal 2-channel
stereo programs, and
is capable of reproducing
4-channel sound
from any matrix-encoded source.
The 4300 will
also reproduce any discrete 4-
channel program as well as regular stereo and
monaural programs. An optional plug-in decoder
adapts the 4300
for any specific matrix system,
such as Columbia's SQ.
The FM tuner section employs an FET for the
RF amp stage. The IF tuning circuit employs
ceramic filters
of wide bandwidth and high
selectivity
to provide high sensitivity and un-
paralleled interference-free operation.
The 4300 incorporates afull-process, 2-channel
DOLBY System
to reduce noise, inherent in
recording music
from records, tape, FM broad-
casts and TV.
For quick identification
of the controls and
connections, references are printed in bold face
type.
AFTER UNPACKING
It is advisable to save all original packing material
to prevent damage should you wish to transport
or ship the Receiver (refer
to Figure 15 for pack-
ing instructions).
Please inspect your Model 4300
carefully
for any signs of damage in transit.
It has undergone stringent quality control inspec-
tion and tests prior to packing, and left the
factory in perfect operating condition.
If the
unit is damaged, notify the carrier without delay.
Only the consignee may institute aclaim
with
the carrier for damage during shipment. How-
ever, the Marantz Company will co-operate fully
in such an event. Save the damaged carton as
evidence for inspection by the carrier.

Figure 1. Rear Panel Connection Facilities and Adjustments
3. Using shielded audio cables with phono plugs,
connect your record player
to the 4300 as
follows:
CAUTION: When using the 4300 in the 100Wx2
mode, do not
use 4Ohm speakers-
use 8Ohms or higher.
to PHONO L
to PHONO R
4300
to MAIN SPEAKERS
REAR R-
to MAIN SPEAKERS
REAR R+
4300
to FRONT CD·4/AUX R
to REAR CD-4/AUX R
to REAR CD·4/AUX l
2
to FRONT CD-4/AUX L
4300
RIGHT-REAR or RR or
CHANNEL 4orTRACK 4
lEFT·REAR
or lR or
CHANNEL 2orTRACK 2
RIGHT·FRONT or RF or
CHANNEL 3 or TRACK 3
lEFT-FRONT or LF or
CHANNEL 1orTRACK 1
DISCRETE 4-CHANNEl
PLAYBACK DEVICE
lEFT OUTPUT
RIGHT OUTPUT
RECORD PLAYER
4. If adiscrete 4-channel playback device {Q-8
cartridge player, 4-channel reel-to-reel player,
CD-4 discrete disc demodulator, etc.l,
is to be
engaged in the system, make connections be-
tween the device and the 4300 using shielded
audio cables with phono plugs.
RIGHT REAR SPEAKER
- or GND or NEG or
COMM orO
+ or HOT or POS or 1
lEFT FRONT SPEAKER 4300
- or GND or NEG or
COMM or 0
to MAIN SPEAKERS
FRONT l-
+ or HOT or pas or 1
to MAIN SPEAKERS
FRONT l+
RIGHT FRONT SPEAKER
4300
- or GND or NEG or
COMM or 0
to MAIN SPEAKERS
FRONT R-
+ or HOT or pas or 1 to MAIN SPEAKERS
FRONT R+
lEFT REAR SPEAKER
4300
- or GND or NEG or
COMM or 0
to MAIN SPEAKERS
REAR L-
+ or HOT or pas or 1 to MAIN SPEAKERS
REAR L+
1. Using abalanced and shielded 300 Ohm cable,
connect
an FM antenna to the 4300 as shown
in Figure 11.
2. Using No. 18, or heavier, lamp cord (zip cord),
connect main
speakers to the 4300 as follows:
The 4300
can be used as astereo or 4-channel
Receiver. When using the 4300 as astereo unit,
the
POWER MODE Switch on the rear panel
should be placed in the 100W x 2 mode. The
instructions contained in this manual
are to be
followed for both stereo or 4-channel operation;
however,
for stereo operation, the front channels
alone will apply.
CONNECTING THE 4300
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MAil SI(AI(8l SYSTEM
Ilff'£AT WIIHG
AS FOR FfOIIY ~ SYSTtM
Figure 2. Loudspeaker System Connections
5. Using shielded audio cables with phono plugs,
connect adiscrete 4-channel tape recorder
to
the 4300 as follows:
RIGHT-REAR INPUT
or LINE IN
to REAR TAPE MONI·
TOR OUT R
DISCRETE 4-CHANNEL
TAPE RECORDER
4300
6. Pull the AM ferrite-rod antenna out as shown
in Figure 12.
7. Set the controls and switches as f.ollows:
FRONT L·R BALANCE Mid position
REAR L-R BALANCE Mid position
FRONT·REAR BALANCE Mid position
MODE VARI·MATRIX
DIMENSION Mid position
BASS and TREBLE Controls Mid position
VOLUME Minimum (fully counter·
clockwise)
LEFT·FRONT OUTPUT
or LINE OUT
lEFT-REAR OUTPUT
or LINE OUT
RIGHT-FRONT OUTPUT
or LINE OUT
RIGHT-REAR OUTPUT
or LINE OUT
lEFT·FRONT INPUT
or LINE IN
to FRONT TAPE MONI-
TOR IN L
to REAR TAPE MONI·
TOR IN L
to FRONT TAPE MONI·
TOR IN R
to REAR TAPE MONI-
TOR IN R
to FRONT TAPE MONI·
TOR OUT L
MAIN SPKR
REMOTE SPKR
FM MUTING
MONITOR (TAPE/SOURCE)
LOW FILTOR
HI FILTER
LOUDNESS
DOLBY
400Hz TONE
POWER
ON (in)
OFF (out)
ON (in)
SOURCE
OFF (out)
OFF (out)
OFF (out)
OFF
OFF (out)
OFF (out)
LEFT·REAR INPUT
or LINE IN
RIGHT·FRONT INPUT
or LINE IN
3
to REAR TAPE MONI·
TOR OUT L
to FRONT TAPE MONI·
TOR OUT R
8. Plug the 4300 into the AC wall outlet.
9. Turn the POWER Switch ON.
10. Select the desired program source
by setting
the SELECTOR Switch
to appropriate posi-
tion.

SOURCE DEVICES
00
FIlOIIT
LEfT
FIlONT
lUG"'
NOTE: Do not use ~Ohm speakers if main and
remote speakers are
to be used simulta-
neously. Use
8- or 16-Ohm speakers only.
REMOTE SPEAKERS
ourl'\lT
The 4300 can accommodate both main and
remote speaker systems. Asecond group
of
four speakers may be set up in another room.
Connect these four remote speakers
to the RE-
MOTE SPEAKERS terminals as you did the
main speakers.
The
MAIN and REMOTE SPKR Switches on the
front panel now permit activation of MAl Nand!
or REMOTE groups of loudspeakers.
4-ehannel
Discrete 4-channel playback devices (0-8 cartridge
player, 4-channel reel-to-reel player, CD-4 discrete
disc demoduiator, etc.) may be connected
to the
CD4!AUX, TAPE MONITOR 1 or TAPE MONI·
TOR 2
input jacks.
REAR
LEFT
...... _--~~~
REAlI
LEFT
RUR
RIGHT
FIlOIIT
JUGHT
R!AR
LEFT
REAR
'''CHT
FRONT
LEfT "'f--"""""-'
FAOHT
LEFT r--";",,.,
F"""T
RIGHT
1 •• 11 •• 1
000000
'f'~!"'.~ . -, . ~ .t.:n.~.· .. ~.'
.')- .~., • >< to. I
2-ehannel
Astereo record player may be connected
to the
PHONO jacks.
High level 2-channel playback devices (tuner,
tape player, record player with equalized high
level output, etc.) may be connected to the
FRONT TAPE MONITOR and CD-4!AUX IN-
PUTS.
The remainder of this manual explains how to use
your system most effectively.
11.
If phono is selected, put on astereo record.
If FM is selected, tune to astereo broadcast.
12. Increase
the VOLUME control to a comfort~
able listening level.
Your complete 4-ehannel
or stereo system is now
operative, and you may experiment with
the vari-
ous controls
to discover their effects.
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Figure 3. Connection Diagram
4

SPEAKER PHASING
To assure the best 4-channel or Stereo separation
and frequency response,
the following tests will
verify
that all four speakers are correctly phased.
1. After the speakers are connected to the 4300,
place all four speakers in the center of the
room.
2. Set MODE Switch
at MONO. Play arecord
(or radio
or tape) with strong bass tones, at a
low volume level. Center
the FRONT L-R
and REAR L-R BALANCE controls. Set
FRONT-REAR BALANCE control at extreme
FRONT position.
3. Position the front (left and right) speakers
about six inches apart, face-to-face. Listen,
particularly
to the apparent loudness of the
bass tones.
4. Next, turn off all power,
but do not disturb
the volume,
tone or balance settings. Reverse
connections on the right-front speaker only.
Turn on
the power, and listen again. If the
bass tones now seem louder than in (3), you
have corrected
the phasing between the front
(left and right) speakers. If the bass tones
now sound softer, then turn
off all power and
re-connect
the right-front speaker as you first
had it connected.
5. Now check phasing between the two left (front
and rear) speakers.
Set both FRONT L-R and
REAR L-R BALANCE controls
at extreme L
position, and set FRONT-REAR BALANCE for
equal loudness from
the two speakers. Posi-
tion
the two speakers face-to-face, about six
inches apart, and listen for bass as
in (3).
'. ,~ ~
6. Turn off power. Experimentally reverse con-
nections only on
the left-rear speaker. Use the
connection which gives the "best" bass, as
in (4).
7. Last, check phasing between
the two rear
(left and right) speakers. Center both FRONT
and REAR BALANCE controls.
Set FRONT-
REAR BALANCE control
at extreme REAR
position. Position
the two rear speakers face-
to-face as before. Listen for bass.
8. Turn off power. Experimentally reverse con-
nections only on
the right-rear speaker. Listen
again
to determine the "best" bass method of
connecting the right-rear speaker. All speakers
will then be in phase, and you may use all
controls normally.
9. Once having phased
your four speakers, you
need
not repeat the procedure in the future if
you now code
the speaker connections and/or
the speaker cables. Any method of coding is
satisfactory, provided it enables you, in the
future, to duplicate your now-correct hookup
between speakers and amplifiers.
SPEAKER PLACEMENT
Experimentation will reveal
the best speaker
locations in
your room. The placements are
shown in Figure 4.

•
RR
RR
•
R~
LR
•
RR
•
RR
•
RF
•
Figure 4. Speaker Placement
6

FRONT PANEL FEATURES
MODE SWITCH
MONO
When the MODE Switch is in the MONO position,
all input
signals are summed. Speakers are driven
as shown in Figure 5.
Use the MONO position for A) phasing speakers
and B) playing amonaural source, such as TV
audio, AM radio or monaural records through
all four channels, C) setting up
BALANCE
controls.
2CH
When the MODE Switch is in the 2 CH position,
left-front
and left-rear inputs are summed. Right-
front and right-rear inputs are summed. Speak-
ers are driven as shown in Figure 6.
Use the 2 CH position for playing regular stereo
records
without synthesizing rear channels.
DISCRETE
When the MODE Switch is in the DISCRETE
position,
each input signal goes to its respective
output channel.
Speakers are driven as shown
in Figure
7.
Use the DISCRETE position for A) playing dis-
crete 4-channel sources such as 0-8 cartridges or
CD-4 records, and B) playing 2-channel stereo
programs through
front speakers only.
VARI-MATRIX
When the MODE Switch is in the VARI·MATRIX
position, rear input signals are internally discon-
nected. Left-front
and right-front inputs feed
left-front and right-front
speakers, as in the D IS-
CR ETE MOD E. Rear channel signals are "syn-
thesized" or derived from the left-front and
right-front
input signals. The characteristics of the
; ",:.
RIGHT FRONT
SPEAKER
llWUT .OHAL DEaMlNATlONI:
L~UPT 'ftONt~ RF-IlIIOftT 'fWflIT
LII'-L&" "EAA, Rtt-fUOHT AfAlIt
Figure 5. Mono Mode Sound Dispersion
rear channel signals are varied by the DIMENSION
control. Speakers
are driven as shown in Figure 8.
LEFT REAR RIGHT REAR
SPEAKER SPEAKER
'NI'VT SleMA .. 0IW10fli&A.T10N1:
LP-L,lfT '''ONT. "'-ft'a.iT '''ONT
LR-LI!" .. !.Aft, .. " .... tGHT IlIEAlit
Figure 6. 2- channel Mode Sound Dispersion
Figure 7. Discrete Mode Sound Dispersion
LEFT FRONT RIGHT FRONT
SPEAKER SPEAKER
INPUT SIGNAL oeIlONA~;
Lf-un '''ONT, R,."tQHT fROflIT
L ... un "1M, " ...... 'aHT "£A"
Figure 8. Vari·Matrix Mode Sound Dispersion

Figure 9. Front Panel Controls and Jacks
DIMENSION
The DIMENSION control
is operative only when
the MODE Switch
is set to the VARI-MATRIX
position. This control optimizes the 4-channel
VARI-MATRIX effect.
sa DECODER
With the MODE Switch on
SO DECODER, any
rear input signals to the 4300 are internally dis-
connected. The rear channel outputs are, in-
stead, derived from front channel signals which
have been processed by the plug-in decoder. The
characteristics
of these derived rear channel out-
puts are determined by the type of plug-in
decoder.
Use saDECODER position only with an optional
plug-in decoder installed. Without this optional
decoder, there will
be no output when the MODE
Switch
is on saDECODER.
BALANCE CONTROLS
The Model 4300
has three BALANCE Controls:
FRONT L-R, REAR L-R
and FRONT-REAR.
The FRONT
L-R slide knob adjusts the balance
between the
front channels. The REAR L·R
slide knob adjusts the balance between the rear
channels. The FRONT·REAR slide knob adjusts
the balance between the rear and front pairs of
channels. The balancing technique described must
be carried out in MONAU RAL MODE. To balance
the
front channels, first set the FRONT-REAR
control all the way to the FRONT to silence the
rear speakers while you adjust the FRONT L-R
BALANCE control. To balance the rear channels,
move the FRONT·REAR control all the way to
REAR, and then adjust REAR L-R BALANCE.
Now you
are ready to adjust the FRONT-REAR
control
for the most pleasing overall balance.
SELECTOR SWITCH
The SELECTOR Switch selects the program
source
for listening or recording. The switch
can select any of six sources: AM, FM, PHONO,
CD-4/AUX, TAPE 1and TAPE
2.
BASS, MID AND TREBLE CONTROLS
These controls are used to adjust the tonal
balance
of program material to suit your indio
vidual listening preference. The bass, midrange
and treble responses are adjusted by dual-con-
centric, friction-coupled controls. With the BASS,
MID and TREBLE controls set at the center
position, frequency
response of the amplifier
becomes flat.
The larger (outer) knob adjusts the
response of
the front audio channels, while the smaller (inner)
knob adjusts the rear audio channels.
Turn the Tone Control knobs clockwise to boost
or counterclockwise
to attenuate their respective
frequency
ranges.
MONITOR SWITCH
When the MONITOR Switch is placed in the
TAPE 1
or TAPE 2position, the signals connect-
ed to the tape input jacks will be played back.
To play atape recorder that
is connected to the
TAPE MONITOR 1jacks, select TAPE 1
on the
SELECTOR Switch.
To monitor the tape on a
three-head recorder during recording,
place the
MONITOR Switch in the TAPE 1position.
To
playa tape recorder that is connected to the
TAPE MONITOR 2jacks, select TAPE 2
on the
SELECTOR Switch.
To monitor the tape on a
three-head recorder during recording, place the
8

MONITOR Switch in the TAPE 2position.
During recording, the MODE Switch should
be in
DISCRETE,
VARI-MATRIX or sa DECODER
positions. This applies the source signal, un-
changed, directly to the tape outputs.
To record adiscrete 4-channel source on a 2-
channel recorder, put the MODE Switch in the
2
CH position. Leave the MONITOR Switch in
the SOURCE position while recording. This will
feed the sum of the left-front and left-rear inputs
to the left·front TAPE MONITOR OUT jack, and
the
sum of the right-front and right-rear inputs
to the right-front TAPE MONITOR OUT jack.
To record any type
of source on amonaural
recorder,
put the MODE Switch in the MONO
position.
Leave the MONITOR Switch in the
SOURCE position while recording.
MAIN AND REMOTE SPKR SWITCHES
These switches select the loudspeaker terminals·
to wh ich audio power is fed. The MA I Nand
REMOTE groups of loudspeakers may be operat-
ed separately or simultaneously. With both
speaker switches in the "out" position, all loud-
speakers are disconnected. The signal at the
FRONT
and REAR PHOI\lES jacks is not
affected by the MAIN and REMOTE SPKR
Switches.
NOTE: When using both MAIN and REMOTE
speakers simultaneously, the combined
impedance
of all the speakers should not
be less than 4Ohms.
POWER SWITCH
This pushswitch turns the Power on or off. When
the POWER Switch is "in", the dial lamp illumi-
nates. Be sure to turn the POWER pushswitch
off before plugging or unplugging the power cord.
FRONT AI\lD REAR PHONES JACKS
These jacks accept astandard 3-conductor phone
plug employed with standard stereo or 4-channel
headphones. When using 2-channel headphones,
insert the plug into the FRONT PHONES jack.
When using 4-channel headphones, insert the
front plug into the FRONT PHONES jack and
the rear plug into the REAR PHONES jack.
Either high- or low-impedance headphones may
be used.
a
LOUDNESS SWITCH
When listening at low levels, set this switch "in".
The LOUDNESS Switch boosts bass and treble
tones
to compensate for the human ear's lack of
response to those frequencies at low volume
levels.
LOW FILTER SWITCH
With the pushswitch
set "in", the LOW FILTER
suppresses low frequency noise, such as turntable
rumble or
"boomy, exaggerated" bass. The use
of this filter will also reduce desired low fre-
quency sounds,
as well as unwanted noise. In the
"out" position, the LOW FILTER is switched
out
of the circuits.
HI
FI LTER SWITCH
With this pushswitch
set ";n", the High Fre-
quency Filter suppresses high frequency noise,
such as "scratch" from worn phonograph records
and tape "hiss". The
filter will also slightly
reduce high frequencies in the program material.
When the program does not have high frequency
noise, the HI
FILTER pushswitch should be
"out" .
METERS
The Model 4300
is eqUipped with two meters,
aSIGNAL·STRENGTH Meter
and an FM
TUNING Meter. The SIGNAL-STRENGTH Meter
indicates the signal-strength
of any AM or FM
broadcast. The FM TUNING Meter operates on
FM only and indicates correct station tuning. The
SIGNAL·STRENGTH Meter acts
as aDolby
Calibration Meter when the
DOLBY Switch is in
any position other than
"OFF".
TUNING
AM: For optimum AM reception, tune
to the
Figure 10. Stereophone Plug

desired station. Then, rock the TUNING knob
slightly back
and forth until the maximum
reading
is obtained on the SIGNAL-STRENGTH
Meter. The
FM TUNING Meter is not used for AM.
FM:
Set the SELECTOR Switch to "FM" and
tune
to the desired station. Then, slowly rock
the
TUNING knob back and forth until the FM
TUNING Meter points to the center scale po is-
tion.
FM MUTING SWITCH
When tuning to FM broadcasts with the FM MUT-
INGSwitch in its
"in" position, the muting circuit
will eliminate inter-station
noise. To prevent
muting
of very weak stations along with the
noise, the muting function may be turned off by
releasing the FM MUTING pushswitch to the
"out" position.
VOLUME
This control regulates volume
of all four channels
simultaneously.
DOLBY SWITCH
This switch
sets the Dolby noise-reduction circuit
for record or playback and also switches the
Meter Mode· from SIGNAL-STRENGTH
to
DOLBY CAL LEVEL, or vice-versa. With the
DOLBY Switch placed in
"OFF" position, the
Meter will
be used as aSIGNAL-STRENGTH
Meter; in all other positions,
as aDOLBY
LEVEL Meter.
DOLBY FM: This position
is used for listening
to Dolbyized FM broadcasts. The Dolby FM
level has been pre-adjusted at the factory.
PLAY:This·'lJosition is used to play back a
Dolbyized source (except FM).
OFF: With this position, the Dolby circuit
is
by-passed and the input signals are directly
applied
to both TAPE MONITOR OUT jacks
and amplifiers.
RECORD I: For making aDolbyized recording
from
an in-coming "flat" (non-Dolbyized) signal.
When the MONITOR Switch is set to the
SOURCE position, the
"flat" signal will be heard.
When making aDolby recording and utilizing a
three-head tape recorder, full advantage
of the
4300's 4-process Dolby System
can be ap-
preciated. When the 4300's MONITOR Switch is
in the TAPE 1or TAPE 2position, the signal
heard will be "flat", Le., it will be the sound
produced after the record
and playback Dolby
process has been completed.
RECORD
IT: For making a "flat" (non·Dolbyiz-
ed) recording from an in-coming Dolbyized signal.
Regardless of the position of the MONITOR
Switch, a
"flat" signal will be heard.
For further details on the use of the DOLBY
Switch, refer
to the "Dolby Mode Chart" on
page 16.
RECORD
LEVEL (L) (R)
These knobs control the record level of the signals
to be recorded through the Dolby unit. Adjust
the knobs
so that the Level Meter pointers of
the tape recorder do not exceed the OVU level.
PLAY CAL. (L) (R)
These knobs adjust the playback outputs from a
tape deck
to the proper Dolby level.
400Hz TONE SWITCH
This
is used for calibration of the record input
level of the tape deck. When the switch is
depressed, the built-in oscillator operates and a
sine wave signal output of 580mV will be applied
to the four TAPE MONITOR OUT jacks.
10

REAR PANEL FEATURES
FM ANTENNA TERMINALS
PHONO JACKS
CD-4/AUX JACKS
These jacks are for connection of any 4-channel
high
level equipment source. Manufacturers may
use different terminology for the four channels
and ~re should be exercised to avoid confusin~
the sIgnal channel terminations. The following
are examples of 4-channel nomenclature equiva-
lents:
These two jacks are intended for use with
magnetic cartridges requiring astandard
47000
Ohm resistive load. If ahum is heard ~hen
playing arecord, try reversing the polarity of
the turntable power plug. If this is ineffective,
connect a separate ground wire from the turn-
table
or record changer to the CHASSIS
GROUND binding post
of the 4300.
Connect the
FM antenna to these terminals. FOI
best FM reception, Marantz recommends a Log
Periodic antenna mounted on agood qualit)
rotor system. For rural areas, it is recommende(
that alocal dealer
be consulted about antenn;
installation
and lightning arrestor protection. J.
master antenna system is not recommended fo
use with your Model 4300, such systems ar
usually designed expressly for television receptiol
and frequently suppress FM signals before distr:
bution. In addition, master antenna
system
often severely limit quality FM reception. Wher
outdoor antennas are prohibited or inconvenien°
use asimple form of 300 Ohm TV "rabbit ear
antenna or the simple ribbon-type folded dipol
antenna supplied
with the 4300. Both are prat
tical and will give satisfactory results in primar
signal areas.
Your Model 4300 will accept either a75 Ohm (
300 Ohm antenna. (See Figure 11.) The 3C
Ohm antenna cable should be connected 1
the two terminals marked FM on the ANTENN
terminal.
When using 75 Ohm coaxial antenr
cable, connect its shield to the "G" tE
minai, and its inner or center conductor to eit
er of the FM terminals.
TRACK 1
TRACK 2
TRACK 3
TRACK 4
LF-LF-CHANNEL- 1
LR-LB-CHANNEL- 2
RF-RF-CHANNEL- 3
RR-RB-CHANNEL- 4
LEFT FRONT
LEFT REAR
RIGHT FRONT
RIGHT REAR
TAPE MONITOR IN AND TAPE
MONITOR OUT JACKS
These jacks are for the connection of a2-channel
or 4-channel tape recorder.
(Refer
to "SOURCE DEVICES", page 4.)
AM
ANTENNA TERMINAL
An external AM antenna can be connected
this terminal. The 4300
is equipped with a ferri1
ro~ antenna for AM reception and it will gi
satisfactory results in primary signal are;
Figure 11. FM/AM Antenna Connections
Figure 12. AM Ferrite-rod Antel

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
l
i
I
However, an outdoor antenna will provide better
reception.
Two single wires are required to make
an AM outdoor antenna. First, connect one end
of asingle wire to the AM ANTENNA terminal
on the rear panel, and the other end at avery high
position outdoors. Next, connect the othersingle
wire between the
"G" terminal and an earth
ground (such as awater pipe).
(Refer
to Figure 11.)
FM QUADRADlAL OUTPUT JACK
In anticipation
of discrete 4-channel stereo broad-
casts, your Model 4300 is equipped with an FM
QUADRADIAL OUTPUT jack. The signal avail-
able at this jack
is the unequalized output of the
FM discriminator. Its frequency response cha-
racteristics and signal level are ideal to drive any
4-channel adaptor. This jack
can also be used as
asimple white-noise generator for frequency
response check of loudspeakers or amplifiers.
For this application,
release FM MUTING Switch
of the Model 4300 in FM mode and tune off
from any FM signal.
FM DE-EMPHASIS SWITCH
Selects 75,uS or 25,uS FM DE-EMPHASIS for
accurate reception of Dolbyized FM signals.
DOLBY FM PRESET LEVEL CONTROLS
These factory-adjusted controls govern FM out-
put
level to the DOLBY circuit. These controls
are for the use of aqualified technician only.
MUTING
LEVEL CONTROL
Adjusts the threshold
of the inter-station muting
circuit. Turning this control counter-clockwise
will lower the threshold
to permit reception of
weak sigriars.
POWER MODE SWITCH
Switches from 100W x 2 operation
to 40W x 4.
In the 2-channel mode, only the front speaker
terminals
are used.
BE CERTAIN THAT THE UNIT'S POWER
SWITCH IS OFF BEFORE OPERATING THE
POWER MODE SWITCH.
NOTE:
When operating the unit in the 100W x 2
mode, all speaker terminals
are "above ground".
Consequently, the
use of any switching or testing
system which employs acommon ground will
activate the limiting circuits
and should therefore
be avoided.
PRE OUT, MAIN IN JACKS
For normal operation,
these jacks are inter-con-
nected
with the supplied jumpers. When con-
necting
an external unit (equalizer, reverberation
unit, etc.), remove the jumpers and connect the
PRE OUT jacks to the external unit's inputs. In
turn, connect the external unit's outputs
to the
MAIN IN jacks.
It is possible to create ahigher powered 4-channel
system by adding
an external amplifier.
If the external amplifier has less than 100 watts
x
2, it should be used to drive the rear speakers.
If the external amplifier has more than 100 watts
x
2, it should be used to drive the front speakers.
In each case, the rear panel POWER MODE Switch
should
be set to the 100W x 2 position.
CONNECTING
AN EXTERNAL AMPLIFIER
FOR REAR CHANNELS
To
use an extenral amplifier for the rear channels,
connect the REAR
PRE OUT jacks to the inputs
of the external amplifier. In turn, connect the
rear speakers to the output terminals on the ex-
ternal amplifier. The 4300 will then supply the
power
for the front speakers and the external
amplifier will supply the power
for the rear
speakers.
CONNECTING AN EXTERNAL AMPLIFIER
FOR FRONT CHANNELS
To use an external amplifier for the front channels,
connectthe REAR
PRE OUTjacks to the FRONT
MAIN IN jacks. Connect the rear speakers to the
FRONT
speaker terminals on the 4300. Then,
connect the FRONT
PRE OUT jacks to the inputs
of the external amplifier. In turn, connect the
front speakers to the output terminals on the
external amplifier. The 4300 will then supply the
power
for the rear speakers and the external am-
plifier will supply the power for the front speakers.
CHASSIS GROUND BINDING POST
Permits connection of the ground wire from a
turntable or other component
to reduce hum.
MAIN AND REMOTE SPEAKERS
Sixteen quick-connect terminals
are provided -
eight
for main speakers and eight for remote
speakers. (Refer to "CONNECTING THE 4300"
and "REMOTE SPEAKERS".)
12

Terminals work as shown in Figure 13.
1) Press terminal in
2) Insert speaker wire
3) Release terminal
CONNECTION TO AC OUTLET
With the
front panel POWER pushswitch "OUT"
plug the line cord into an electrical outlet supply-
ing the proper voltage.
CAUTION: DO NOT PLUG YOUR MODEL
4300 INTO A
DC OUTLET, AS
SERIOUS DAMAGE
WILL OCCUR.
AC CONVENIENCE OUTLETS
Two
AC outlets, one switched and one unswitch-
ed, are provided on the rear panel to supply
power
to associated components of the system
(tape recorder, record player, etc.). The maxi-
mum power available from the SWITCHED
and
UNSWITCHED AC OUTLETS is 100 Watts and
200 Watts, respectively.
REMOTE CONTROL
The REMOTE CONTROL connector and switch
are. intended for use only with the optional
Model RCA Remote Control.
The REMOTE
CONTROL Switch
assigns control of loudness,
balance and volume to the optional RC-4 Remote
Control. WHEN THE
RC-4 IS NOT USED,
THE REMOTE CONTROL SWITCH MUST BE
IN THE LOCAL POSITION.
EXTERNAL DECORDER CONNECTION
Apocket
on the bottom of the chassis will ac-
commodate Marantz 4-channel decoders, such as
the .~odel SOA-1. For use, follow the instruc-
tions'supplied
with the optional decoder.
TAPE RECORDING
Instructions
for connecting arecorder and playing
back atape
are given in "SOURCE DEVICES",
page 4.
To record, se.lect the desired program source,
using the SELECTOR Switch. Put the recorder
connected
to the TAPE MONITOR OUT jacks
"1 or 2" in the" Record" mode.
For additional information, refer
to MODE
SWITCH on page 7, and MONITOR SWITCH
on page 8.
POWER CONNECTIONS
The Model 4300
is designed to operate at 120
Volts
AC, 50/60Hz.
AC PROTECTOR FUSE
This feature automatically disconnects AC power
in the event of apower source or circuit failure.
If the POWER pushswitchis activated and the
front panel fails to illuminate and no sound is
heard through the speakers, unscrew the fuse
holder on the rear panel and visually inspect the
fuse to see if the internal conducting filament has
been broken. If so, replace the fuse with one hav-
ing the same specifications.
Figure 13. Quick-Connect Speaker Tennin;

BASIC DOLBY PROCESS
The Dolby system increases the level of low-level,
mid-
and high-frequency signals during recording
and reduces the level of these signals by an
identical amount during playback. As aresult,
the playback
signal is identical to the original
soUrce signal, but the level of background noise
generated by the tape recorder is greatly reduced.
ADolbyized
FM broadcast has already been
subjected to the first phase of the noise reduction
process before it is transmitted. When these
signals pass through the Dolby playback circuitry,
the mid-
and high-frequency noise is greatly
reduced.
DOLBY CALIBRATION
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.
The Model 4300 is capable of processing Dolby
signals from sources other than atape recorder
(AUX, PHONO, FM, ETC.).
NOTE:
It is possible to use the Dolby system for
recording al')d ,playing back tapes through your
system without using astandard alignment tape.
Procedures for making your own Dolby Align-
ment
Tape are as follows:
1. Thread ablank tape onto your recorder
(or insert acassette).
2. Set the 400Hz TONE Switch to the "ON"
(in) position.
3. Set your recorder's monitor switch to the
source position.
4. Set your recorder's record levels to 0VU.
5. Commence recording. Record about 45 se-
conds of the tone. This tape you have just
made is used to calibrate the Marantz Dolby
circuit with the recorder.
6. Switch off the 400Hz TONE.
However, aDolby recording
made on your re-
corder using the calibrated tape you have just
made may not necessarily be compatible with the
Dolby circuits in adifferent recorder
or systems.
Therefore, for universal compatibility, Marantz
offers astandard alignment tape which
is avail-
able from your local Marantz dealer.
NOTE: The Dolby system can be used with most
types
of tape recorders. However, it cannot be
used with recorders utilizing one set of level
control wh ich govern both record and playback
levels, or with recorders utilizing an Automatic
Level Control (A.L.C.) system.
PROCEDURE
FOR PLAYBACK CALIBRATION
1. Turn on the Model 4300 and your recorder.
2. Set the DOLBY function switch on the
Model 4300
to the PLAY position.
3. If your recorder has aSOURCEITAPE
(MON ITOR) Switch,
set it to "TAPE".
4. Load the Dolby standard alignment tape or
the calibration tape you
have made.
5. Play the Tape.
6. If your recorder does not have output
level controls, proceed to step 9.
7. If your recorder has output level controls
and the meters on the recorder read play-
back level, adjust the controls until the
meters
read "OVU". Then proceed to step 9.
8. If step 7 does not apply to your recorder,
set the output level controls to about 2/3
of fu II output.
9. Adjust the PLAY CAL controls (left and
right) on the 4300 to the DOLBY LEVEL
reference
on the SIGNAL·STRENGTH Me-
ter. To adjust the left PLAY CAL control,
place the METER Switch to the "OUT"
position. To adjust the right PLAY CAL
control, place the METER Switch to the
"I N" position.
10. You have now properly calibrated the Dolby
Playback
Level. From this point on, do not
change your recorder's output level controls
or the Model 4300'5
PLAY CAL controls.
14

Since the calibration is extremely stable and
should
not have to be repeated (except to period-
ically check
it), we suggest that you mark the
settings of your recorder's output level controls
with afelt-tipped
pen. Doing so will enable
you to easily reset the controls if they are
inadvertantly moved.
PROCEDURE FOR RECORD
CALIBRATION
Before proceeding with the record calibration,
be certain that the playback adjustments have
been performed. DO NOT CHANGE THEPOSI·
TIONS OF THE RECORDER'S
PLAYBACK
LEVEL CONTROLS (if any) OR THE 4300's
PLAY CAL CONTROLS.
When calibrating arecorder that is connected to
the TAPE MONITOR 1IN and OUT Jacks, be
sure the SELECTOR Switch is not in the TAPE
1position.
When calibrating arecorder that is
connected to the TAPE MONITOR 2 IN and
OUT Jacks,
be sure the SELECTOR Switch is
not in the TAPE 2position.
For Recorders
with Three Heads
1. Thread ablank tape onto your recorder (or
insert acassette).
2. Put the 4300's DOLBY Switch in the
"PLA Y" position.
3. Put both the 43OO's and the recorder's moni-
tor Switches in the "Tape" position.
4. Put the 400Hz TONE Switch in the
"ON"
(in) position.
5. Commence recording.
6. Adjust the recorder's record level controls
so the tone will deflect the 43OO's SIGNAL·
STRENGTH Meter to the "DOLBY LEVEL"
mark.
7. Switch off the 400Hz TONESwitch.
8. Dynamic monitoring will be acheived when
the
43OO's MONITOR Switch is in the
TAPE 1
or TAPE 2.
For Recorders with Two Heads
1. Thread ablank tape onto your recorder (or
insert acassette).
2. Put the 4300's DOLBY Switch in the "OFF"
position.
3. Put the 400Hz TONE Switch in the "ON"
(in) position.
15
4. Commence recording.
5. Adjust the recorder's record level controls
to deflect the recorder's meters to OVU.
6. Record the tone for approximately 30 sec-
onds.
7. Stop the recorder and rewind it to the begin-
ning
of the tone recording.
Switch
off the 400 Hz TONE .
8. Put the
43OO's DOLBY Switch in the
"PLA Y" position.
9. Put the recorder in the play mode and play
back the tape.
1 O. Note the level reading on the 4300's SIG-
NAL-STRENGTH Meter. To check the left
channel level, put the METER Switch in the
"OUT" position. To check the right chan-
nel level, put the METER Switch in the
"1 N" position. The object is to adjust the
recorder's record level controls so the play-
back level achieved indicates
"DOLBY LEV-
EL" on the 43OO's SIGNAL-STRENGTH
Meter.
11.
If the Meter indicates "DOLBY LEVEL",
calibration is completed.
12. A) If the Meter indication is above the
"DOLBY LEVEL", repeat steps 2 - 11,
but decrease the record level in step 5
to sl ightly below OVU on the recorder's
VU Meters.
B) If the Meter indication is below the
"DOLBY LEVEL", repeat steps 2 - 11,
but increase the record level in step 5
to slightly above OVU on the recorder's
VU Meters.
For all Recorders
After the "DOLBY LEVEL" has been achieved
on the SIGNAL-STRENGTH Meter,
DO NOT
change the recorder's
input or output level con-
trols
or the 4300's PLAY CAL controls.
Utilizing the recorder's
VLI Meters, proper Dolby
recording
levels are adjustable by using the R E-
CORD LEVEL controls on the front panel of the
4300. This only applies when making aDolby
recording.
CHANGING THE RECORDER'S RECORD
OR
PLAYBACK LEVELS OR THE 4300's PLAY
CAL CONTROLS WILL AFFECT THE DOLBY
CALIBRATION.

Mark the calibration positions on the recorder's
record
and playback level controls to avoid the
necessity
of re-calibrating after making anon-
Dolby recording.
IMPORTANT:
It will be necessary to re-calibrate the Dolby
levels when a change in tape speed has been made
or when adifferent brand or type of tape is used.
When the Dolby process is not desired on a re-
cording, record in the normal manner -adjusting
the record
levels with the recorder's record level
controls. DO NOT change the 4300's PLAY
CAL controls.
USE OF THE DOLBY SYSTEM ON FM BROAD-
CASTS
Your Model 4300 is equipped to receive Dolby-
ized FM broadcasts.
Most
FM broadcasts do not currently use the
Dolby Noise-Reduction system. To
receive FM
broadcasts which are not using the DOLBY
Noise-Reduction System,
leave the DOLBY
Switch in the
"OFF" position. However, if alocal
station
is broadcasting aDolbyized FM signal,
full
advantage of the increase in signal-to-noise
ratio may be obtained by putting the DOLBY
Switch in the
"DOLBY FM" position. The rear
panel DOLBY FM PRESET LEVEL controls are
factory-adjusted. Do not change the position
of these controls.
FM DE-EMPHASIS SWITCH
This
rear panel switch operates only when the
front panel DOLBY Switch is in the "DOLBY
FM" position. It alters the frequency response
of the FM signal. Normally, this switch should
be left in the 75~S position. However, if the
station
is broadcasting the Dolbyized signal using
a 25~S pre-emphasis, put this switch in the
"25~S" position to obtain flat FM frequency
response. If in doubt, call the station.
EXPLANATION OF THE
DOLBY MODE
CHART
This chart indicates the correct
DOLBY Switch
positions
for various types of input material.
The input format
is indicated in the left column
and the appropriate DOLBY Switch position,
together with
FM DE-EMPHASIS Switch position,
is shown under the appropriate mode of opera-
tion.
~
De-Emphasis Dolby Switch Position
ode Switch Record Notes:
Input Position Listening Without Dolby With Dolby
F.M.
75~
"Off"
"Off" "Record I"
-
(Normal)
F.M. If there
is a doubt regard-
with Dolby
75~s
"Dolby FM" "Record II"
"Dolby FM"
ing the pre-emphasis used on
75~s
the
transmission,
the F.M.
Pre-emphasi~
station should be contacted,
: .;
.where possible,
to ensure cor-
F.M.
with Dolby "Dolby FM" rect position for de-emphasis
25~
25~
"Dolby FM" "Record II"
switch.
Pre-emphasis
Non Dolbyized
sources -
"Off"
(Phono, Tape,
"Off"
"Record I" Pre-recorded tape manufac-
Aux inputs,
"Record I" turers indicate
when the ma-
A.M.) terial has been recorded
in a
Dolbyized format. Home
re-
Dolbyized corded tapes should also
be
sources (de- clearly marked as
to format,
rived from
"Play"
"Record II"
"Play"
to ensure correct play back
"Tape" or
-"Record II" mode.
"Aux" inputs
etc.)
For initial calibration, utilizing
the Dolby standard alignment tape, see detailed instructions
on Pages
14 thru 16 of this manual.
Table 1. Dolby Mode Chart
16

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SWITCH
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Figure 14. Block Diagram
17

TECHNICAL DESCRIPTION
GENERAL
Figure 14 is ablock diagram of the model 4300
Stereo 2+Quadradial 4Receiver showing main
functional elements and
input and output signal
routing. PHONO INPUT jacks
are provided for
the front pair of channels.
FUNCTIONAL DESCRIPTION
FRONT END
FM antenna signals are applied through abalun
transformer
to the antenna coil which drives a
field-effect transistor RF amplifier. The
signals
from the RF amplifier are fed through the double-
tuned RF tank
circuit to the F ET Mixer stage,
which is also fed by the signal generated by a
local oscillator. CarefuIattention
to its thermal
and electrical characteristics has minimized drift,
thus obviating the necessity for AFC. The 10.7
MHz converted
signal is then fed to aphase-linear
ceramic IFfilter, followed
by the limiter. The
output of the FM discriminator is fed to abuffer
amplifier which then drives the demodulator.
IF STAGES
The IF section consists
of six transistors and
three
stages of dual element ceramic filters.
The characteristics
of these filters are ideal in that
the 200KH.z. passband is phase-linear, with sharp
cutoff slopes. This exceptional phase linearity
assures the elimination of amajor source of high-
frequency distortion
and a loss of stereo separa-
tion. The sharp cutoff slopes provide improved
selectivity, permitting reception
of closely spaced
channels.
LIMITER
The Model 4300 utilizes symmetrical diode limit-
er circuits consisting of high-performance Gold
Bond Hot Carrier type diodes
and IF limiter
amplifier
with avery small dynamic symmetrical
aperture, eliminating the
need for an AGC circuit
wh ich introduces low frequency distortion. Un-
desirable amplitude modulation (AM signals, AM
noise, AM distortion)
are removed from the IF
signal within the limiter.
FM STEREO DEMODULATOR
The stereo composite
signal obtained from the
buffer amplifier
is first led to the FET muting
circuit; then
to the phase locked loop stereo
demodulator
IC circuit and decoded into both
left
and right channel signals. Each left and right
channel
signal is then applied to the 16KHz low
pass filter (LPF) and de-emphasis networks to
remove the undesired switching carrier signal in
the audio
signals. Next, each audio signal is ap-
plied to the audio amplifier consisting of NPN·
PNP direct-coupled transistors and amplified to
the required signal level of about 775mV RMS.
Finally, each amplified signal is led to the
SELECTOR Switch.
The multiplex stereo demodulator
circuit con-
sists of a phase locked loop Ie and is equipped
with a separate automatic Stereo/Monaural switch-
ing circuit. The circuit checks the
input signal
intensity and actuates the stereo demodulator
and stereo indicator lamp automatically, when the
input signal is of sufficient strength to provide
high quality stereo reception.
When the input
signal intensity is insufficient for this purpose,
the stereo
signal is automatically changed to a
monaural signal
to insure reception with ahigh
quality signal-to-noise ratio.
MUTING CIRCUIT
In the
absence of an FM carrier, all FM receivers
produce inherent noise. The muting circuit elim-
inates this noise, providing noise -free tuning
from station
to station.
Amuting circuit, consisting
of atwo-transistor
noise amplifier
and athree-transistor (including
FET) switching circuit,
has been incorporated
in the Model 4300. The muting
circuit perfectly
mutes
out all the inter-station noise and also com-
pletely mutes
out the side slope spurious response
of the unit. The circuit has been designed to
minimize annoying "pop" noise for velvet smooth
tune-in and tune-out.
AM TUNER
The
AM TUNER portion of the 4300 is compos-
ed of one IC circuit (including RF amplifier,
local oscillator, mixer, IF amplifier, detector
and
a signal strength indication amplifier) and one
transistor amplifier
to amplify the detected audio
signals. Athree-section variable capacitor im-
proves spurious
response ratio.
The ceramic
filter utilized in the AM IF amplifier
comes with high selectivity and wide band-
width
for interference-free hi-fi reception.
18