McIntosh MA6450 User manual

McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 139 3-2699 Phone: [phone] FAX: [phone]
OWNERS
MANUAL
MA6450
MA6450 Integrated Amplifier

2
Table of Contents
Thank You .......................................................................... 2
Please Take a Moment ....................................................... 2
Customer Service ............................................................... 2
Table of Contents ............................................................... 2
Safety Instructions ............................................................. 3
Introduction ........................................................................ 4
Performance eatures ........................................................ 4
Installation ......................................................................... 5
Rear Panel Connections ..................................................... 6
How to Connect ................................................................. 7
How to Connect for Video Switching ................................ 8
ront Panel Controls, Displays, Push-Buttons,
and Switches ...................................................................... 9
How to Operate ................................................................ 10
HR-033 Push-Buttons ...................................................... 12
How to Operate by Remote Control ................................ 13
Specifications .................................................................. 14
Packing Instruction .......................................................... 15
NOTES:
1. Connecting Cables are available from the McIntosh Parts
Department:
Data and Power Control Cable Part No. 170-202
Six foot, shielded 2 cond ctor, with 1/8 inch stereo mini
phone pl gs on each end.
2. For additional connection information, refer to the owners
man al(s) for any component(s) connected to the MA6450
Amplifier.
3. There is a b ilt-in t rn on delay which will m te the speaker
o tp ts for approximately two seconds when the amplifier is
t rned on.
4. If the rear panel processor switch is set to the in position, and
a signal processor is not connected, no so nd will be heard
thro gh the system. When a signal processor is connected to
the MA6450 processor jacks, and the processor switch is set
to the in position, the processor m st be on and operating, or
in bypass mode, for a so nd to be heard thro gh the system.
5. It is very important that lo dspeaker cables of adeq ate size
be sed in yo r m sic system, to ens re that there will be no
power loss or heating. Cable size is specified in Ga ge
n mbers or AWG, (American Wire Ga ge). The smaller the
Ga ge n mber, the larger the wire size:
If yo r lo dspeaker cables are 25 feet (7.62m) or less,
se at least 18 Ga ge (AWG) wire size or larger.
If yo r lo dspeaker cables are 50 feet (38.1m) or less,
se at least 16 Ga ge (AWG) wire size or larger.
If yo r lo dspeaker cables are 100 feet (76.2m) or less,
se at least 14 Ga ge (AWG) wire size or larger.
Copyright 1997 ã by McIntosh Laboratory, Inc.
Thank You, Please Take A Moment,
Customer Ser ice and Table of Contents
Customer Ser ice
If at any time you have questions about your McIntosh
MA6450 Intergrated Amplifier, contact your McIntosh
dealer. Your dealer is familiar with your McIntosh equip-
ment as well as other brands that may be included in your
system and is best qualified to help you.
If it is determined that your MA6450 is in need of repair,
you can return it to your dealer or you can return it to
McIntosh Laboratory. Contact the McIntosh Repair Depart-
ment for assistance at,
McIntosh Laboratory, Inc.
2 Chambers Street
Binghamton, New York 13903
Phone: [phone]
AX: 607-724-0549
Serial Number:
Purchase Date:
Dealer Name:
Thank You
or your decision to own this McIntosh MA6450 Inte-
grated Amplifier ranks you at the very top among discrimi-
nating music listeners. You now have The Best. The
McIntosh dedication to Quality, is assurance that you
will receive many years of musical enjoyment from this
unit.
Please take a short time to read the information in this
manual. We want you to be as familiar as possible with all
the features and functions of your new McIntosh MA6450.
This will ensure that you receive all the performance ben-
efits this equipment can offer you, and that it will become a
highly valued part of your home entertainment system.
Please Take A Moment
The serial number, purchase date and McIntosh dealer name
are important to you for possible insurance claim or future
service. The serial number is located on the rear panel of the
equipment. The spaces below have been provided for you to
record that information:

3
IMPORTANT SAFETY
INSTRUCTIONS
PLEASE READ THEM BEFORE
OPERATING THIS EQUIPMENT.
Safety Instructions
WARNING SHOCK HAZARD -
DO NOT OPEN.
AVIS RISQUE DE CHOC -
NE PAS OUVRIR.
NO USER-SERVICEABLE
PARTS INSIDE. REFER
SERVICING TO
QUALIFIED PERSONNEL
General:
1. Read all the safety and operating instructions, contained
in this owners manual, before operating this equipment.
2. Retain this owners manual for future reference about
safety and operating instructions.
3. Adhere to all warnings and operating instructions.
4. ollow all operating and use instructions.
5. Warning: To reduce risk of fire or electrical shock,
do not expose this equipment to rain or moisture.
This unit is capable of producing high sound pressure
levels. Continued exposure to high sound pressure
levels can cause permanent hearing impairment or
loss. ser caution is advised and ear protection is
recommended when playing at high volumes.
6. Caution: to prevent electrical shock do not use this
(polarized) plug with an extension cord, receptacle or
other outlet unless the blades can be fully inserted to
prevent blade exposure.
Attention: pour pevenir les chocs elecriques pas
utiliser cette fiche polarisee avec un prolongateur, une
prise de courant ou un autre sortie de courant, sauf si
les lames peuvent etre inserees afond ans en laisser
aucune partie a decouvert.
7. or added protection for this product during a lightning
storm, or when it is left unattended and unused for long
periods of time, unplug it from the wall outlet and dis-
connect the antenna or cable system. This will prevent
damage to the product due to lightning or power line
surges.
8. Do not use attachments not recommended in this
owners manual as they may cause hazards.
Installation:
9. Locate the equipment for proper ventilation. or ex-
ample, the equipment should not be placed on a bed,
sofa, rug, or similar surface that may block ventilation
openings; or, placed in a built-in installation, such as a
bookcase or cabinet, that may impede the flow of air
through the ventilation openings.
10. Locate the equipment away from heat sources such as
radiators, heat registers, stoves, or other appliance (in-
cluding amplifiers) that produce heat.
11. Mount the equipment in a wall or cabinet only as de-
scribed in this owners manual
12. Do not use this equipment near water; for example,
near a bathtub, washbowl, kitchen sink, laundry tub, in
a wet basement or near a swimming pool, etc.
13. Do not place this product on an unstable cart, stand,
tripod, bracket, or table. The equipment may fall, caus-
ing serious injury to a person, and serious damage to
the product.
Connection:
14. Connect this equipment only to the type of AC power
source as marked on the unit.
15. Route AC power cords so that they are not likely to be
walked on or pinched by items placed upon or against
them, paying particular attention to cords at plugs, con-
venience receptacles, and the point where they exit from
the instrument.
16. Do not defeat the inherent design features of the polar-
ized plug. Non-polarized line cord adapters will defeat
the safety provided by the polarized AC plug. If the
plug should fail to fit, contact your electrician to re-
place your obsolete outlet. Do not defeat the safety pur-
pose of the grounding-type plug.
17. Do not overload wall outlets, extension cords or inte-
gral convenience receptacles as this can result in a risk
of fire or electric shock.
Care of Equipment:
18. Clean the instrument by dusting with a dry cloth. Un-
plug this equipment from the wall outlet and clean the
panel with a cloth moistened with a window cleaner. Do
not use liquid cleaners or aerosol cleaners.
19. Do not permit objects of any kind to be pushed and/or
fall into the equipment through enclosure openings.

4
Performance Features
·100 Watt per Channel Integrated Amplifier
The MA6450 combines 100 watt per channel power ampli-
fier with a sophisticated control center in one compact unit.
·Multiple Inputs
Seven high level inputs provide for all popular program
sources.
·Tone Control Bypass
At the flat settings the Bass and Treble control circuit ele-
ments are removed from the Listen signal path.
·Active Loudness Circuity
A continuously variable active Loudness control allows
any degree of loudness compensation. All Loudness circuit
elements are removed from the signal path in the flat set-
ting.
·Electronic Input Switching
Digital Logic integrated circuits drive Electromagnetic
switches on all inputs and operating functions for reliable,
noiseless, distortion free switching
·Illuminated Peak Responding Output Meters
Output meters respond to 95% of full scale reading with a
single cycle of a 2KHz tone burst to indicate output power
with high accuracy.
·Power Guard with Sentry Monitor
Patented McIntosh Power Guard circuit that prevents the
amplifier from being overdriven into clipping with its harsh
distorted sound that can also damage your valuable loud-
speakers. Sentry Monitor power output stage protection
circuits ensure the MA6450 will have a long and trouble
free operating life.
·Speaker Switching
ront panel Speakers push-buttons control two pairs of
speakers.
·Special Power Supply
ully regulated power supply with a shielded power trans-
former ensures stable noise free operation.
Safety Instructions cont,
Introduction and Performance Features
Never spill liquids into the equipment through enclo-
sure openings.
20. Unplug the power cord from the AC power outlet when
left unused for a long period of time.
Repair of Equipment:
21. Unplug this equipment from the wall outlet and refer
servicing to a qualified service personnel under the fol-
lowing conditions:
A. The AC power cord or the plug has been damaged.
B. Objects have fallen, or liquid has been spilled into
the equipment.
C. The equipment has been exposed to rain or water.
D. The equipment does not operate normally by follow-
ing the operating instructions contained within this
owners manual. Adjust only those controls that are
covered by the operating instructions, as an im-
proper adjustment of other controls may result in
damage and will often require extensive work by a
qualified technician to restore the product to its nor-
mal operation.
E. The equipment has been dropped or damaged in any
way.
. The equipment exhibits a distinct change in perfor-
mance - this indicates a need for service.
22. Do not attempt to service beyond that described in the
operating instructions. All other service should be re-
ferred to qualified service personnel.
23. When replacement parts are required, be sure the ser-
vice technician has used replacement parts specified by
McIntosh or have the same characteristics as the origi-
nal part. Unauthorized substitutions may result in fire,
electric shock, or other hazards.
24. Upon completion of any service or repairs to this prod-
uct, ask the service technician to perform safety checks
to determine that the product is in proper operating con-
dition.
Introduction
The remote controlled MA6450 is a sophisticated, yet easy
to operate Integrated Amplifier that will provide the supe-
rior fidelity music reproduction that is traditional from
McIntosh. It includes a wide range of convenient operating
functions to enhance your listening enjoyment. The classic
McIntosh MA6450 will perfectly complement a pair of
McIntosh Loudspeakers for a stereo system of incompa-
rable performance and style.

5
Installation
The MA6450 can be placed upright on a table or shelf,
standing on its four feet. It also can be custom installed in a
piece of furniture or cabinet of your choice. The required
panel cutout, ventilation cutout and unit dimensions are
shown.
Always provide adequate ventilation for your MA6450.
Cool operation ensures the longest possible operating life
for any electronic instrument. Do not install the MA6450
directly above a heat generating component such as a high
powered amplifier. If all the components are installed in a
single cabinet, a quiet running ventilation fan can be a defi-
nite asset in maintaining all the system components at the
coolest possible operating temperature.
A custom cabinet installation should provide the follow-
ing minimum spacing dimensions for cool operation. Allow
at least 2 inches (5.1cm) above the top and 1 inch (2.54
cm) on each side of the amplifier, so that airflow is not ob-
structed. 21 inches (53.3cm) depth behind the mounting
panel, which includes clearance for connectors. Allow 1-1/
8 inches (2.9cm) in front of the mounting panel for knob
clearance. Be sure to cut out a ventilation hole in the
mounting shelf according to the dimensions in the drawing.
ront View of the MA6450
custom installed
Side View of the MA6450
custom installed
Bottom View of the MA6450
custom installed
Installation
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6
MA6450 Rear Panel Connections
MA6450 Rear Panel Connections
Connect the
MA6450 power
cord to a live AC
outlet. Refer to
information on the
back panel to de-
termine the cor-
rect voltage.
use holder,
refer to
infromation
on the back
panel to deter-
mine the cor-
rect fuse size
and rating.
The EXT (external)
Sensor for a McIntosh
IR sensor
DATA PORTS send signals
to compatible source com-
ponents to allow you to
remotely control them
POWER CONTROL
Output sends a turn-on
signal to a McIntosh
Component
PROCESSOR ROM
and TO jacks along
with PROCESSOR
IN-OUT switch for an
external signal proces-
sor
High Level Inputs
accept signals from
the output of a
TUNER, CD 1&2,
and AUX
TAPE 1, and
TAPE 2 inputs
are for tape
recorders
VIDEO, inputs for
audio signals from a
LD, VCR, TV or the
optional MVS-3 A/V
Selector
RECORD TAPE 1
and 2 OUTPUTS
supply record signals
for tape recorders
SPEAKERS 1 and
SPEAKERS 2 allow
two pairs of speakers
to be connected
SUM Data port
allows connection
of a McIntosh Re-
mote Control
Translator
SWITCHED
outlet turns on
and off with the
MA6450 main
power switch
MAIN OUTPUTS send signals to power amplifier
inputs, POWER AMP IN jacks accept signals from
an external preamplifier or signal source, EXT-INT
PWR AMP INPUT switch disconnects the power
amplifier from the built-in preamplifier
UNSWITCHED
outlet stays on all
the time

7
McIntosh CD Player
How to Connect the MA6450
How to Connect the MA6450
To AC Outlet
Tape Recorder
Signal Processor
McIntosh Tuner
McIntosh PC-3
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Left Loudspeaker
McIntosh
Remote
Sensor
Second Room
1. Connect the MA6450 power cord to a live AC outlet.
2. Connect cables from a pair of speakers to the
SPEAKER 1 Outputs.
Note: After connecting the
lo dspeakers, install the
s pplied protective covers
(located in an accessory
package in the shipping
carton) over the lo dspeaker
terminals.
3. Connect a cable from the TAPE 1 OUTPUTS to the
Record Inputs of a tape recorder and the TAPE 1 IN-
PUTS to a tape recorder Outputs.
4. Connect cables from a McIntosh CD Player to the CD1
INPUTS. Connect a McIntosh tuner to the TUNER IN-
PUTS.
5. Connect a cable from the POWER CONTROL jack to
the Power Control In on a McIntosh component or
Power Controller.
6. Connect a cable(s) from the DATA PORTS to the com-
ponents that are to be controlled by the MA6450.
7. Connect a Coax cable from the EXT SENSOR to a
McIntosh wall sensor or WK-2 Keypad in a second
room.
NOTE: If a Signal Processor is Used, connect cables from the
Signal Processor O tp ts to the PROCESSOR FROM
jacks and the Signal Processor Inp ts to the
PROCESSOR TO jacks. Set the MA6450 PROCESSOR
switch to IN. The processor m st be on or in bypass
mode for a signal to be heard.

8
McIntosh MVS-3
A/V Selector
How to Connect the MA6450
for Video Switching
How to Connect the MA6450 for Video
Switching
Monitor
McIntosh LD Player
To AC Outlet
1. Connect the MVS-3 power cord to the Switched outlet.
2. Connect a Data cable from the MA6450 VIDEO DATA
PORT to the MVS-3 DATA IN jack.
3. Connect the MVS-3 CONTROL CENTER OUTPUTS
to the MA6450 VIDEO Inputs.
4. Connect the MVS-3 VIDEO MONITOR OUTPUT to a
TV or Monitor.
5. Connect a McIntosh LD Player audio outputs to the
MVS-3 LV AUDIO INPUTS, the video output to the
MVS-3 LV VIDEO INPUT and the DATA OUT to the
MVS-3 LV DATA PORT.
6. Connect other video source components to the appro-
priate audio and video inputs on the MVS-3.

9
MA6450 Front Panel Controls,
Display, Push-Buttons and Switches
MA6450 Front Panel Controls, Display, Push-
Buttons and Switches
POWER ON/O
push-button turns
the MA6450 ON, or
O (Standby)
LOUDNESS control
(smaller inner knob)
provides adjustable fre-
quency response con-
toured to compensate
for the behavior of the
human ear at softer lis-
tening levels.
The BALANCE control
(large outer knob) al-
lows you to adjust the
relative volume balance
between channels.
TREBLE control provide
12dB boost or cut with a
flat center position.
BASS control provide
12dB boost or cut with
a flat center position.
VOLUME control allows
you to adjust the listening
level at the output(s)
Input switch selects
which of the five input
sources will appear at
the outputs
MONO push-
button combines
the left and right
channel signals
for Mono opera-
tion at the Main
and speaker out-
puts
Muting LED
lights to indicate
muting is active
POWER GUARD LEDs light
when the amplifier channel
Power Guard Circuit activates
SPEAKERS 1 and 2
push-buttons select one
pair of speakers, or both
pairs simultaneously
Copy tapes from
either of two tape
recorders to the
other
Select tape
playback
from either
of two tape
recorders
METERS indicate power
output of the amplifier
IR (Infra Red) sensor ac-
cepts IR signals directly
from an HR033 Remote
Control

1
Power On
Press the POWER push-button to turn the MA6450 on
and off.
Note: The red LE above the push-button stays on
whenever the MA6450 power cord is connected to a
live outlet. You may also turn the MA6450 on and off
using the HR033 Remote Control.
NOTE: Yo may also t rn on the MA6450 sing the HR033
Remote Control.
Source Selection
Select the desired listening source with the Input Switch.
Tape Mon 1 and 2
Press a TAPE MON (Tape Monitor) push-button to play-
back a previously recorded tape or monitor a tape playback
during the recording process.
NOTE: The TAPE MON p sh-b ttons are electronically
interlocked so only one recorder playback can be
selected at a time. If a 3 head tape recorder is being
sed, yo can monitor the tape playback d ring the
recording process by pressing the appropriate TAPE
MON p sh-b tton.
Volume Control
Adjust the VOLUME control for the desired listening
level.
Balance Control
Adjust the BALANCE control as needed to
achieve approximately equal listening volume
levels in each loudspeaker. Turn the BAL-
ANCE to the Left to emphasize the left channel
by reducing the level of the right channel. Turn
the BALANCE to the right to emphasize the
right channel by reducing the level of the left
channel.
Bass and Treble Controls
Adjust the BASS and TREBLE controls to suit
your listening preferences. The bass or treble
intensity can be increased with clockwise rota-
tion and decreased with counterclockwise rota-
How to Operate the MA6450
How to Operate the MA6450
tion. All tone control circuit elements are removed from the
signal path when the controls are in the center or flat posi-
tion.
Loudness Control
After first setting the desired listening volume, rotate the
LOUDNESS control clockwise to increase the intensity of
the bass according to your listening preference. When the
LOUDNESS control is in the fully counter clockwise or
flat position, all loudness circuit elements are removed
from the signal path.
Mono
Press the MONO push-button to combine left and right ste-
reo signals to mono at MAIN OUTPUT and SPEAKERS 1
and 2.
Mute
Press MUTE on the Remote Control to mute audio in the
MAIN OUTPUT and SPEAKERS 1 and 2. Press again,
select another Input or press a Tape Mon push-button to
unmute.
NOTE: When the MA6450 is in M te, the Speakers p sh-
b ttons, Mono p sh-b tton and Tape Copy p sh-b ttons
are inoperative.
Figure 1

11
How to Read the Power Output Meters
The MA6450 Power Output Meter scales are based on us-
ing 4 ohm loudspeakers. The meters are peak responding
and indicate the power output of each channel with high
accuracy when the amplifier is reproducing music. The
power outputs for the meter scale indications between the
numerical markings (high lighted in gray) are shown be-
low.
Speakers 1 and 2
Press SPEAKERS 1 or 2 push-buttons to switch the two
pairs of speakers on or off. You can press either push-but-
ton individually, or both together.
Reset of Microprocessors
In the event that the controls of the MA6450 stop function-
ing, remove the MA6450 power cord from the AC outlet.
Wait approximately two minutes and then replace the
power cord in the outlet. This will reset the MA6450 mi-
croprocessors and the amplifier should be functioning nor-
mally.
NOTE: The above condition is s ally ca sed by either
interr ptions in AC power and/or major changes in
voltage.
How to Make a Tape Recording
Select the desired input source to be recorded with the In-
put selector switch. This signal will appear at both Tape
Outputs 1 and 2 and allow either or both machines to
record the selected signal. The selected signal source will
also be available at the main outputs and both pairs of
speaker outputs. To play back the recording, press a TAPE
MON push-button. Refer to igure 1.
NOTE: If a 3 head tape recorder is being sed, yo can monitor
the tape playback d ring the recording process by
pressing the appropriate TAPE MON p sh-b tton.
How To Make an Audio Tape Copy
Press the TAPE COPY 1-2 push-button to copy tapes from
Tape Recorder 1 in playback mode to tape recorder 2 in
record mode. Press TAPE COPY 2-1 to copy tapes from
Tape Recorder 2 in playback mode to Tape Recorder 1 in
record mode. During the tape copy process, you can listen
to tape playback by pressing a TAPE MON push-button.
Refer to igure 1.
NOTE: Yo can also listen to any other signal so rce while
copying a tape.
How to Operate the MA6450
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12
HR033 Push-Buttons
HR033 Push-Buttons
Select any of the five high
level audio sources
Selects any one of five
externaly switched Audio/
Video Program Sources
Turns power ON to a
component connected via
the Data Port.
Adjusts the volume
level up or down
Selects tuner sta-
tions presets and
certain McIntosh
CD Players. Select CD player, CD
changer or tape recorder
functions.
Press to turn off
the MA6450
Press to turn the
MA6450 ON or
O
Use to select tuner
presets or any num-
bered operation.
Select M tuner
operating func-
tions.
Select AM tuner
operating functions
Select two pairs
of speakers
Mutes the
audio
Tunes to the next
radio station.
Note: The HR033 Remote Control p sh-b ttons
that are shown in black only work with
other McIntosh Prod cts.
Selects Tape
Monitor 1 or 2

13
How to Operate the HR033
How to Operate HR033
Mute
Press MUTE to mute the audio signals at the MAIN OUT-
PUTS and SPEAKERS. The MUTE LED, to the right of
the volume control will turn onto indicate that Mute is ac-
tive. Press MUTE a second time to unmute audio
Mono
Press the MONO push-button to combine left and right ste-
reo signals to mono at the MAIN OUTPUT and SPEAK-
ERS
Audio
Press any of the five Audio push-buttons to select a pro-
gram source.
Video/Audio Selection
When the optional McIntosh MVS-3 Audio/Video Selector
is added, first press VIDEO, and then the desired push-but-
ton to select any of the five A/V sources connected to the
MVS-3.
CD/Tape
Use these push-buttons to operate a CD player, CD changer
or tape recorder, when the component is connected to the
MA6450 with a McIntosh RCT Translator.
Numbered Push-buttons
Press push-buttons 0 through 9 to access tuner station pre-
sets or CD tracks/discs.
Tuner Push-buttons
Use with a McIntosh tuner. Select AM or M broadcast
band. Press and release SEEK Up or Down to move from
station to station. Press and hold a SEEK push-button to
move continuously from station to station. Press REVIEW
to start the automatic brief audition of each of the presets
stored in the tuner memory. Press REVIEW a second time
to stop on a station preset and exit the Review process.
Volume
Press the Up or Down VOLUME push-button to raise or
lower the listening volume level.
NOTE: The Tape Record O tp ts are not affected.
Speaker Selection
Press SPKR 1 or SPKR 2 push-buttons to switch two pairs
of speakers on and off separately or together.
Acc On
Press ACC ON to turn power ON of a McIntosh LV or
DVD Disc Player.
NOTE: When other brands of components are connected with a
McIntosh Remote Control Translator (RCT), refer to
the RCT Owners Man al for f rther information on
alternate HR033 p sh-b tton f nctions.

14
Specifications
Specifications
Power Output Per Channel
100 watts into 4 ohm loads minimum sine wave continuous
average power output per channel both channels operating.
Output Load Impedance
4 ohms
Rated Power Band
20Hz to 20,000Hz
Dynamic Headroom
2.4dB
Frequency Response
+0, -0.5dB from 20Hz to 20,000Hz
Total Harmonic Distortion
0.005% maximum at any power level from 250 milliwatts
to rated power per channel from 20Hz to 20,000Hz, all
channels operating.
Intermodulation Distortion
0.005% maximum if instantaneous peak output per channel
does not exceed twice the rated output with all channels
operating for any combination of frequencies from 20Hz to
20,000Hz.
Signal To Noise Ratio
110dB below rated output, Power Amplifier
100dB below rated output, Preamplifier
Sensitivity
250mV for 2.5V rated output, Preamplifier inputs
2.5V for rated output, Power Amplifier
Preamplifier Maximum Voltage Output
8V from 20Hz to 20,000Hz
Preamplifier Maximum Input Signal
10V
Damping Factor
Greater than 40
Power Requirements
100 Volts, 50/60Hz at 3.6 amps
110 Volts, 50/60Hz at 3.6 amps
120 Volts, 50/60Hz at 3.6 amps
220 Volts, 50/60Hz at 1.8 amps
230 Volts, 50/60Hz at 1.8 amps
240 Volts, 50/60Hz at 1.8 amps
NOTE: Refer to the rear panel of the MA6450 for the correct
voltage
Dimensions
ront Panel: 17/1/2 inches (44.5cm) wide, 5-3/8 inches
(13.7cm) high. Depth behind front mounting panel is 18 1/8
inches (46cm) including clearance for connectors. Panel
clearance required in front of mounting panel is 1-1/8
inches (2.9cm).
Weight
41 pounds (18.6Kg) net, 60 pounds (27.2Kg) in shipping
carton

15
Packing Instructions
In the event it is necessary to repack the equipment for ship-
ment, the equipment must be packed exactly as shown be-
low. It is very important that the four plastic feet are at-
tached to the bottom of the equipment. This will ensure the
proper equipment location on the bottom pad. ailure to do
this will result in shipping damage.
Use the original shipping carton and interior parts only if
they are all in good serviceable condition. If a shipping car-
ton or any of the interior part(s) are needed, please call or
write Customer Service Department of McIntosh Labora-
tory. Please see the Part List for the correct part numbers.
Quantity Part Number Description
1 033838 Shipping carton only
2 033837 End Cap ( oam Pad)
1 033836 Inside carton only
1 033725 Top Pad
1 033698 Bottom pad
3 017218 Plastic foot (spacer)
1 033699 Wood skid
3 101169 #10 x 2-¼ Wood screw
3 104033 #10 x 1-¾ Wood screw
4 017218 Plastic foot
4 100159 #10-32 x ¾ Machine screw
4 104080 #10 x 7/16 lat washer
1 048432 Shipping carton complete with
all the above parts
Packing Instructions

McIntosh Part No. 040561
McIntosh Laboratory, Inc.
2 Chambers Street
Binghamton, NY 13903