Mcintosh MA352 User Manual

McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 13903-2699 Phone: [phone] www.mcintoshlabs.com

MA352

Integrated Amplifier

Owner’s Manual

Important Safety Information is supplied in a separate document “Important Additional Operation Information Guide”

Thank You

Your decision to own this McIntosh MA352 Integrated
Amplifier ranks you at the very top among discrimi­nating 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.

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 spaces below have been
provided for you to record that information:

Serial Number: _______________________________

Purchase Date: _______________________________

Dealer Name: ________________________________

Technical Assistance

If at any time you have questions about your McIntosh
product, contact your McIntosh Dealer who is familiar
with your McIntosh equipment and any other brands
that may be part of your system. If you or your Dealer
wish additional help concerning a suspected problem,
you can receive technical assistance for all McIntosh
products at:

McIntosh Laboratory, Inc.
2 Chambers Street
Binghamton, New York 13903
Phone: [phone]
Fax: [phone]

Customer Service

If it is determined that your McIntosh product is in
need of repair, you can return it to your Dealer. You
can also return it to the McIntosh Laboratory Service
Department. For assistance on factory repair return
procedure, contact the McIntosh Service Department
at:

McIntosh Laboratory, Inc.
2 Chambers Street
Binghamton, New York 13903
Phone: [phone]
Fax: [phone]

Table of Contents

Safety Instructions .............................................................. 2

(Separate Sheet) ............................Important Additional

Operation Information Guide

Thank You and Please Take a Moment ...............................2

Technical Assistance and Customer Service .......................2

Table of Contents ................................................................. 2

Important Information ......................................................... 3

Unpacking the MA352......................................................4-5

General Information ............................................................ 6

Connector and Cable Information ....................................... 6

Introduction ......................................................................... 7

Performance Features .......................................................... 7

Dimensions .......................................................................... 8

Installation ........................................................................... 9

Connections:

Rear Panel Connections ..................................................... 10

Connecting Components and Loudspeakers ................ 11-12

MA352 Switch Power On ................................................. 13

Remote Control and Front Panel:

Remote Control Push-buttons ........................................... 14

How to use the Remote Control ......................................... 15

Front Panel Displays, Controls and Jack ........................... 16

Setup Mode:

How to Operate the Setup Mode ....................................... 17

Setup Functions:

Default Settings ......................................................... 17

Fi r mware Versi o n ...................................................... 17

Source Input On/Off and Renaming .................... 17-18

Output 2, Passthru ..................................................... 19

Data Por t .................................................................... 19

Comm Port Baud Rate ............................................... 20

Remote Control Codes ...............................................20

IR Sensor ....................................................................20

Power Mode ...............................................................21

Factory Reset .............................................................21

Operation:

How to Operate the MA352 .........................................22-25

Trim Functions:

Balance .......................................................................22

Equalizer Mode ..........................................................23

Mono/Stereo Mode ....................................................23

Output 1 and 2 ...................................................... 23-24

Tri m Level ..................................................................24

Meter Illumination .....................................................24

Tube Lig ht s ........................................................... 24-25

Information Display Illumination .............................25

Information Display Activity ....................................25

Reset of the Microprocesors .............................................. 25

Specifications and Equalizer Controls .............................. 26

Packing Instructions .......................................................... 27

Copyright 2019 © by McIntosh Laboratory, Inc.

2

IMPORTANT!

INSTRUCTIONS FOR REMOVAL

OF FOAM INSERT OVER THE

VACUUM TUBES PRIOR TO

CONNECTING THE A.C. POWER

SUPPLY CORD, START ON THE

NEXT PAGE.

3

Caution: To prevent damage to the MA352

Tubes during shipping, there is a
special foam insert surrounding the
Tubes of the Integrated Amplifier.

The Foam Insert must be

removed from the MA352
before connecting the AC
Power Supply Cord to the
integrated amplifier.

2. Remove the Warning Sheet and save it with the
Shipping Carton for possible future use. Refer to
figures A and B.

3. Carefully lift upright the Foam Insert Vacuum
Tube Cover and place it near to the MA352 Inte­grated Amplifier. Refer to figure C.

BAL 1 15%

125

30

2K 10K

500

Failure to do so has the po-

tential of a Fire Hazard,
resulting in damage to the
MA352 and the surrounding
environment.

Follow these instructions for

removal of the packing foam
before connecting the AC
Power Supply Cord to the
MA352.

The MA352 has no user serviceable parts,
including the tubes. If repairs are needed they
must be performed by an authorized McIntosh
Service Agency. Follow the steps below to pre­pare the MA352 for operation:

1. Orient the MA352 so the Front and Top of the
Integrated Amplifier is facing you. Refer to
figure A.

WARNING

TO AVOID A FIRE HAZARD, THE FOAM INSERT
OVER THE VACUUM TUBES MUST BE REMOVED

V1 - 12AX7A

PRIOR TO CONNECTING THE A.C. MAINS POWER
SUPPLY CORD AND OPERATING THIS PRODUCT.

REFER TO PAGE 3 IN THE MA352 OWNER’S

V3 - 12AT7

INPUT

HEADPHONES

PUSH - TRIM

MANUAL FOR INSTRUCTIONS.

30 125 500 2k 10k

Figure A

Remove the Warning Sheet

V1 - 12AX7A

V3 - 12AT7

INPUT

PUSH - TRIM

HEADPHONES

30 125 500 2k 10k

Figure B

Vacuum Tube Shield Covers

V2 - 12AX7A

V2 - 12AX7A

Figure C

Remove the Foam
Insert Vacuum

V4 - 12AT7

VOLUME

STANDBY

PUSH - POWER

4. Remove from the Foam, the four Vacuum Tube

Tube Cover

Shield Covers and place them along the side of the
MA352 Integrated Amplifier. Save the Foam In­sert Vacuum Tube Cover with the Shipping Carton
for possible future use. Refer to figure D.

Remove the four Vacuum Tube Shield Covers

V4 - 12AT7

VOLUME

STANDBY

PUSH - POWER

Figure D

4

WA R NI NG:

The supplied Vacuum Tube Shield
Covers must be installed over each
of the four Small Vacuum Tubes
before the MA352 Integrated Am­plifier is connected to AC Power
and activated for use!!

5. The MA352 Integrated Amplifier has four Small
Vacuum Tubes that are inserted into special
Vacuum Tube Sockets on the Stainless Steel Chas­sis. Refer to figure E.
Each of the Tube Sockets have four pin openings
to accept the Vacuum Tube Shield Covers. Refer
to figure F.
Carefully install the Vacuum Tube Shield Covers
into each of the Vacuum Tube Sockets orienting
the Shield so the “Mc” on top of the Shield is fac­ing forward. Refer to figures G and H.

V1 - 12AX7A

Unpacking the MA352

V2 - 12AX7A

Failure to do so has the potential to
cause physical harm to human be­ings and animals.

This could also result in damage to
the Vacuum Tubes and the MA352
Internal Circuitry.

It also prevents the potential of a
Fire Hazard, resulting in damage
to the MA352 and the surrounding
environment.

V3 - 12AT7

INPUT

HEADPHONES

PUSH - TRIM

Figure E

Pin Openings

V1 - 12AX7A

30 125 500 2k 10k

V2 - 12AX7A

STANDBY

Special Vacuum Tube Sockets

Vacuum Tube
Shield Covers

Figure F

PUSH - POWER

V4 - 12AT7

VOLUME

V3 - 12AT7

PUSH - TRIM

V4 - 12AT7

INPUT

HEADPHONES

30 125 500 2k 10k

VOLUME

STANDBY

PUSH - POWER

Figure G

BAL 1 15%

125

30

2K 10K

500

Figure H

5

General Information

1. For additional connection information, refer to the
owner’s manual(s) for any component(s) connected
to the MA352.

2. Apply AC Power to the MA352 and other McIntosh
Component(s) only after all the system components
are connected together. Failure to do so may cause
a malfunction of system operations as the Micro­processor’s Circuitry inside the components is
active when AC Power is applied.

3. The MA352 includes an Auto Off Power Save
Feature and the default setting is enabled. For
additional information including how to disable it,
refer to page 21.

4. When Power Amplifier Protection Circuitry of the
MA352 has activated, the Vacuum Tubes LEDs are
illuminated continuously with the color orange and
the sound will be muted.

5. When the Power Transformer has overheated due
to improper ventilation and/or high ambient operat­ing temperature, AC Power is removed from the
MA352. Normal operation will resume when the
operating temperature is in a safe range again.

6. The MA352 Remote Control is capable of operating
other components. For additional information go to
www.mcintoshlabs.com.

7. The IR Input, with a 3.5mm mini phone jack, is
configured for non-McIntosh IR sensors such as
a Xantech Model HL85BK Kit. Use a Connection
Block such as a Xantech Model ZC21 when two
or more IR sensors need to be connected to the
MA352. The signal from a connected External IR
Sensor will have priority over the signal from the
Front Panel IR Sensor.

General Information, Connector and Cable Information

8. When discarding the unit, comply with local rules
or regulations. Batteries should never be
thrown away or incinerated but disposed
of in accordance with the local regula­tions concerning battery disposal.

9. For additional information on the MA352 and
other McIntosh Products please visit the McIntosh
Website at www.mcintoshlabs.com.

Connector and Cable Information

XLR Connectors

Below is the Pin configuration for the XLR Balanced
Input Connectors on the MA352. Refer to the diagram
for connection:
PIN 1: Shield/Ground
PIN 2: + Output

PIN 1

PIN 3: - Output

Power Control Connector

The Power Control Output Jack sends Power On/
Off Signals (+12 volt/0 volt) when
another McIntosh Component is
connected. A 3.5mm stereo mini
phone plug is used for connection to
the Power Control Output.

Data Port Connector

The Data Out Ports send Remote Control Signals to
Source Components. A 3.5mm stereo
mini phone plug is used for connec­tion.

PIN 3

Power
Control

Data
Signal

PIN 2

N/C

Ground

N/C

Data
Ground

RS232 Data Port Cable

The RS232 Data Cable is a

3.5mm stereo mini phone plug
for use with a compatible control
system.

Data In
(DB9-pin2)

Data Out
(DB9-pin3)

Output Terminal Connector

When cables with spade lugs are used
for Loudspeaker Connection, the spade
lugs need an opening of at least 3/10 inch
(7. 6 mm).

Ground
(DB9-pin5)

3/10 of an inch
(7.6millimeters)

6

Introduction

Now you can take advantage of traditional McIntosh
standards of excellence in the MA352 Integrated Am­plifier. The Power Amplifier Solid State section of the
MA352, with a power output of 200 watts per channel
at 8 ohms, will drive a pair of quality Loudspeakers to
a high level of performance.

The flexible Tube Preamplifier section provides

connections for various analog input sources.

The MA352 reproduction is sonically transparent
and absolutely accurate. The McIntosh Sound is “The
Sound of the Music Itself.”

Performance Features

• Power Output

The MA352 consists of 200 watts (8 ohm) or 320
watts (4 ohm) per channel Stereo Power Amplifier
with less than 0.03% distortion. The McIntosh MA352
is designed for connection of a single 8 ohm or 4 ohm
Loudspeaker per channel. The Power Amplifier uses
Ther malTrak1 Output Transistors for lower distortion
and cool operation.

• Power Guard

The patented McIntosh Power Guard circuit prevents
amplifier clipping and protects your valuable Loud­speakers.

• Sentry Monitor and Thermal Protection

McIntosh Sentry Monitor power output stage protec­tion circuits ensure the MA352 will have a long and
trouble free operating life. Built-in Thermal Protection
Circuits guard against overheating.

1

ThermalTrak™ and ON Semiconductor are trademarks of Semi-

conductor Components Industries, LLC

• Electronic Input and Output Switching

The Preamplifier uses Logic Controlled Electromag­netic Switches on all low level inputs and outputs. The
operating functions are for reliable, noiseless, distor­tion free switching.

• Moving Magnet Phono Inputs

The MA352 Moving Magnet Input Circuitry uses
the latest design to provide the lowest possible noise,
distortion and flat frequency response.

• Equalizer Controls

The five Front Panel Equalizer Controls provide 12dB
of boost or cut at their center frequencies. The MA352
remembers the Equalizer Circuitry Setting (On or
Off) for each input.

• Multifunction Display

The Front Panel Display indicates source selection,
volume levels and setup functions.

• Power Control Output

A Power Control connection for convenient Turn-On
of a McIntosh Component.

• Remote Control

The Data Port together with the supplied Remote Con­trol provide control of McIntosh Source Components
connected to the MA352.

• Special Power Supply

The large Power Transformer, multiple filter capaci­tors with 60 Joules of Energy Storage and regulated
Power Supply ensure stable noise free operation even
though the power line varies.

Introduction and Performance Features

• McIntosh Custom Binding Posts

McIntosh Patented gold plated output terminals deliver
high current output. They accept large diameter wire
and spade lugs. Banana plugs may also be used only in
the United States and Canada.

• Super Mirror Finish Chassis with Glass Panel

The famous McIntosh Stainless Steel Chassis with
Super Mirror Finish ensures the pristine beauty of the
MA352 will be retained for many years. The famous
McIntosh Illuminated Glass Panel uses long life Light
Emitting Diodes (LEDs).

7

Dimensions

"

The following dimensions can assist in determining
the best location for your MA352. There is additional
information on the next page pertaining to installing
the MA352 into cabinets.

Front View of the MA352

Dimensions

Right Side View of the MA352

17-1/2"

44.5cm

BAL 1 15%

125

30

2K 10K

500

Rear View of the MA352

12-7/16"

31.6cm

13-1/4

33.7CM

8-7/8"

22.5cm

5-3/4"

14.6cm

3"

7.62cm

9-7/8"

25.1m

1-1/2"

3.8cm

1-1/2"

3.8cm

9-1/4"

23.5

6"

15.2CM

13-3/8"

CM

33.9

Top View of the MA352

CM

17-7/16

44.3CM

16-3/4"

CM

42.5

V3 - 12AT7

PUSH - TRIM

V1 - 12AX7A

INPUT

HEADPHONES

30 125 500 2k 10k

V2 - 12AX7A

V4 - 12AT7

VOLUME

STANDBY

PUSH - POWER

8

Installation

The MA352 Integrated Amplifier is designed to be
placed upright on a table or shelf, standing on its feet.
The required ventilation requirements are shown.
Always provide adequate ventilation for your MA352.
Cool operation ensures the longest possible operating
life for any electronic instrument. Do not install the
MA352 directly above a heat generating device, such
as a Power Amplifier. Allow at least 6 inches (15.3cm)
above the top, 5/8 inch (1.6cm) below the bottom and
2 inches (5.1cm) on each side of the Amplifier, so that
airf low is not obstructed. Allow 22 inches (55.9cm) of
depth for airf low and cable connections.

MA352 Front View

2"

5.1cm

6"

15.3cm

BAL 1 15%

125

30

Installation

2"

5.1cm

2K 10K

500

MA352 Side View

6"

15.3cm

22"

55.9cm

9