McIntosh MC303 User Manual

Page 3

Thank You

Your decision to own this McIntosh MC303 Power Ampli-

fier ranks you at the very top among discriminating music

listeners. You now have “The Best.” The McIntosh dedica-

tion 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: 607-723-1545

Fax: 607-724-0549

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: 607-723-3515

Fax: 607-723-1917

Table of Contents

General Information

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

Thank You and Please Take a Moment .............................. 3

Technical Assistance and Customer Service ..................... 3

Table of Contents ............................................................... 3

General Information .......................................................3-4

Connector Information ...................................................... 4

Introduction ........................................................................ 4

Performance Features ........................................................ 4

Dimensions ........................................................................ 5

Installation ......................................................................... 6

Rear Panel Connections and Switch .................................. 7

How to Connect .............................................................. 8-9

Connection Diagrams (Separate Sheet) MC1A and MC1B

Front Panel Displays and Controls ....................................10

How to Operate .................................................................11

Technical Description ..................................................12-15

Photos ...........................................................................16-17

Specifications ....................................................................18

Packing Instruction ...........................................................19

Caution: The MC303 Amplifier weight is 150 pounds (70.3

kilograms). It requires two or more persons to safely

handle when moving the amplifier.

1. The following Connecting Cable is available from the McIn-

tosh Parts Department:

Power Control Cable Part No. 170-202

Six foot, 2 conductor shielded, with two 1/8 inch stereo

mini phone plugs.

2. For additional connection information, refer to the owner’s

manual(s) for any component(s) connected to the MC303.

3. The MC303 mutes the speaker output for approximately two

seconds when first turned on.

4. In the event the MC303 overheats, due to improper ventilation

and/or high ambient temperature, the protection circuits will

activate. The Front Panel Power Guard LEDs will continu-

ously indicate ON and the audio will be muted. When the

MC303 has returned to a safe operating temperature, normal

operation will resume.

5. For the best performance it is important to minimize an im-

pedance mismatch. An impedance mismatch can occur when a

Loudspeaker of a given impedance rating is connected to the

MC303 Output Terminals with a different impedance rating.

For example, a Loudspeaker with an impedance rating of 2

Ohms is connected to the MC303 8 Ohm Output Terminals.

The impedance of a Loudspeaker actually varies as the

Loudspeaker reproduces different frequencies. As a result, the

nominal impedance rating of the Loudspeaker (usually mea-

sured at a midrange frequency) might not always agree with

the impedance of the Loudspeaker at low frequencies where

the greatest amount of power is required.