McIntosh MC-275 Mk5 Owners manual

Stereo Power Amplifier

MC275

Owner’s Manual

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

The lightning flash with arrowhead,
within an equilateral triangle, is
intended to alert the user to the
presence of uninsulated “danger­ous voltage” within the product’s
enclosure that may be of sufficient
magnitude to constitute a risk of
electric shock to persons.

The exclamation point within an
equilateral triangle is intended to
alert the user to the presence of im­portant operating and maintenance
(servicing) instructions in the litera­ture accompanying the appliance.

WARNING - TO REDUCE RISK OF

FIRE OR ELECTRICAL SHOCK, DO

NOT EXPOSE THIS EQUIPMENT TO

RAIN OR MOISTURE.

IMPORTANT SAFETY

INSTRUCTIONS!

PLEASE READ THEM BEFORE
OPERATING THIS EQUIPMENT.

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Do not use this apparatus near water.

6. Clean only with a dry cloth.

7. Do not block any ventilation openings. Install in
accordance with the manufacturer’s instructions.

8. Do not install near any heat sources such as radia­tors, heat registers, stoves, or other apparatus
(including amplifiers) that produce heat.

9. Do not defeat the safety purpose of the polarized
or grounding-type plug. A polarized plug has two
blades with one wider than the other. A ground­ing type plug has two blades and a third ground­ing prong. The wide blade or the third prong are
provided for your safety. If the provided plug does
not fit into your outlet, consult an electrician for
replacement of the obsolete outlet.

10. Protect the power cord from being walked on or
pinched particularly at plugs, convenience re­ceptacles, and the point where they exit from the
apparatus.

NO USER-SERVICEABLE PARTS

INSIDE. REFER SERVICING TO

QUALIFIED PERSONNEL.

To prevent the risk of electric shock, do not remove cover or

back. No user-serviceable parts inside.

11. Only use attachments/accessories specified by the
manufacturer.

12. Use only with the cart, stand, tripod, bracket, or
table specified by the manufacturer,
or sold with the apparatus. When a
cart is used, use caution when mov­ing the cart/apparatus combination
to avoid injury from tip-over.

13. Unplug this apparatus during lightning storms or
when unused for long periods of time.

14. Refer all servicing to qualified service person­nel. Servicing is required when the apparatus has
been damaged in any way, such as power-supply
cord or plug is damaged, liquid has been spilled or
objects have fallen into the apparatus, the appara­tus has been exposed to rain or moisture, does not
operate normally, or has been dropped.

15. Do not expose this equipment to dripping or
splashing and ensure that no objects filled with liq­uids, such as vases, are placed on the equipment.

16. To completely disconnect this equipment from the
a.c. mains, disconnect the power supply cord plug
from the a.c. receptacle.

17. The mains plug of the power supply cord shall
remain readily operable.

18. Do not expose batteries to excessive heat such as
sunshine, fire or the like.

2

Thank You

Your decision to own this McIntosh MC275 Stereo Power
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: ___________________________________

Table of Contents

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

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

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

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

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

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

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

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

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

Installation of Tubes and Tube Cover ..........................................6

Location and Ventilation .............................................................7

Connections:

Left Side Panel Connections .......................................................8

Right Side Panel Connection and Fuse Holder ...........................9

How to Connect for Stereo ........................................................10

How to Connect for Mono Parallel ............................................11

Left Side Panel Controls and Switches ......................................12

Operation:

How to Operate ..........................................................................13

Additional Information:

Specifications ............................................................................14

Packing Instructions ..................................................................15

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]

General Information

1. Caution: To prevent electrical shock make sure that
the AC POWER CORD IS NOT CON­NECTED TO THE MC275 when inserting
or removing Vacuum Tubes, as there are
hazardous voltages present at the pins of
the Tube Sockets.

2. When Vacuum Tubes are installed or removed make

sure to reattach the Tube Cover to the MC275 Chassis.

3. If the MC275 has been On, please allow the Hot Vacu-

um Tubes to cool first before removing them.

4. For additional connection information, refer to the

owner’s manual(s) for any component(s) connected to
the MC275.

5. The Main AC Power going to the MC275 and any other

McIntosh Component(s) should not be applied until all
the system components are connected together. Failure
to do so could result in malfunctioning of some or all of
the system’s normal operations.

Copyright 2006 © by McIntosh Laboratory, Inc.

3

Connector Information, Introduction and Performance Features

PIN 1

PIN 2

PIN 3

Connector and Cable Information

XLR Connectors

Below is the Pin configuration for the XLR Balanced Input
Connectors on the MC275. Refer to the diagram for con­nection:
PIN 1: Shield/Ground
PIN 2: + Output
PIN 3: - Output

Introduction

Now you can take advantage of traditional McIntosh stan­dards of excellence in the MC275 Stereo Power Amplifier.
Two 75 watt output channels will drive any high quality
Loudspeaker System to its ultimate performance. The
MC275 reproduction is sonically transparent and abso­lutely accurate. The McIntosh Sound is “The Sound of the
Music Itself.”

Performance Features

• Power Output

The MC275 consists of two separate power amplifier chan
nels, each capable of 75 watts into 4, 8 or 16 ohm Loud­speakers in stereo. It may also be operated in mono at 150
watts into 2, 4, or 8 ohm Loudspeakers.

• Bifilar Wound Transformers and Output Circuit

The Power Output Sections utilize the famous McIntosh
Patented Unity Coupled Circuit with a Bifilar Wound
Output Transformer for low distortion, extended frequency
response and cool operating output tubes.

• Balanced and Unbalanced Inputs

Balanced connections guard against induced noise and al
low long cable runs without compromising sound quality.

• Gold Plated Connectors and Tube Socket Contacts

Gold Plated Input Jacks and Output Binding Posts provide
trouble free connections. Ceramic tube sockets with gold
plated contacts provide protection from atmospheric con
tamination. Output Tube Sockets include Air-Pipe cooling
at their bases.

-

-

-

• Super Mirror Chassis Finish

The famous McIntosh Stainless Steel Chassis with Super
Mirror Finish ensures the pristine beauty of the MC275
will be retained for many years.

4

Dimensions

16-1/2"

41.91cm

Front View of the MC275

Top View of the MC275

Left Side View
of the MC275

Right Side View
of the MC275

7-7/8"

20.00cm

8-1/4"

20.96cm

13-5/8"

34.61cm

12"

30.48cm

1-3/4"

4.45cm

1-3/4"

4.45cm

1-1/4"

3.18cm

4-3/8"

11.11cm

5-9/16"

14.13cm

The following dimensions can assist in determining the
best location for your MC275. There is additional infor­mation on page 7 pertaining to installing the MC275 into
cabinets.

Dimensions

5