McIntosh C-38 Owners manual

C38

SYSTEM

CONTROL

CENTER

IMPORTANT

SAFETY

INSTRUCTIONS

THESE

INSTRUCTIONS

ARE TO PROTECT

YOU AND THE

MclNTOSH

INSTRUMENT.

BE SURE TO

FAMILIARIZE

YOURSELF

WITH THEM

1. Read all instructions - Read the safety and operating instructions before operating the instrument.

2. Retain Instructions - Retain the safety and operating instructions for future reference.

3. Heed warnings - Adhere to warnings and operating instructions.

4. Follow Instructions - Follow all operating and use instructions.

WARN

STRUMENT TO RAIN OR MOISTURE.

5. Power Sources - Connect the power supply only to the type described in the operating instructions
or as marked on the unit.

6. Power-Cord Protection - Route power-supply 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,
convenience receptacles, and the point where they exit from the instrument.

7. Ventilation - Locate the instrument for proper ventilation. For example, the instrument 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.

8. Heat - Locate the instrument away from heat sources such as radiators, heat registers, stoves, or
other appliance (including amplifiers) that produce heat.

9. Wall or Cabinet Mounting - Mount the instrument in a wall or cabinet only as described in the owner's

manual.

10. Water and Moisture - Do not use the instrument near water - for example, near a bathtub, washbowl,
kitchen sink, laundry tub, in a wet basement, or near a swimming pool, etc.

11. Cleaning - Clean the instrument by dusting with a dry cloth. Clean the panel with a cloth moistened

with a window cleaner.

12. Object and Liquid Entry - Do not permit objects to fall and liquids to spill into the instrument through
enclosure openings.

13. Nonuse Periods - Unplug the power cord from the AC power outlet when left unused for a long period
of time.

14. Damage Requiring Service - Service must be performed by qualified service personnel when:
A. The power supply cord or the plug has been damaged; or

B. Objects have fallen, or liquid has been spilled into the instrument; or

C. The instrument has been exposed to rain; or

D. The instrument does not appear to operate normally or exhibits a marked change in performance;

or

E. The instrument has been dropped, or the enclosure damaged.

15. Servicing - Do not attempt to service beyond that described in the operating instructions. All other
service should be referred to qualified service personnel.

16. Grounding or Polarization - Do not defeat the inherent design features of the polarized plug. Non­polarized line cord adaptors will defeat the safety provided by the polarized AC plug.

17.

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 PREVENIR

FICHE POLARISEE AVEC UN PROLONGATEUR, UNE PRISE DE COURANT OU UNE AUTRE
SORTIE DE COURANT, SAUF SI LES LAMES PEUVENT ETRE INSEREES A FOND SANS EN
LAISSER AUCUNE PARTIE A DECOUVERT.

ING: TO

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.

REDUCE

RISK

OF

FIRE

LES

OR

ELECTRICAL SHOCK,

CHOCS ELECTRIQUES

DO NOT

PAS

EXPOSE

THIS

IN-

UTILISER CETTE

Copyright 1992 © by

Mcintosh Laboratory Inc.

CAUTION: TO

REMOVE COVER (OR BACK). NO USER-SERVICABLE PARTS INSIDE.
REFER SERVICING TO QUALIFIED PERSONNEL.

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.

PREVENT

THE

RISK

OF

ELECTRIC

SHOCK, DO NOT

WARNING: THIS UNIT IS CAPABLE OF PRODUCING HIGH SOUND

PRESSURE LEVELS. CONTINUED EXPOSURE TO HIGH SOUND

PRESSURE LEVELS CAN CAUSE PERMANENT HEARING IMPAIRMENT

OR LOSS. USER CAUTION IS ADVISED AND EAR PROTECTION IS

RECOMMENDED WHEN PLAYING AT HIGH VOLUMES.

2

Your decision to own this piece of Mcintosh Stereo Equipment 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 thousands of hours 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 piece of Mcintosh. This will ensure that you

receive all the performance benefits this instrument can offer you, and that it will become a highly valued

part of your home music system.

The serial number, purchase date, and Mcintosh Laboratory Service Contract number are

important to you for possible insurance claim or future service. Record this information here.

THANK
YOU

Serial Number

Service Contract Number

Upon application, Mcintosh Laboratory provides a Service Contract to the original purchaser.
Your Mcintosh Authorized Service Agency can expedite repairs when you provide the Ser­vice Contract with the instrument for repair.

SERVICE CONTRACT 4

INTRODUCTION . 5

HOW TO INSTALL THE C38 . . .6
FRONT PANEL CONTROLS, SWITCHES AND PUSHBUTTONS 6, 7, 8
HR38 HAND HELD REMOTE CONTROLLER 8, 9
THE REAR PANEL AND HOW TO MAKE CONNECTIONS 9, 10, 11, 12, 13
SPECIFICATIONS 14
PERFORMANCE CHARTS . . 15

TECHNICAL DESCRIPTION 16, 17

INSTALLATION DIAGRAM : . 18

Purchase Date

TABLE OF
CONTENTS

3

MclNTOSH

THREE YEAR

SERVICE

CONTRACT

TAKE ADVANTAGE OF 3 YEARS OF CONTRACT SERVICE. . .

FILL IN THE APPLICATION NOW.

Your C38 System Control Center will give you many years of satisfactory performance. If you
have any questions, please contact,

Mcintosh Laboratory Inc.

2 Chambers Street

Binghamton, New York 13903-2699
Phone: [phone]

An application for A THREE YEAR SERVICE CONTRACT is included with this manual.
The terms of the contract are:

1. If the instrument covered by this contract becomes defective, Mcintosh will provide all parts,
materials, and labor needed to return the measured performance of the instrument to the
original performance limits free of any charge. The service contract does not cover any
shipping costs to and from the authorized service agency or the factory.

2. Any Mcintosh authorized service agency will repair all Mcintosh instruments at normal
service rates. To receive the free service under the terms of the service contract, the ser-

vice contract certificate must accompany the instrument when taken to the service agency.

3. Always have service done by a Mcintosh authorized service agency. If the instrument is

modified or damaged as a result of unauthorized repair the service contract will be cancell­ed. Damage by improper use or mishandling is not covered by the service contract.

4. The service contract is issued to you as the original purchaser. To protect you from

misrepresentation this contract cannot be transferred to a second owner.

5. Units in operation outside the United States and Canada are not covered by the Mcintosh
Factory Service Contract, irrespective of the place of purchase. Nor are units acquired

outside the USA and Canada, the purchasers of which should consult with their dealer
to ascertain what, if any, service contract or warranty may be available locally.

4

Mcintosh Laboratory has earned a world wide reputation for its technical contributions for
improved sound reproduction. Mcintosh products incorporate an advanced level of technical
innovations that have integrity proven by time. The Mcintosh "Classic" design is also recogniz­ed as the most outstanding in the industry.

Mcintosh products are designed to be maximum user friendly, so anyone can enjoy using
them. Another Mcintosh design policy is to provide products that are easy to maintain. The
legendary reliability of Mcintosh products is a matter of record since 1949.

The C38, Remote Controlled, System Control Center is a perfect example of a simple, yet
elegant instrument which will allow you to enjoy outstanding music reproduction together
with a wide range of convenient operating functions. The C38 has a built-in capability of con­trolling two separate listening areas. The LISTEN signals are defined as Area A which is usually
the main area where all the sound equipment is located. The RECORD signals are available
at a pair of outputs marked B, and can be used for a remote area with its own dedicated
power amplifier and pair of speakers.

Data ports are provided for seven audio remote controlled accessories. This feature allows
you to control a compatible unit by transmitting with its hand held remote controller direct
to a C38 sensor. A data port is also provided to control the optional Mcintosh MVS-3 Video
Selector for switching video signals in addition to audio signals. Another data port connects
to the optional Mcintosh HC-1 Home Controller to allow control of accessories or appliances.

The convenience of C38 remote control operation is enhanced by its capability of directly

interfacing with the Mcintosh CR10 Remote Control System. The CR10 can add an additional

four remote areas of control.

There are eight pairs of high level inputs to accommodate all the traditional program sources
as well as the most recent new sources. A pair of low level inputs is also provided that will
accept signals from a moving magnet phono cartridge in a record player. Digital Logic in­tegrated circuits drive Electromagnetic Switches on all inputs and operating functions for the
most reliable and distortion free switching available.

Separate RECORD and LISTEN circuits allow recording from one source while listening
to another. A continuously variable Active Loudness Control allows loudness compensation
to be selected for any setting of the volume control. The Loudness Control circuit elements
are removed from the circuit path when the control is in the flat or fully counterclockwise
position.

Bass and Treble tone controls provide 12dB of boost or cut. At the center "Flat Response"
or detent position of the tone controls, all tone control circuit elements are removed from
the signal path.

Two Signal Processor loops are provided. One is for Listen signals and one is for Record
signals. Power supply voltage regulator circuits maintain stable operation even though the

AC power line may vary. Double shielding of the power transformer completely isolates it from
the audio circuits. This eliminates the need for a clumsy outboard power transformer used

by some less sophisticated designs.

Front panel pushbuttons control two switched outputs as well as two pairs of speakers

when an optional SCR3 switching relay is added.

The Mcintosh C38 "Classic Glass" front panel has all control, switch and pushbutton

nomenclature illuminated.

INTRODUCTION

5

HOW TO

INSTALL

THE C38

FRONT PANEL

CONTROLS,

SWITCHES

AND

PUSHSBUTTONS

The C38 can be placed upright on a table or shelf, standing on its own plastic feet. It can
also be installed in an optional Mcintosh L72 equipment cabinet. Follow the mounting instruc­tions enclosed with the L72 cabinet.

The C38 can also be custom installed in a piece of furniture or cabinet of your choice.
The required panel cutout and unit dimensions are shown on Page 18 of this manual.

Always provide adequate ventilation for your C38, even though it develops very little heat.

Cool operation insures the longest possible operating life for any electronic instrument. Do

not install your C38 directly above a heat generating component such as a high powered
amplifier. In a system stack, the power amplifier should always be at the top. If all the com-

ponents are installed in a single cabinet, a quiet running ventilation fan can be a definite asset

in maintaining all the system components at the coolest possible temperatures.

A custom cabinet installation should allow the following recommended minimum spacing

dimensions for cool operation. Allow at least 1 1/2 inches (3.8cm) above the unit so airflow

is not obstructed. Allow 17 inches (43.2cm) 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.

The back cover of this manual folds out to show photographs of the front and rear

panels of the C38. Fold it out to assist you in identifying and locating the front panel

controls, switches, pushbuttons, and the rear panel connectors. The letters and
numbers on the photographs refer to the information that follows.

A. BASS AND TREBLE

Provide 12dB boost and cut, with neutral flat response at the center detent position. The
Bass and Treble controls affect only the MAIN, SWITCHED 1 and 2 and BALANCED (Area
A) outputs.

B. RECORD

Selects the program signal that will feed the TAPE 1, TAPE 2, TAPE 3 and Area B OUT­PUT jacks.

C. INFRARED SENSOR

This IR sensor accepts commands from the HR38 hand held remote controller.

D. LISTEN

Selects the program signal that feeds the MAIN, SWITCHED 1 and 2, and BALANCED

(Area A) outputs.
E. VOLUME

Adjusts the volume level at the MAIN, SWITCHED 1 and 2, AND BALANCED (Area A)
outputs. The volume level can be controlled by manually adjusting the VOLUME knob, or press­ing the appropriate (Up) or (Down) button on the HR38 hand held Remote Controller.

The volume level is controlled in remote Area B by using the HR38 transmitting to a

wall mounted IR sensor or by a WK-1 keypad.

The TAPE OUTPUT and Area B volume levels are not affected by the C38 front panel
VOLUME control settings.

TURN ON CHARACTERISTICS

Area A: The Program signal and volume settings last used will be in effect.
Area B: The Tuner signals will automatically be selected with volume at 50dB below maximum.

6