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To balance a stereo system using the

TWIN AMP input position use a monophonic

signal from the program source. A mono-

phonic signal supplies the same voltage to
both channels. Turn the volume control on

the source equipment to the 12 o'clock posi-

tion (half rotation). Turn up the GAIN con-
trol on the LEFT input until the loudness in

the room is not quite as loud as you like to

listen. Then turn the GAIN control on the

RIGHT input until it is equally as loud as the

left channel. The system is now balanced for

loudness and provides the most convenient
amount of loudness change when using the

volume control on the source equipment.

MONO

With the switch in the right position

marked MONO the inputs of the MC240 are

internally connected in parallel to the jack

marked MONO INPUT. This jack is located
below the right control knob marked GAIN.

The input sensitivity in this position is 0.5

volt. The GAIN control should be adjusted to

match the input voltage sensitivity of the
MC240 to the output voltage of the program

source.

For maximum flexibility set the GAIN con-

trol as follows: turn the volume control on
the program source equipment (i.e. tape

recorder, tuner, preamplifier, etc.) to the

12 o'clock (half rotation) position. Turn the

GAIN control on the MC240 until the loud-

ness of the sound from the speaker is just a
little louder than you normally like to listen.

The volume control on the program source

equipment now has the most convenient

amount of loudness change in either direc-

tion from the 12 o'clock position.

IMPORTANT

The excellent performance that is inher-

ent in all Mclntosh amplifiers does not

depend on the critical adjustment of bias or

balance controls in the output circuit. The
patented Mclntosh circuit delivers its adver-

tised specifications without any need for

these controls and is not dependent on care-

fully balanced tubes for its performance.

With Mclntosh you can install the amplifier
and forget it.

The MC240 you have purchased will give

you years of pleasant and satisfactory per-
formance. If you have any questions con-
cerning the operation or maintenance of this
amplifier please contact:

Mclntosh Laboratory Incorporated guar-

antees this equipment to perform as adver-

tised. We also guarantee the mechanical and

electrical workmanship and components of
this equipment to be free of defects for a

period of 90 days from date of purchase.

This guarantee does not extend to compo-

nents damaged by improper use nor does it

extend to transportation to and from the

factory.

3-YEAR FACTORY SERVICE CONTRACT

An application for a FREE 3-YEAR FAC-

TORY SERVICE CONTRACT is included in the

pocket in the back cover of this manual. The

FREE 3-YEAR FACTORY SERVICE CONTRACT

will be issued by Mclntosh Laboratory upon

receipt of the completely filled out applica-

tion form. The term of this contract is defined

in the 3-year factory service contract. If the

application is not mailed to Mclntosh Labo-

ratory only the services offered under the
standard 90-day guarantee will apply on this

equipment. TAKE ADVANTAGE OF 3 YEARS

OF FREE FACTORY SERVICE BY FILLING

IN THE APPLICATION NOW.

In Canada: Manufactured under license by:

McCurdy Radio Industries, Ltd.
22 Front Street West

Toronto, Canada

Design subject to change without notice.

GUARANTEE

Customer Service

Mclntosh Laboratory, Inc.

2 Chambers Street

Binghamton, New York

Our telephone number is 723-5491.

The direct dial area code is 607.

8

Summary of Contents for MC 240

Page 1: ...DESCRIPTION 1 PANEL FACILITIES 4 INSTALLATION 5 CONNECTIONS 5 Input Stereo 5 Input Twin Amp 5 Input Mono 6 Output Stereo or Twin Amp 6 Output Mono 6 Line Output Stereo or Twin Amp 6 Line Output Mono 7...

Page 2: ......

Page 3: ...ty of the MC240 permits it to be used as a monophonic amplifier that delivers 80 watts or as two separate 40 watt amplifiers with each chan nel amplifying completely separate pro grams or as two ampli...

Page 4: ...ack loop which reduces their distortion reduces their internal generator resistance and reduces their balance requirements The Mclntosh circuit in reality perfects push pull high efficiency output cir...

Page 5: ...0 7 volts Mono Isolated from ground 25 volts Center tap internally grounded 140 volts One side internally grounded 70 7 volts Internal Impedance Less than 10 of rated load impedance Input Input impeda...

Page 6: ...t has a GAIN control that permits connecting signal sources up to 30 volts without overloading the amplifier s input The input impedance is 250 000 ohms OUTPUT The two barrier terminal strips marked O...

Page 7: ...nd must be attached to the amplifier bottom at each end Turn the MC240 over with the transform ers down and place it on a piece of cloth or cardboard to prevent scratches The ampli fier is shipped wit...

Page 8: ...the output volt ages are not the same phase and amplitude If the speaker impedance is 2 ohms 4 ohms 8 ohms 16 ohms 32 ohms Connect one speaker lead to the screw marked LEFT COM and the other to LEFT 4...

Page 9: ...the following adjustments have been completed the MC 240will operatewithoutanyfurtherattention ADJUSTMENTS LINE VOLTAGE The LINE VOLTAGE switch should be set to the position that more closely matches...

Page 10: ...oes not depend on the critical adjustment of bias or balance controls in the output circuit The patented Mclntosh circuit delivers its adver tised specifications without any need for these controls an...

Page 11: ......

Page 12: ...2 CHAMBERS STREET BINGHAMTON N Y Phone Area Code 607 723 5491 LABORATORY INC Made in U S A PRINTED IN U S A 1M 038 002...

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