THE MclNTOSH MC 2100 SOLID STATE STEREO POWER …sportsbil.com/mcintosh/Amps/MC2100/MC2100_own.pdf · Your MC 2100 stereo amplifier will give you many years of pleasant and satisfactory

THE MclNTOSH MC 2100 SOLID STATE STEREO POWER AMPLIFIER

Price $1.25

Your MC 2100 stereo amplifier willgive you many years of pleasantand satisfactory performance. Ifyou have any questions concerningoperation or maintenance pleasecontact the dealer from whomyou purchased this instrument or:—

CUSTOMER SERVICE

Mclntosh Laboratory Inc.2 Chambers StreetBinghamton, New York 13903Phone: 607-723-3512

Take Advantage of 3 years

of FREE Factory Service . . .

Fill in the Application NOW.

CONTENTS GUARANTEE

INSTALLATION

HOW TO CONNECT

CONTROL PANEL INFORMATION

LISTENING TO YOUR STEREO SYSTEM

PERFORMANCE LIMITS

PERFORMANCE CHARTS

TECHNICAL DESCRIPTION

BLOCK DIAGRAM

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GUARANTEEMclntosh Laboratory Incorporated guarantees this

Instrument to be capable of performance as adver-tised. We also guarantee the mechanical and elec-trical workmanship and components to be free ofdefects for a period of 90 days from date of pur-chase. If such defects occur, Mclntosh Laboratory

or one of its authorized agencies will repair thedefect at no cost to the purchaser. This guaranteedoes not extend to components damaged by im-proper use nor does it extend to transportation toand from the factory or service agency.

THREE YEAR FACTORY SERVICE CONTRACT

An application for a FREE THREE YEAR FACTORYSERVICE CONTRACT is included with this manual.The terms of the contract are:

For Three Years from date of purchase —1. Mclntosh will provide all parts, materials and

labor needed to return the measured performanceof the instrument to the original performancelimits free of any charge. The SERVICE CON-TRACT does not cover any shipping costs to andfrom the authorized service agency or the factory.

2. Any Mclntosh authorized service agency will re-pair all Mclntosh instruments at normal servicerates. To receive the free service under the termsof the SERVICE CONTRACT, the SERVICE CON-TRACT CERTIFICATE must accompany the instru-ment when taken to the service agency.

3. Always have service done by a Mclntosh author-ized service agency. If the instrument is modifiedor damaged, as a result of unauthorized repair theSERVICE CONTRACT will be cancelled. Damageby improper use or mishandling is not covered bythe SERVICE CONTRACT.

4. The SERVICE CONTRACT is issued to you as theoriginal purchaser. To protect you from misrepre-sentation this contract cannot be transferred to asecond owner.

5. The SERVICE CONTRACT is given to purchaserswho live in the 50 United States or Canada only.

6. For your protection Mclntosh selects its dealerscarefully. Only one dealer in ten qualifies for aMclntosh franchise. To receive the SERVICECONTRACT your purchase must be made from aMclntosh franchised dealer.

7. Your completely filled In application for a SERV-ICE CONTRACT must be postmarked within 30days of the date of purchase of the instrument.

8. To receive the SERVICE CONTRACT all informa-tion on the application must be filled in. TheSERVICE CONTRACT will be issued when thecompletely filled in application Is received atMclntosh Laboratory Incorporated In Binghamton,New York. If the application is not received atMclntosh Laboratory, only the service offeredunder the 90-day guarantee will apply.

Copyright © 1972 By Mclntosh Laboratory Inc.

1

INSTALLATIONAdequate ventilation extends the trouble-free

life of electronic instruments. It is generally foundthat each 10° centigrade (18° F) rise in tempera-ture reduces the life of electrical insulation by onehalf. Adequate ventilation is an inexpensive andeffective means of preventing insulation break-down that results from unnecessarily high operat-ing temperatures. The direct benefit of adequateventilation is longer, trouble-free life.

The suggested minimum space for mounting theMC2100 is 20 inches deep x 9½ inches high x 12inches wide. Always allow for air flow by eitherventilation holes or space next to the bottom ofthe amplifier and a means for the warm air toescape at the top.

It is recommended that the MC2100 be mountedin a normal or horizontal position. However withadequate ventilation, the amplifier can be mountedin any position except upside down. If the ampli-fier is to be installed on a vertical surface it isrecommended that the autoformers be on thedown side. This position permits greater air flowaround the transistors and component parts there-by extending the trouble-free life of the amplifier.

HOW TO CONNECTINPUT-STEREO

The shielded cable from the left output of theMclntosh preamplifier is plugged into the left jack. Theshielded cable from the right output of the Mclntoshpreamplifier is plugged into the right jack. The INPUTswitch must be in the STEREO position and the OUT-PUT properly connected to the stereo loudspeakersor distortion and loss of power may result.

INPUT-MONOThe shielded cable from the program source is

plugged into the right jack. The INPUT switch mustbe in the MONO position and the OUTPUT properlyconnected for mono loudspeaker operation or distor-tion and loss of power may result.

OUTPUT-STEREO OR TWIN AMPLIFIERSFor stereo or twin channel operation it is not nec-

essary to use the same impedance loudspeaker oneach output. Simply connect each channel for theimpedance desired.

SPEAKERSSpeakers are connected at the barrier strips marked

OUTPUT on the sloped panel of the amplifier. Uselamp cord, bell wire, or wire with similar type of insula-tion to connect the speakers to the amplifier. For thenormally short distances of under 50 feet between theamplifier and speaker, #18 wire or larger can beused. For distances over 50 feet between the amplifierand speaker use larger wire.

The loudspeaker impedance is usually identified onthe loudspeaker itself. Connect one of the leads fromthe left loudspeaker to the screw marked COM on theLEFT OUTPUT barrier strip. Connect the other leadfrom the left loudspeaker to the screw marked with thenumber corresponding to the speaker impedance onthe LEFT OUTPUT barrier strip. Connect one of theleads from the right loudspeaker to the screw markedCOM on the RIGHT OUTPUT barrier strip. Connect theother lead from the right loudspeaker to the screwmarked with the number corresponding to the speakerimpedance on the RIGHT OUTPUT barrier strip.

The only adverse effect on the operation of aMclntosh amplifier when it is improperly matched is areduction in the amount of distortion-free power avail-able to the loudspeaker. Close impedance matching isdesirable for maximum distortion-free power.

SPEAKER CONNECTIONSUse this table to determine proper speaker connec-

tion:Connect the

If the speaker impedance speaker leadsis between: between COM and:

3.2 to 6.5 ohms 4 ohms6.5 to 13 ohms 8 ohms13 to 26 ohms 16 ohms

STEREO OUTPUT-CONNECTING TO BARRIER STRIPSUse this table for stereo connections using the

barrier strips:Connect one right

Connect one left speaker lead tospeaker to screw the screw marked

If the speaker LEFT-COM and RIGHT-COM andimpedance is: other to: the other to:4 ohms LEFT-4 RIGHT-48 ohms LEFT-8 RIGHT-8

16 ohms LEFT-16 RIGHT-16

For 25 volt line operation connect one of the left leadsto the screw marked COM on the LEFT OUTPUTbarrier strip. The other left lead is connected to thescrew marked 8 on the LEFT OUTPUT barrier strip.Connect the right leads in the same manner on theRIGHT OUTPUT barrier strip.

When connected as above the MC 2100 operates as a105 watt per channel stereo amplifier.

2

MONOPHONIC OUTPUT—CONNECTING TOBARRIER STRIPS

When the NIC 2100 is to operate as a monophonicamplifier, the two channels are combined to produce asingle 210 watt output. This chart lists the proper con-nections and interconnections for monophonic opera-tion.

If thespeakerimpedanceis:

2 ohms

4 ohms

Connect one speakerlead to the screwmarked LEFT-COMand the other to:

LEFT-4

LEFT-8

8 ohms LEFT-16For constant voltage

25 volts LEFT-8

Connect awire between:

LEFT-4 andRIGHT-4LEFT-8 andRIGHT-8LEFT-16 andRIGHT-16

LEFT-8 andRIGHT-8

When connected as above the MC 2100 operates as a210 watt per channel monophonic amplifier.

STEREO OUTPUT—CONNECTING TOTHE OCTAL SOCKETThe octal socket marked OUTPUT can be used for allof the output impedances and voltages. Connectionsare made in the following fashion:

If theimpedance is:

Solder the leftchannel leadsbetween:

4 ohms Pin 1 and 28 ohms Pin 1 and 3

16 ohms Pin 1 and 4For constant voltage25 volts Pin 1 and 3

Solder the rightChannel leadsbetween:

Pin 5 and 6Pin 5 and 7Pin 5 and 8

Pin 5 and 7

When connected as outlined the MC 2100 operates asa 105 watt per channel stereo amplifier.

MONOPHONIC OUTPUT—CONNECTINGTO THE OCTAL SOCKETIf theimpedance is:2 ohms4 ohms8 ohms

25 volts

CONNECT2 and 63 and 74 and 84 and 8

Solder theleads to:1 and 21 and 31 and 41 and 4

When connected as outlined the MC 2100 operates asa 210 watt monophonic amplifier.

AC POWER:The power requirement for the MC2100 is 117 to 130

volt, 50/60 Hz. The amplif ier wi l l be turned on and offif its power cord is plugged in one of the auxil iary ACpower outlets on the program source.

3

CONTROL PANEL INFORMATIONINPUT

The input of the MC 2100 has a two position switchto permit the amplifier to be used in any one of threeways:

(1) As a monophonic 210 watt amplifier.(2) As twin 105 watt amplifiers used with an elec-

tronic crossover network, or as two completelyseparate amplifiers.

(3) As a stereo amplifier used with a Mclntosh pre-amplifier or other high output stereo programsources.

In either position of the input switch the input sensi-tivity is 0.5 volts for full rated output. The input im-pedance is 200,000 ohms.

In the STEREO position each input is controlled bya GAIN control. The GAIN control allows signalsources of 0.5 volt up to 30 volts to be connected with-out overloading the input to the amplifier.

The MONO position of the input switch parallels theinputs of both amplifiers. When the outputs are prop-erly connected the MC 2100 becomes a 210 watt mono-phonic amplifier. The RIGHT/MONO GAIN control per-mits connecting signal sources up to 30 volts withoutoverloading the amplifier's input. To operate the MC2100 as a 210 watt monophonic amplifier the INPUTswitch must be in the MONO position and the OUTPUTmust be properly connected for monophonic opera-tion.

OUTPUTThe two barrier terminal strips marked LEFT OUT-

PUT and RIGHT OUTPUT provide stereo connectionsfor the normal speaker impedances of 4 ohms, 8 ohms,and 16 ohms, or monophonic operation connectionsfor 2 ohms, 4 ohms, and 8 ohms. The terminal stripsmay also be connected for a constant voltage outputof 25 volts in either stereo or mono.

OUTPUT (Octal Socket)The octal socket marked OUTPUT has stereo con-

nections for 4 ohms, 8 ohms, 16 ohms, and 25 volts.For monophonic operation the octal socket providesconnections for 2 ohms, 4 ohms, 8 ohms, and 25 volts.

FUSEThe MC 2100 uses a 5 ampere slo-blo type fuse. The

auxiliary AC outlet is not fused.

AC OUTLETThe auxiliary AC outlet can be used to supply power

to other equipment in the system. The outlet will pro-vide a maximum of 300 watts of power. The AC outletis not fused.

LINE VOLTAGEThe MC 2100 operates on any line voltage between

117 volts and 130 volts, 50 to 60 Hz.

4

LISTENING TO YOUR STEREO SYSTEMSETTING THE GAIN CONTROLS:

To set the GAIN controls for a stereo system use amonophonic signal from the program source. A mono-phonic signal supplies the same voltage to both chan-nels. Turn the volume control on the source equipmentto the 12 o'clock position {half rotation).

Turn up the LEFT GAIN control until the loudness

in the room is about as loud as you like to listen. Thenturn the GAIN control on the RIGHT INPUT until it isequally as loud as the left channel. The system is nowbalanced for loudness and provides the greatest rangeof operation and loudness change when using the vol-ume control on the source equipment.NOW SIT BACK AND ENJOY YOUR MclNTOSH

PERFORMANCE LIMITSPerformance Limits are the maximum deviation fromperfection permitted for a Mclntosh instrument. Wepromise you that the MC 2100 you buy must be capableof performance at or exceeding these limits or you getyour money back. Mclntosh is the only manufacturerthat makes this guarantee.

POWER OUTPUTSTEREO: 105 watts continuous, per channel, bothchannels operating, which is:

20.5 volts RMS across 4 ohms29.0 volts RMS across 8 ohms41.0 volts RMS across 16 ohms

MONO—210 watts continuous, which is:20.5 volts RMS across 2 ohms29.0 volts RMS across 4 ohms41.0 volts RMS across 8 ohms

HARMONIC DISTORTIONSTEREO Will not exceed 0.25% at any power levelto 105 watts output per channel from 20 Hz to 20,000Hz both channels operating. Typical performance isless than 0.1% at rated power. Distortion decreasesas output power is reducedMONO Will not exceed 0.25% at any power levelto 210 watts output from 20 Hz to 20,000 Hz. Typicalperformance is less than 0.1% at rated power. Dis-tortion decreases as output power is reduced

INTERMODULATION DISTORTIONSTEREO Will not exceed 0.25% if instantaneouspeak power is 210 watts or less per channel withboth channels operating for any combination of fre-quencies 20 Hz to 20,000 HzMONO Will not exceed 0.25% if instantaneous peakpower is 420 watts or less for any combination offrequencies 20 Hz to 20,000 Hz

FREQUENCY RESPONSE20 Hz to 20,000 Hz +0 -0.25 dB at rated power15 Hz to 60,000 Hz +0 —0.5 dB at rated power10 Hz to 100,000 Hz +0 -3.0 dB at one-half rated

powerNOISE AND HUM

90 dB or more below rated output

OUTPUT IMPEDANCESTEREO 4, 8, and 16 ohmsMONO 2, 4, and 8 ohms

OUTPUT VOLTAGES25 volts STEREO and MONO

DAMPING FACTOR20 at 4 ohms output14 at 8 ohms output11 at 16 ohms output

INPUT IMPEDANCE200,000 ohms

INPUT SENSITIVITY0.5 volt. Level control provided for higher input volt-

age

POWER REQUIREMENTS120 volts 50/60 Hz, 50 watts at zero signal output450 watts at rated output

SEMICONDUCTOR COMPLEMENT32 silicon transistors14 silicon rectifiers and diodes

MECHANICAL INFORMATIONSIZE: 7% inches high (19.69 cm), 11% inches wide

(29.85 cm), 17 inches deep (43.18 cm)CHASSIS: Chrome and black.WEIGHT: 57 pounds (25.86 kg) net, 63 pounds (28.58

kg) in shipping carton

SPECIAL FEATURESThe amplifier is completely stable when connected

to any loudspeaker system or even to any reactiveloads. The MC 2100 has special circuits to preventdamage by short circuit or open circuit of the outputloads, or by any amount of output impedance mis-match.

Thermal cutouts are mounted on the output tran-sistor heat sinks to provide protection in the event ofinadequate ventilation.

5

TECHNICAL DESCRIPTION

A two stage preamplifier with three transistors ineach channel increases the input voltage 16 dB.

There are 13 transistors in each power amplifier sec-tion. The two stage preamplifier is fed to a pair ofmatched transistors arranged as an emitter coupledamplifier with two inputs and one output. The signalfrom the preamplifier section connects to one of theseinputs. Both AC and DC negative feedback are appliedto the other input. This large quantity of feedback isused to reduce noise and distortion. The signal is thenfed to a voltage amplifier. The voltage amplifier is fol-lowed by two driver transistors.

The output section is arranged as a series push-pullamplifier. The power transistors used in the outputsection of your MC 2100 are selected for their highpower dissipation capability, wide frequency response,and large "safe operating area." In addition, eachpower transistor is given four separate tests before itis put in your MC 2100. This additional testing makessure your MC 2100 will deliver its rated power from20 Hz to 20 kHz with low distortion and complete reli-ability.

The power transistors are mounted on oversizedanodized heat sinks. The heat sinks assure that undernormal operation the transistors will operate at a lowtemperature. If temperatures increase due to a shortedspeaker, or restricted ventilation, an automatic tem-perature sensing device turns off the MC 2100. Thedevice operates automatically at a preset temperature.The MC 2100 will turn on again when the temperaturehas returned to normal limits. This additional featuregives your MC 2100 complete reliability under the mostextreme operating conditions.

The output stages are matched to the load by theMclntosh autoformer. The Mclntosh autoformer is care-fully wound using Mclntosh trifilar winding and inter-leaving techniques. Trifilar winding and interleavinggives the autoformers exceptional bandwidth. Theautoformers properly match the power transistors to4, 8, and 16 ohm loads at all audio frequencies.

The use of the Mclntosh designed trifilar autoformermakes the Mclntosh solid state amplifiers the onlyamplifiers that deliver FULL POWER AT ALL SPEAKERIMPEDANCES. You have not been power penalized foryour choice of loudspeakers when using the MclntoshMC 2100.

Another of the advantages of the autoformers is the25 volt output for a constant voltage distribution sys-tem. With the MC 2100 several sets of speakers can beoperated independently throughout your home.

To further insure reliability a special power outputSENTRY MONITORING CIRCUIT prevents failure ofthe power output transistors due to excessive mis-

match of the output. When your MC 2100 operates nor-mally the SENTRY MONITORING CIRCUIT has noeffect on signals passing through the power amplifier.If the power dissipation should rise above normal op-eration, the SENTRY MONITORING CIRCUIT restrictsthe drive to the output transistors. The SENTRY MON-ITORING CIRCUIT acts instantaneously for any inputsignal or load combination. This arrangement assurescomplete circuit reliability. Only Mclntosh gives youthis degree of protection.

There are three separate power supply sections. Onepositive and one negative high current supply is usedfor the output stages. The other positive supply is usedfor the driving amplifier stages. All supplies are fullwave and use silicon rectifiers. Adequate filtering isused to assure an absolute minimum of hum. Thepower output stage filter capacitors have very highcapacity, which allows full power output below 20 Hz.The power transformer is generous in size and runscool, even under heavy use.

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MclNTOSH LABORATORY INC.

2 CHAMBERS ST., BINGHAMTON, N. Y. 13903607-723-3512

Design subject to change without notice.Printed in U.S.A.

038-663

BE022004