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Technical Description

McIntosh Laboratory, the company who introduced the
world’s first amplifier that could be called “High Fidelity”,
has done it again. The McIntosh engineering staff has cre-
ated a power amplifier without compromise, using the most
advanced McIntosh circuit design concepts.

A continuous average power output rating of 250 watts

and with an output current of greater than 50 amperes per
channel, making this one of the most advanced and power-
ful amplifiers McIntosh has ever manufactured. The distor-
tion limits for the MC252 are no more than 0.005% at rated
power output for all frequencies from 20Hz to 20,000Hz.
Typical performance at mid frequencies is less than
0.002%. The true distortion readings on the MC252 are so
low, it takes special measuring techniques to make accurate
readings. The MC252 can deliver the best possible perfor-
mance from any type of high quality loudspeaker system.

Creating an amplifier with this level of performance did

not come easily. Many months of design, testing and mea-
suring were required. Extensive controlled listening tests,
the ultimate form of measuring, were made before the final
design was accepted.

Design Philosophy

The design philosophy incorporated in the MC252 in-
volved several different techniques, all based on sound sci-
entific logic. Refer to figure 14. Every stage of voltage or
current amplification must be as linear as possible prior to
the use of negative feedback. McIntosh engineers know
how to properly design negative feedback circuits so they
contribute to the extremely low distortion performance ex-
pected from a McIntosh amplifier. The typical McIntosh
owner would never accept the approximately 100 times
higher distortion of many non-feedback designs.

All transistors are selected to have nearly constant cur-

Inside View of the MC252

Содержание MC252

Страница 1: ...MC252 Owner s Manual McIntosh Laboratory Inc 2 Chambers Street Binghamton New York 13903 2699 Phone 607 723 3512 FAX 607 724 0549 Power Amplifier...

Страница 2: ...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 prov...

Страница 3: ...x 607 723 3636 Table of Contents Important Information Caution The MC252 Amplifier weight is 94 5 pounds 42 87 kilograms It requires two or more persons to safely handle when moving the amplifier 1 Th...

Страница 4: ...mponents Positive N C Ground Balanced and Unbalanced Inputs Balanced connections guard against induced noise and al low long cable runs without compromising sound quality Patented Sentry Monitor with...

Страница 5: ...MC252 There is additional informa tion on the next page pertaining to installing the MC252 into cabinets 17 1 2 44 45cm 8 13 16 22 38cm Front View of the MC252 Rear View of the MC252 Side View of the...

Страница 6: ...fier If all the components are in stalled in a single cabinet a quiet running ventilation fan can be a definite asset in maintaining all the system components at the coolest possible operating tempera...

Страница 7: ...se holder refer to information on the top back panel of the MC252 to determine the cor rect fuse size and rating POWER CONTROL IN receives a turn On Off Trigger from a McIntosh component POWER CONTROL...

Страница 8: ...l so the wires cannot slip out Refer to figures 4 5 6 Banana plug connection Insert the banana plug into the hole at the top of the terminal Tighten the top portion of the terminal post and the set sc...

Страница 9: ...9 How to Connect in Stereo To AC Outlet 4 ohm Loudspeaker McIntosh C45 Audio Control Center MC252 Top Rear View 4 ohm Loudspeaker...

Страница 10: ...or banana connector Spade lug or prepared wire connection Insert the spade lug connector or prepared section of the cable end into the terminal side access hole and tighten the terminal cap until the...

Страница 11: ...okup Connections Loudspeaker Impedance Loudspeaker Negative Connection Loudspeaker Positive Connection 4S Ohm Left Output 2S Positive Connection Right Output 2S Positive Connection 8S Ohm Left Output...

Страница 12: ...r to figures 1 2 3 If the cable wire is stranded carefully twist the strands together as tightly as possible Note If desired the twisted ends can be tinned with solder to keep the strands together or...

Страница 13: ...Outlet 4 ohm Loudspeaker McIntosh C45 Audio Control Center MC252 Top Rear View Jumper Wires additional instruction on making Loudspeaker Connections contact your McIntosh Dealer or McIntosh Technical...

Страница 14: ...er POWER GUARD LED lights when the amplifier Right Channel POWER GUARD circuit activates POWER Switch Turns AC power On Off or On Remote Remote On Indicator lights when the amplifier is in the Remote...

Страница 15: ...e of a 2000Hz tone burst Hold The meter pointer is locked to the highest power peak in a sequence of peaks It is elec tronically held to this power level until a higher power peak passes through the a...

Страница 16: ...The MC252 can deliver the best possible perfor mance from any type of high quality loudspeaker system Creating an amplifier with this level of performance did not come easily Many months of design te...

Страница 17: ...000Hz with optimum imped ance points of two ohms four ohms and eight ohms The unequaled expertise of McIntosh in the design and manu facturing of autoformers is legendary in the high fidelity industr...

Страница 18: ...omise in sonic perfor mance with this circuit and it ensures safe op eration of the amplifier under even the most extreme operating condi tions The different types of protection circuits incorpo rated...

Страница 19: ...MC252 is equipped with a circuit that provides remote Power Control from Figure 20 Block Diagram of the Power Supply your McIntosh Preamplifier or Control Center When you turn on your preamplifier a...

Страница 20: ...20...

Страница 21: ...21 Notes...

Страница 22: ...on Distortion if instanta neous peak output per channel does not exceed twice the rated output for any combination of fre quencies from 20Hz to 20 000Hz with all channels operating is 0 005 Dynamic He...

Страница 23: ...he equipment must be packed exactly as shown below It is very important that the four plastic feet are at tached to the bottom of the equipment Three 10 x 2 1 2 inch screws and washers must be used to...

Страница 24: ...ntosh Laboratory Inc 2 Chambers Street Binghamton NY 13903 The continuous improvement of its products is the policy of McIntosh Laboratory Incorporated who reserve the right to improve design without...

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