Technical Description, con’t

tronic attenuator at the amplifier input reduces the input volume just enough to prevent any further increase in dis- tortion. The Power Guard circuit acts so fast that there are absolutely no audible side effects and the sonic purity of the music reproduction is perfectly preserved. The MC252 Power Amplifier with Power Guard is not limited to just the rated power output, but will actually produce distortion free output well above its rated power due to the McIntosh philosophy of conservative design.

Power Supply Circuits

To compliment the design of the MC252, there is a high voltage power supply for both channels. Refer to figure 20. The power amplifiers draw high current from the AC power line. Therefore, it is important that they plug directly into the wall outlet.

Also, most owners desire that there be one power switch for the whole audio system. The MC252 is equipped with a circuit that provides remote Power Control from

your McIntosh Preamplifier or Control Center. When you turn on your preamplifier a digital “1” (+5V) signal oper- ates the power relay in the MC252. The MC252 also has a remote Power Control Out Jack. The Power Control signal from this jack is delayed by a fraction of a second so that the turn on power surge of the next power amplifier occurs at a later time. This helps prevent power circuit overload that could trip circuit breakers or blow fuses, a very impor- tant feature in a high power Home Theater System employ- ing three MC252 Power Amplifiers.

The MC252 can provide greater than 50 amperes peak output current to drive uneven speaker loads. Some poor speaker designs have input impedance that dip to 1 or 2 ohms at various frequencies and the MC252 has the output current reserve to drive them. The MC252 has main filter capacitors that guarantee an excellent signal to noise ratio and the energy storage necessary for the wide dynamic range that “Digital Audio” demands.

Block Diagram

of the

Power Supply

Figure 20

19

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Image 19
McIntosh MC252 owner manual Technical Description, con’t

MC252 specifications

The McIntosh MC252 is a legendary power amplifier known for its innovative approach to high-fidelity audio reproduction. As a part of McIntosh's esteemed lineup, this amplifier embodies the company's commitment to exceptional sound quality and timeless design.

One of the standout features of the MC252 is its dual mono design. This architecture not only enhances stereo imaging but also reduces crosstalk, providing a cleaner and more defined soundstage. Each channel operates independently, ensuring that each speaker receives precise and stable power, ideal for discerning audiophiles who demand the highest quality in their audio systems.

The MC252 is rated to deliver 250 watts per channel into 8 ohms, with a powerful peak at 300 watts into 4 ohms. This robust output makes it suitable for driving a wide range of speakers, from efficient bookshelf models to large floor-standing designs. The amplifier is designed to handle dynamic music and movie soundtracks with ease, delivering an engaging listening experience without distortion.

McIntosh's patented Power Guard technology is another hallmark feature of the MC252, designed to prevent clipping and distortion. This intelligent system monitors the output signal and automatically adjusts the power levels, ensuring the integrity of the audio signal is maintained even at high volumes. This feature guarantees that listeners can enjoy their music without fear of damaging their speakers.

The amplifier also incorporates a unique input and output circuitry that adheres to McIntosh’s time-honored values of craftsmanship and quality. The iconic blue watt meters not only serve a practical purpose, providing real-time feedback on power output but also add to the visual appeal of the unit, making it a centerpiece in any audio setup.

In terms of build quality, the MC252 features durable, high-quality aluminum and glass components that define McIntosh’s aesthetic. This attention to detail ensures longevity and a classic look that never goes out of style.

Overall, the McIntosh MC252 stands as a testament to the evolution of audio technology, offering robust performance, cutting-edge features, and a design ethos that honors tradition while embracing modernity. For audiophiles seeking a high-performance amplifier that delivers both power and finesse, the MC252 remains a compelling choice. Whether for home theater or music listening, its capabilities ensure an exceptional audio experience, making it a prized possession for any serious audio enthusiast.