User manual MCINTOSH MC240

[. . . ] All this occurs without the crossover distortion found in conventional solid state output circuits. (The amplifier circuit is a patented McIntosh design U. S. patent #3526847. ) The McIntosh output stages are mounted on heat sinks that have 772 square inches of cooling capability, the largest for equivalent power in the industry. The super sized heat sinks are placed in an air tunnel chassis design that occupies the entire space from the bottom of the amplifier to the top. MCINTOSH QUALITY BEGINS WITH CAREFUL DESIGN FOR COOL OPERATION To achieve long trouble-free life in an amplifier it is essential to have cool operation. [. . . ] Even if the meter were capable of such high velocity movement, the human eye could not perceive the information. McIntosh engineering solved both problems electrically. By developing new electronic circuits the meters are made to respond to short intervals with an accuracy of 98%!To permit the eye to see such high speed motion, the electronic circuits that drive the meter pointer are time stretched so the meter pointer position can register in the persistence of vision characteristics of the human eye. The peak-reading, peaklocking meter circuit is a patented McIntosh design (U. S. A variety of information can be displayed on the meters. You may elect to observe the delivered power in watts demanded by the musical program or you may elect to lock and hold only the highest power indications yet have continuous updating as higher powers are delivered or you may select from three different peak-reading, peak-locking decibel indications. Each selected function is indicated by illuminated nomenclature on the panel. THE MCINTOSH "ALWAYS IN STYLE" The appearance of a McIntosh speaks eloquently of precision, quality, premier performance and long, trouble-free life. Consider the construction and materials used in the front panel and knobs. Each constituent part is selected for long, wear-resistant life and stable attractive styling. The panel of the MC 2155 is select glass, free from bubbles, flow marks and other faults. A heat sensing switch attached to the super sized heat sinks controls the AC power to the amplifier. As long as temperatures are normal it does not function; but, should the temperature of the heat sinks rise above normal, the AC power is disconnected automatically until the temperature returns to normal when the AC power is restored. In ordinary solid state circuits failure in the output stage can cause damaging direct current components to flow to the loudspeakers. With the McIntosh autotransformer, matching the output circuits to the loudspeakers, any direct current component is shunted to ground. Your speakers are protected completely from this kind of amplifier failure. McIntosh gives you a moneyback performance guarantee. We promise you that when you purchase a new McIntosh from a McIntosh franchised dealer, it will be capable of or can be made capable of performance at or exceeding its published performance limits or you can return the instrument and get your money back. McIntosh is the only manufacturer that makes this statement. McIntosh protects your listening and your investment. To assure you of the McIntosh belief in design for long life, McIntosh goes beyond the ordinary guarantee. You are offered a McIntosh 3 Year Service Contract which protects you from the cost of repair for three full years. [. . . ] Your expensive loudspeakers are protected from this potentially damaging circumstance. A third benefit of the McIntosh autotransformer, which not only provides the output transistors an ideal load and is the path that conducts any DC away from the loudspeaker, also contributes a flexibility in loudspeaker connecting capability not otherwise possible. For safe operation ordinary amplifier output circuits are usually restricted to operate into 4 or 8 ohms. In stereo, the McIntosh autotransformer perfectly matches the output circuit to 1, 2, 4 or 8 ohms. [. . . ]