Technical Description
Technical Description
McIntosh Laboratory, the company who introduced the world’s first amplifier over fifty years ago that could be called “High Fidelity”, has done it again. The McIntosh engineering staff has created a power amplifier without compromise, using the most advanced McIntosh circuit design concepts.
A continuous average power output rating of 300 watts and with an output current of greater than 50 amperes per channel, makes this not only the most advanced, but also the most powerful amplifier McIntosh has ever manufac- tured. The distortion limits for the MCC602TM are no more than 0.005% at rated power output for all frequen- cies from 20Hz to 20,000Hz. Typical performance at mid frequencies is less than 0.002%. The true distortion read- ings on the MCC602TM are so low, it takes special mea- suring techniques to make accurate readings. The MCC602TM can deliver the best possible performance 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 measuring 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 MCC602TM involved several different techniques, all based on sound scientific logic. Every stage of voltage or current amplifi- cation must be as linear as possible prior to the use of negative feedback. McIntosh engineers know how to prop- erly design negative feedback circuits so they contribute to
the extremely low distortion performance expected from a McIntosh amplifier. The typical McIntosh owner would never accept the approximately 100 times higher distortion of many
Double Balanced Push Pull design is used from input to output. Each half of the amplifier contains complimentary balanced circuitry. The resulting double balanced configu- ration cancels even order distortion. Refer to figure 11 on page 18.
All transistors are selected to have nearly constant cur- rent gain over the entire current range they must cover. Output transistors in particular, have matched uniform cur- rent gain, high
The output signals of the two balanced circuits are coupled together in the unique McIntosh MCC602TM Out- put Autoformer. It provides low distortion power transfer at frequencies from below 20Hz to well beyond 20,000Hz with optimum impedance points of two ohms, four ohms and eight ohms. The unequaled expertise of McIntosh in the design and manufacturing of autoformers is legendary in the high fidelity industry.
The high efficiency circuit design of the MCC602TM contributes to low operating temperatures. McIntosh ampli- fiers are constructed in an extruded aluminum tunnel that has exhaust ports along its length. These exhaust ports are tuned to provide even air flow, over the surface of the tun-
Inside the MCC602TM
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