McIntosh MC-501

Offer is for a pair of pefect amplifiers
MC-501 is a solid-state 500 watt monoblock that is capable of putting out a continuous 500 watts into eight, four, or two Ohms and peaks of up to 1,200 watts, which is a great deal of power for their price of $11,000 per pair. Unique to McIntosh is the use of the output autoformer. The output autoformer is said to match various speaker impedance levels to the amplifier circuits, keeping the amplifier operating within its optimum load, reducing distortion and overheating. The MC-501's fully balanced quad-differential circuits go beyond a traditional balanced circuit topology to eliminate nearly all distortion. Total harmonic distortion is rated at less than 0.005 percent at rated power, as is intermodulation distortion. The amplifier is protected by two systems, McIntosh's Power Guard which prevents the amplifier from being overdriven and Sentry Monitor with Thermal Protection.
All of the performance and protection features are wrapped up in a chassis that is immediately identifiable at great distance as a McIntosh. The MC-501 has the signature black glass front panel with a very large illuminated power meter with soft blue backlighting above the iconic McIntosh logo which is backlit by green fiber optics. The panel features McIntosh's new "three dimensional look" which adds a modern touch to this classic design. Chrome plated knobs can be found below and to each side of the illuminated meter. One controls the meter allowing the meter to operate in real time, hold on peaks or be turned off when a dark room is desirable, the other knob turns the amplifier on and off or allows for remote triggering. This amplifier looks just as impressive from any angle; the bottom portion of the amplifier is made from stainless steel polished to chrome like appearance upon which two large enclosures sit directly behind the front panel, one for the transformer and the other the autoformer. Heavy vertical fins run from the transformer and autoformer to within a couple of inches of the back of the amplifier, the horizontal space between the fins and the back of the amplifier is where the three sets of large, custom made speaker taps, a three prong IEC power cord port, control ports, balanced and single ended inputs with a switch to choose the active input. The whole package measures a compact 17 and a half inches wide, by nearly nine inches high and almost 15 inches deep and weighs in at a hefty 92 pounds.
The MC-501's build quality is first rate.
I have all original boxes and manuals. These are perfect in every way.