User manual MCINTOSH MC75

[. . . ] McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 13903-2699 Phone: 607-723-3512 www. mcintoshlabs. com MC75 60th Anniversary Tube Power Amplifier Owner's Manual The lightning flash with arrowhead, within an equilateral triangle, is intended to alert the user to the presence of uninsulated "dangerous voltage" within the product's enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons. The exclamation point within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in the literature accompanying the appliance. WARNING - TO REDUCE RISK OF FIRE OR ELECTRICAL SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL. third grounding prong. The wide blade or the third prong are provided for your safety. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet. [. . . ] 10-11 Left Side Panel Display and Switches . . . . . . . . . . . . . . . . . . . . . . 12 How to Operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Packing Instruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Technical Assistance If at any time you have questions about your McIntosh product, contact your McIntosh Dealer who is familiar with your McIntosh equipment and any other brands that may be part of your system. If you or your Dealer wish additional help concerning a suspected problem, you can receive technical assistance for all McIntosh products at: McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 13903 Phone: 607-723-1545 Fax: 607-724-0549 6 5. When discarding the unit, comply with local rules or regulations. Batteries should never be thrown away or incinerated but disposed of in accordance with the local regulations concerning battery disposal. For additional information on the MC75 and other McIntosh Products please visit the McIntosh Web Site at www. mcintoshlabs. com. Note: The impedance of a Loudspeaker actually varies as the Loudspeaker reproduces different frequencies. As a result, the nominal impedance rating of the Loudspeaker (usually measured at a midrange frequency) might not always agree with the impedance of the Loudspeaker at low frequencies where the greatest amount of power is required. Contact the Loudspeaker Manufacturer for additional information about the actual impedance of the Loudspeaker before connecting it to the McIntosh MC75. Copyright 2009 © by McIntosh Laboratory, Inc. General Information, Cable Information, Introduction and Performance Features Connector and Cable Information Performance Features · Power Output The MC75 is a Tube Power Amplifier with a capability of 75 watts into 2, 4 or 8 ohm speakers with less than 0. 5% distortion. · Unity Coupled Circuitry The MC75 Power Amplifier uses the famous McIntosh Patented Unity Coupled Circuit which provides low distortion, extended frequency response and cool operating output tubes. · Multifilar Wound Output Transformer The MC75 Output Transformer Windings are part of the Unity Coupled Circuitry. There are two bifilar wound primaries, one for the cathodes and one for the plates. The secondary winding is wound together with the primary windings. This provides very close primary to secondary coupling. The result is flat frequency response and wide power bandwidth. · Balanced and Unbalanced Input Balanced connections guard against induced noise and allow long cable runs without compromising sound quality. · Sentry Monitor Tube Protection McIntosh Sentry Monitor Tube Protection Circuits ensure the MC75 will have a long and trouble free operating life. · Gold Plated Connectors and Tube Socket Contacts Gold Plated Input Jacks and Output Binding Posts provide trouble free connections. Ceramic tube sockets with gold plated contacts provide protection from atmospheric contamination. Output Tube Sockets include Air-Pipe cooling at their bases. [. . . ] It will also activate if there is a short circuit at the MC75 Output Terminals (or the Loudspeaker Terminals) or if a MC75 Power Output Tube should fail. During normal operation the Sentry Monitor Tube Protection Circuitry has no effect on the performance of the Power Amplifier. In the event a problem occurs, the MC75 Sentry Monitor Tube Protection Circuitry will activate to prevent potentially destructive high levels of current from flowing in the amplifier. The Front Panel Standby LED will start flashing indicating the Protection Circuitry has activated and the AC Power to the MC75 is halted. [. . . ]