User manual MCINTOSH MA6900

[. . . ] Integrated Amplifier MA6900 Owner's Manual McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 13903-2699 Phone: 607-723-3512 FAX: 607-724-0549 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. To prevent the risk of electric shock, do not remove cover or back. No user serviceable parts inside. IMPORTANT SAFETY INSTRUCTIONS! PLEASE READ THEM BEFORE OPERATING THIS EQUIPMENT. 1. [. . . ] Refer to figure 4. Figure 4 Balance Control Adjust the BALANCE control as needed to achieve approximately equal listening volume levels in each loudspeaker. Turn the BALANCE to the left to emphasize the Left Channel by reducing the level of the Right Channel. Turn the BALANCE to the right to emphasize the Right Channel by reducing the level of the Left Channel. Equalizer Controls Each of the five Equalizer Frequency Controls will raise or lower by approximately12dB, the amplitude of the band of frequencies centered at the frequency marked above the controls. At the center detent or flat position of the controls, all equalizer circuit components are removed from the signal path. Source Selection Select the desired source with the appropriate pushbutton switch on the Front Panel or Remote Control. Volume Control Adjust the VOLUME control for the desired listening level. Figure 2 Figure 5 Loud Switch Press the LOUD push-button to add loudness bass compensation to the volume control for improved low level listening. Mono Press the MONO push-button to combine left and right stereo signals to mono at the SPEAKERS 1 and 2 and HEADPHONES output. Mute Press the MUTE push-button to mute audio in all outputs except the HEADPHONES and TAPE OUTPUT. The MUTE LED above the push-button will flash on and off to indicate that Mute is active. To unmute audio, press MUTE, press the Remote Control Volume push-button(s) or press an Input push-button. 13 Figure 3 How to Operate, con't Outputs 1 and 2 Press OUTPUTS Push-button 1 to switch the Speakers On or Off. The push-buttons also switch the Preamplifier OUTPUTS 1 Figure 6 and 2 On or Off for connection to external Power Amplifier(s). Headphones Jack Connect a pair of dynamic headphones to the Headphones Jack for private listening. Press Mute to mute all other outputs including the amplifier connected to the loudspeakers. Reset of Microprocessors In the event that the controls of the MA6900 stop functioning, push the POWER switch OFF and wait about two minutes. Then push the POWER switch ON followed by pushing the STANDBY/ON push-button. This will reset the MA6900 microprocessors and the Integrated Amplifier should be functioning normally. Note: The above condition is usually caused by either interruptions in AC power and/or major changes that may occur in AC power line voltage. How To Make A Tape Recording 1. Select the source signal you wish to record with the appropriate Front Panel input push-button. If you wish to record from an Audio/Video source connected to the optional McIntosh Audio/Video Selector Audio/Video Selector, using the Remote Control, select the desired source connected to the McIntosh Audio/Video Selec- Figure 9 tor. Adjust the record level using the tape recorder volume control and proceed with the recording process. To listen to the tape playback of the program source just recorded, press the TAPE input push-button. Note: The MA6900 TAPE OUTPUTS are not affected by the VOLUME or BALANCE controls. Power Output Meters The MA6900 Power Output Meters indicate the power delivered to the loudspeakers. The meters respond to all the musical information being produced by the amplifier. They indicate to an accuracy of at least 95% of the power output with only a single cycle of a 2000Hz tone burst. Using a Separate Power Amplifier There are two different ways to use a separate power amplifier with a MA6900. The first way is to use the separate amplifier instead of the MA6900 built-in Power Amplifier. [. . . ] When the difference exceeds 0. 3% (equivalent to 0. 3% harmonic distortion), the Power Guard activates the Top Inside View of the MA6900 ance 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 MA6900 contributes to low operating temperatures. More than 621 square inches of heat sink area keep the MA6900 operating safely with convection cooling. [. . . ]