User manual MCINTOSH SCR2 SERVICE MANUAL

[. . . ] Warning: This unit is capable of producing high sound pressure levels. Continued exposure to high sound pressure levels can cause permanent hearing impairment or loss. User caution is advised and ear protection is recommended when playing at high volumes. Route DC power cords so that they are not likely to be pinched by items placed upon or against them, paying particular attention to the point where they enter the 11. [. . . ] The preferred installation method is to mount the amplifier directly to the vehicle main frame using the hardware supplied with the amplifier. It is not recommended that the amplifier be mounted under the hood or in a location where it will be directly exposed to the elements. The openings in the fan housings and heat tunnel vents can allow internal components to be damaged by exposure to water, chemicals or any form of road dust or debris. Removing the Glass Panel To access the MCC406M Controls, remove the glass panel by removing the four hex bolts with the supplied 3/32" hex key. Attach the supplied suction cup to the top center of the glass panel and carefully raise it high enough to put your hand under. Temporarily place the removed glass panel in a safe place, remove the suction cup and save it for future use. Removing the End Caps To access the MCC406M Connecting Terminal Blocks, remove the Glass Panel first (the above step) and then remove the Phillips Screws holding the End Caps on both sides of the amplifier and lift the end caps off. See figure 3. Cool Air Warm Air Figure 1 Cool Air Warm Air Remove Top Cover Screws Figure 2 Remove Top Cover Screws Remove End Cap Screws Figure 3 Remove End Cap Screws 6 Side Panel Cooling and Connections Connect to the Negative (-) vehicle battery terminal Cooling Fan Air Intake Connect to the positve (+) vehicle battery terminal with an inline fuse Cooling Fan Air Intake INPUTs for audio cables from a signal source Receives the Amplifier Turn-ON signal from a McIntosh Control Center Connector for optional Subwoofer Remote Volume Control OUTPUT Connections for 2, 4 or 8 ohm loudspeakers OUTPUT Connections for 2, 4 or 8 ohm loudspeakers Controls the Power Guard Circuit when connected to certain McIntosh Control Centers 7 How to Connect for Six Channels 1. Connect a cable from the Control Center Amp On to the MCC406M ON Connector on the right side of the amplifier. Note: All cables should be connected to the amplifier before connecting the DC power cables to the battery. 2. Connect a cable from a McIntosh Control Center with Power Guard to the MCC406M PG Connector on the right side of the amplifier. Connect cables (up to 12 AWG) from six separate Loudspeaker Drivers to the MCC406M Power Amplifier Channels 1, 2, 3, 4, 5 and 6 Terminals, being careful to observe the correct polarities. Low Pass Filter The LOW PASS Filter Controls select the frequencies at which the filters operate. Any given frequency number is selected through the combined settings of the FREQUENCY and MULTIPLIER controls. The low-pass filters multiplier switches have settings of X1 (frequency times one), X10 (frequency times ten). Refer to figure 4. Figure 4 Example: A frequency 1, 500 Hz would be attained by setting the FREQUENCY Control to 150 and setting the MULTIPLIER Switch to X10 (150 times 10 equals 1, 500). owner's manual. The Level controls can be set for any sensitivity from . 5 volts to 8 volts. Refer to figure 6. Note: When used in conjunction with a McIntosh control center, you may find setting the Sensitivity controls to the center detent (1. 5V) works best. Figure 6 Power Output Meters There are two illuminated watt meters on the glass panel, the left meter displaying combined power output for channels 1, 2, 3 and 4 and the right meter displaying combined power output for channels 5 and 6. The upper scale shows power in watts during normal operation, the lower scale displays power in watts for bridged operation. The meters respond to all the musical information being produced by the amplifier. High Pass Filter The HIGH PASS Filter Controls select the center frequencies at which the filters operate. Any given frequency number is selected through the combined settings of the FREQUENCY and MULTIPLIER controls. The high-pass filter multiplier switches have settings of X. 1 (frequency times one-tenth), X1 (frequency times one), X10 (frequency times ten). Refer to figFigure 5 ure 5. Example: A frequency of 15 Hz would be selected by setting the FREQUENCY Control to 150 and the MULTIPLIER Switch to X. 1 (150 times . 1 equals 15). Figure 7 They indicate to an accuracy of at least 95% of the power output with only a single cycle of a 2000Hz tone burst. [. . . ] This will send frequencies above 100Hz to the upper range speakers for channels 1 thru 4 and roll-off frequencies below 5Hz for channels 5-6. Set the Channel 5-6 Low Pass Filter FREQUENCY Control to 100 and the MULTIPLIER Switch to X1. This will roll-off frequencies above 100Hz for channels 5-6. Figure 9 17 How to Replace the Fuses How to Replace the Fuses If the MCC406M produces no sound, there is no Illumination of the Nomenclature on the Top Glass Panel, and the power connections seem secure, one or more of the Amplifier Fuse(s) may have failed. Under normal operating conditions your amplifier's fuses should not fail. [. . . ]