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. Failure of a fuse is usually an indication of a problem. Replacing the fuse, if there is problem in the amplifier, may incur a risk of further damage. Refer to figures 10, 11 and 12.

Caution: Disconnect the Amplifier from the Vehicle Battery

(or DC Power Supply) as Potentially Dangerous Currents exist inside the amplifier.

1.Before accessing fuses, disconnect both the positive and negative power cables from the DC input terminals on the left side of the amplifier using a 5/32” hex key.

2.Remove the Top Glass Panel by first removing the four hex bolts with the supplied 3/32” hex key.

3.To remove the Top Glass Panel, 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.

4.Remove the Phillips Screws holding the End Caps on both sides of the amplifier and lift the end caps off.

5.Remove the two Phillips screws located between the low and high pass filter controls.

6.Remove all 12 crossover, equalizer and sensitivity knobs.

7.Remove the Gold Faceplate Control Panel.

8.Remove the fuses with needle nose pliers, taking care to avoid hitting the wattmeter during removal. Do not lever the pliers against the wattmeter.

Note: To determine if the fuse has failed, examine the link between the two fuse legs to see if it has a break in it.

9.Replace the fuse with one of the same type and rating as unauthorized substitutions may prove hazardous to you and the amplifier.

10.When reinserting the fuse, set it in place with the pliers, then push it the rest of the way in with your finger to avoid having the pliers slip and hit the circuit board.

11.Re-install the Gold Faceplate Control Panel and all 12 crossover, equalizer and sensitivity knobs.

12.Re-connect the power cables to the vehicle battery. If the replacement fuse(s) fails again, have the amplifier repaired at a McIntosh Service Center.

Remove Top Cover Screws

Figure 10

Remove Top Cover Screws

Remove Three Screws

Figure 11

Remove Three Screws

Location of the four fuses

Figure 12

MCC406M specifications

The McIntosh MCC406M is a high-performance mono audio amplifier that epitomizes the luxurious craftsmanship and cutting-edge technology for which McIntosh is renowned. Designed for audiophiles who demand the utmost in sound quality and power, the MCC406M stands out with its impressive specifications and features.

One of the primary characteristics of the MCC406M is its robust power output. It delivers a staggering 400 watts of continuous power into a 2-ohm load, ensuring that it can drive even the most demanding speakers effortlessly. The amplifier operates with a high damping factor, which permits precise control of the speaker's performance, yielding tighter bass and enhanced overall fidelity.

The MCC406M incorporates advanced technologies that ensure optimal performance and reliability. At the heart of the amplifier is the McIntosh patented Autoformer, which allows it to deliver the same output power regardless of the speaker’s impedance, be it 2, 4, or 8 ohms. This feature not only enhances compatibility with a wide range of speakers but also ensures consistency in audio performance.

Another notable technology is the Power Guard® system, which monitors and adjusts the amplifier's output to prevent clipping and distortion, safeguarding both the amplifier and connected speakers. This feature is crucial for maintaining sound integrity even at high listening levels, allowing for an enjoyable and reliable listening experience.

In terms of design, the MCC406M embodies McIntosh’s signature aesthetic with its sleek black glass front panel, illuminated logo, and glowing watt meters, which provide a visual representation of the output power. This sophisticated appearance makes it a standout piece in any audio system.

Additionally, the MCC406M features a balanced audio input and a variety of connections, accommodating different setups and ensuring maximum compatibility with various preamplifiers. Its compact design also allows for versatility in placement, whether in a dedicated audio room or a living space.

Overall, the McIntosh MCC406M amplifier combines powerful performance, advanced technologies, and elegant design, making it a premium choice for those seeking to elevate their audio experience. Whether for music appreciation or home theater applications, this amplifier delivers exceptional sound quality, embodying the McIntosh legacy of excellence.