HD1801

Placement

As mentioned in the previous two pages, HD1801 subwoofers may be flown. However, they are designed to sit on the floor or stage, as well. A socket is

provided on top of the HD1801 for mounting other Mackie loudspeakers. Use a suitable speaker mounting pole to mount them on the HD1801. See the hookup diagrams starting on page 4.

Check to make sure that the support surface (e.g., floor, etc.) has the necessary mechanical characteristics to support the weight of the loudspeaker(s) and subwoofer(s).

When pole-mounting loudspeakers, be sure that the HD1801 subwoofers are stabilized and secured from falling over or being accidentally pushed over. For stacked scenarios, it is highly suggested that straps are utilized. Failure to follow these precautions may result in damage to the equipment, personal injury, or death.

As with any powered components, protect them from moisture. Avoid installing the subwoofer in places exposed to harsh weather conditions. If you are setting them up outdoors, make sure they are under cover if you expect rain.

Thermal Considerations

The HD1801 has a powerful built-in amplifier capable of producing 800 watts of rms power. As an amplifier works, it produces heat. The higher the signal level, the louder and hotter it gets. It is important to dissipate the heat as quickly as possible. This results in increased reliability and longevity for the amplifier.

The amplifier module is cooled by twin thermally-controlled vari-speed fans. In order for this cooling system to work efficiently, it is important to provide adequate airspace behind the subwoofer. When positioning the HD1801, we recommend leaving at least six inches of air space behind it.

In the unlikely event of the amplifier overheating, a built-in thermal switch will activate, muting the amplifier’s output. When the amplifier has cooled down to a safe operating temperature, the thermal switch resets itself, and the HD1801 resumes normal operation.

If the thermal switch activates frequently, try turning down the level control a notch or two on the mixing console (or the back of the HD1801) to avoid overheating the amplifier. Be aware that direct sunlight and/or hot stage lights may be the cause of an amplifier overheating.

AC Power

Be sure the HD1801 is plugged into an outlet that is able to supply the correct voltage specified for your model. It will continue to operate at lower voltages, but will not reach full power.

Be sure the electrical service can supply enough amperage for all the components connected to it.

We recommend that a stiff (robust) supply of AC power be used because the amplifier places high current demands on the AC line. The more power that is available on the line, the louder the subwoofer will play and the more peak output power will be available for a cleaner, punchier bass. A suspected problem of “poor bass performance” is often caused by a weak AC supply to the amplifier.

Never remove the ground pin on the power

cord or any other component of the HD1801. This is very dangerous.

Care and Maintenance

Your Mackie subwoofers will provide many years of reliable service if you follow these guidelines:

•Avoid exposing the subwoofers to moisture. If they are set up outdoors, be sure they are under cover if rain is expected.

•Avoid exposure to extreme cold (below freezing temperatures). If you must operate the subwoofers in a cold environment, warm up the voice coils slowly by sending a low-level signal through them for about 15 minutes prior to high-power operation.

•Use a dry cloth to clean the cabinets. Only do this when the power is turned off. Avoid getting moisture into any of the openings of the cabi- net, particularly where the driver is located.

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HD1801