7

AC POWER

Be sure the SWA2801z is plugged into
an outlet that is able to supply the correct
voltage specied for your model. If the volt-
age should drop below 97% of the specied
line voltage, the built-in ampliers will no
longer be able to supply rated power. (They
will continue to operate down to 80% of
the rated line voltage, but won’t reach full
power, resulting in lower headroom.)
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
ampliers place high current demands on
the AC line. The more power that is avail-
able on the line, the louder the speakers
will play and the more peak output power
will be available for cleaner, punchier bass.
A suspected problem of poor bass per-
formance is often caused by a weak AC
supply to the ampliers.
Never remove the ground
pin on the power cord
of the SWA2801z or any
other component. This is
very dangerous.

THERMAL

CONSIDERATIONS

The SWA2801z has a powerful amplier
built-in. As ampliers produce heat, it is
important to dissipate the heat as quickly as
possible. This results in increased reliability
and longevity for the amplier.
The amplier module is mounted on
a large heatsink, which is cooled by con-
vection where cool air is drawn through its
ns, carrying the heat away. In order for
this convection cooling to work efciently,
it is important to provide adequate airspace
behind the loudspeaker. When you position
the SWA2801z, we recommend leaving at
least six inches of air space behind it.
In the unlikely event of the amplier
overheating, a built-in thermal switch will
activate, which mutes the signal. When the
amplier has cooled down to a safe oper-
ating temperature, the thermal switch resets
itself, and the SWA2801z resumes normal
operation.
If the thermal switch activates frequently,
try turning down the level control a notch
or two on the mixing console (or other
signal source) or on the subwoofer itself to
avoid overheating the ampliers.
If the temperature in the room is too
high, it could cause the amplier to over-
heat. In this case, you should try aiming
a fan at the rear panel to move more air
across the heatsink panel.

SERVICE INFORMATION

Warranty Service

Details concerning warranty service are
spelled out on page 11 of this manual.
If you think your subwoofer has a
problem, please do everything you can
to conrm it before calling for service,
including reading through the following
Troubleshooting section. Doing so might
save you from being deprived of your Mack-
ie loudspeaker.
Of all Mackie products returned for
service (which is hardly any at all), many
are coded CND Could Not Dupli-
cate which usually means the problem lay
somewhere else in the system. The follow-
ing troubleshooting tips may sound obvious,
but here are some things you can check:

Troubleshooting

No power

Our favorite question: Is it plugged in?
Make sure the AC outlet is live (check
with a tester or lamp).
Our next favorite question: Is the
POWER
switch on? If not, try turning it on.
Is the
POWER
LED on the rear panel
glowing green? If not, make sure the AC
outlet is live. If so, refer to No sound
next.
The internal AC line fuse may be blown.
This is not a user serviceable part. If you
suspect the AC line fuse is blown, please
see the Repair section on page 9.