Specifications

makes them highly resistant to water damage.This compound has an impor-

tant secondary purpose: the cones will not change mass due to moisture

absorption in humid weather, making the system’s sonic qualities exception-

ally stable when used in varying climactic conditions.

Occasionally, due to mechanical shock or abusive operation, a driver may

become dysfunctional. Drivers can fail completely, or they can fail in such a

way that they continue to reproduce sound but their output becomes

noticeably distorted. The latter is usually due to deformation of the voice

coil, resulting in the coil rubbing against the gap. In either case, driver replace-

ment is warranted.

To v erify if a driver has failed, remove the front grille and listen to the system

at a moderate level. By lightly touching each driver while playing program

material, you can readily tell if it is actively radiating or passively responding

to the other driver’s pressure.

Before attempting to replace any parts in the APL-10, -12, or -SB, be certain

to disconnect the power cable from the unit. Lethal voltages are present

inside the enclosure when the unit is connected to an AC mains supply!

The drivers in the APL-10, -12, and -SB can be changed in just a few minutes.

To gain access, first remove the front protective grille with a Phillips screw-

driver.After the grille is removed, the driver itself can be removed by simply

loosening the eight (8) Allen-drive fasteners that retain it, and lifting it out of

the enclosure. If possible, perform this task with the enclosure resting on its

rear surface. This will ease the process and minimize the force that would

otherwise be placed on the driver as the fasteners are loosed, if the enclo-

sure were upright.To remove the driver after the eight Allen-drive fasteners

have been taken out, reach through the nearest bass port with your hand and

push the driver upwards.The gasket sometimes sticks a bit, so do not hesi-

tate to use a little force to unseat the driver from the gasket.

Once the driver has been removed from the enclosure, disconnect the

speaker wires from the terminals. To replace the driver, simply reverse the

disassembly process, making sure to connect the speaker wires properly.The

black wire goes to the black terminal on the driver, and the red or white wire

goes to the red terminal on the driver.

NOTE: If the driver is connected backwards (out of phase), it will not func-

tion properly and could be damaged rapidly. In dual driver models (APL-10

and -12) it could also damage the other driver in the enclosure.

After the driver is connected, place it carefully over the opening and rotate

it to align its holes with the eight threaded inserts in the enclosure. Then,

install the fasteners, being careful to tighten them gradually in a cross-pattern

so as to equalize the force placed on the driver’s rim. Do not over-tighten

the fasteners or the driver’s rim may become warped! Two to three foot-

pounds of torque is sufficient.