Removal/Installation Of Amplifier - Infinity MODULUS Service Manual

Modulus
REMOVAL/INSTALLATION OF MODULUS SUBWOOFER AMPLIFIER
I REMOVAL
1. Lay cloth or other protection under cabinet, lay unit down so that you are viewing the base (where the switch &
fuse are). Amplifier/heatsink should be at the top left corner at this point.
2. Unplug all external cables from unit (except on early models when the AC power cord is attached to the base).
3. Remove all phillips screws around the perimeter of the base plate (12). Do not remove center screws.
4. Base should now be removed from cavity. Because there is no protrusion to grab on to and there is a gasket
around the edges, screw one of the "feet" back into the T-nut on one of the corners (or a similar bolt) so you
have something to tug on. When the base is removed completely you will see 2 cables on the base attached to
the amplifier. These are "molex" connectors, and by reaching up to the point(s) where they are attached to the
amplifier and squeezing the connector they can be removed. The tab/catch on each connector faces
away from you (towards the top of the cabinet). At this point you may have to remove some or all of the
dacron filler in the cabinet. After removal, set the base off to the side.
Note: On some very early versions the smaller cable is so short the base cannot be removed enough to get
your hand inside the unit to unclip its molex connector. In this case the woofer must be removed first to
work through the opening.
5. Cut the two LED wires at about the midway point. Do not try to remove the LED from the cabinet.
6. The woofer must be removed from the cabinet to access both sets of soldered terminals (or clips on some
versions): (8) allen screws. Cut, unsolder or unclip both the (red and red w/stripe) main cables and the
accelerometer cable (grey, 3 wire) from their attached points. Note both the polarity of the main cables and the
three leads from the accelerometer. (More detail on this during re-assembly.)
7. Remove (4) phillips screws holding the amplifier in place. Two are close (near the base), two are deep in the
cavity (at the top of the box). One screw is not visible at all but its position can be determined from the screws
you've already removed.
8. With all screws out, grab the heatsink and turn it clockwise (when you are facing the base). It should break free
of the sealant and move about an inch in its slot. Now carefully pull the amplifier towards the base and
completely free of the slot.
II INSTALLATION
Is basically a backwards sequence from the above steps. Here are some additional notes:
On # 6:The polarity of both the main woofer cables and the accelerometer cable is very important . On the main
cable, the solid red wire should be soldered (or clipped) to the woofer terminal with the red mark. On
the 3-wire accelerometer cable where the small circuit board is present on the woofer, the locations are
as follows:
Note: On earlier versions of the control woofer no PC board is present on the woofer, the attachment
point is simply a 3 point barrier strip. On this version:
On # 5:The two LED wires should be connected by stripping, soldering and protected by heat shrink tubing or electrical
tape. Or small "wire nuts" can be used. Observe polarity (color).
On # 4:When re-filling the cabinet with dacron, try not to stuff the dacron too aggressively in the area of the woofer
cone. It could impede its movement. When attaching the molex connectors back on the amplifier, you
may need a flashlight to see the smaller molex connector (its position is in the center of the amp).
Another technique is to install the woofer last and work through the woofer hole. The squarish molex
connectors will only attach one way: The tab/catch on each connector must face away from you
(towards the top of the cabinet).
On #8: There is a black, non-hardening sealant on both ends of the amplifier assembly. Examine and "spread" the
sealant evenly on both of the end plates before actually re-mounting the amp assembly. A lack of
sealant could result in an air leak from the amplifier when music is played, adversely affecting the
subwoofer's performance.
(036-4393)
Red or white lead: "J4" on the circuit board
Bare wire: "J5" on the circuit board
Black lead: "J6" on the circuit board
Red or white lead: The red mark on the barrier strip
Bare wire: The middle point
Black lead: Opposite from the red mark
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