JBL SUB350
Service Manual

SUB350 SUB350 DISASSEMBLY PROCEDURE

Unplug all external cables; lay the subwoofer on a padded surface so that plastic cabinet base is facing upwards. 2) Remove the (4) oblong rubber feet from cabinet base, exposing the (4) recessed screws holding the base on. 3) Remove the (4) screws; remove the cabinet base. 4) Remove the (8) woofer mounting screws and remove the woofer; unplug the main speaker wires from the terminals. 5) Working in the woofer opening, disconnect molex connector CN601 at the bottom of the Main board mounted on the inside of the cabinet (2 large gauge red wires coming from power transformer) 6) Cut the plastic cable ties holding the large group of bundled wires together. 7) Identify and unplug the (6) molex connectors on the Main PCB mounted on the inside of the cabinet that must be removed to be able to partially extract the heatsink and Amplifier PCB�s. Use the map on the following page to identify. Observe the wire colors on each connector, and record on a piece of paper, or on this manual page each connector and it�s corresponding wire color. This is important to avoid mixing up the connectors upon reassembly. 8) Remove the (10) ¾� machine screws holding the main heatsink in place; remove only the screws on the outer perimeter 9) Pull the heatsink (with power supply and main amplifiers) out of the cabinet; you will not be able to fully separate this assembly from the cabinet because of several attached wires. 10) Normally the input/output plate (with power cord & switch) will not have to be removed; however, if necessary for the repair: a) Remove the (8) ¾� machine screws holding the input/output plate to the cabinet. b) Identify the (3) additional molex connectors from the Main board mounted on the inside of the cabinet that must be removed to be able to partially extract the input/output plate. c) If the controls need to be exposed for the repair, all adhesive must be removed from the connecting wires exiting from the rear of the plastic cover; then they can be worked free of the rubber grommets. Upon reassembly, a suitable adhesive must be reapplied to all wires such as hot-melt or silicon sealer. REASSEMBLY Use a backwards sequence from the above steps; some additional notes include: 1) 2) 3) 4) 5) Replace heatsink (and input/output plate if removed). Make sure all molex connectors are attached and plugged in their original locations. Refer to the map on the following page to assure of the correct locations. Replace plastic cable ties as necessary. Replace the woofer. Observe polarity when re-attaching wires; red wire to �+� symbol on the white woofer terminal. Re-fit plastic base to cabinet, reattach with screws, re-fit rubber plugs.

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