Brown knew that this was Cajayon's everyday vehicle so he utilized the factory speaker locations. Up in the front doors, BMW provides customers a speaker setup with a six, four, and a tweeter. The four is located towards the rear of the door while the six and tweeter are located in the front. This application didn't make much sense, so Brown opted to use the 4" drivers for something else. In place of the other speakers, Cajayon chose Alpine's newest speaker line. A set of SPX-177A 6 1/2"components replaces the factory. Brown made it a point to run the upgraded speaker wires through the door boot to keep them out of sight. The factory tweeter mounts were utilized, but new templates were made to hold the 6 1/2" in the bottom of the door. A small sealed enclosure of about .33 cubic feet was fitted into the door.
Brown utilized the OEM 4" drivers as the speakers for the navigation system. In the rear, a pair of Alpine SPX-137A 5 1/4" components replaced the factory setup in the rear deck. This was a rather easy swap as Brown made a baffle board out of 1/4" particleboard to mount the speakers.
Unseen Work
It is in the trunk where signature Steve Brown is most evident; and it is underneath all of the finishing panels where a good portion of the work occurred. The subwoofer enclosure is nestled into the driver's side of the trunk. Brown constructed the enclosure using approximately 24 pieces of 1/2" MDF to best utilize every nook and cranny of space. Once the rear portion of the box was completed, he made a rectangular port, which exits right below the woofer. All the gaps were filled in with Mar-Glass (reinforced body filler) and fiberglass was applied to ensure the enclosure would not have any leaks other than through the port. Then a speaker ring was constructed, also out of MDF, to hold the woofer in place. Once finished, carpet was laid over the whole box to form a shape; it was stapled down, then fiberglass mat was applied. The total internal volume of the enclosure is 1.5 cubic feet. To keep the box in place, Brown used factory bolts to screw the box into the floor. Tightening the box down is achieved through the speaker cutout. An Alpine SWR-1240 12" subwoofer handles all of the low frequencies. "This enclosure is perfect for the woofer we used. The output from just the single twelve is quite impressive," states Cajayon.
Since the vehicle was not ordered with fold-down seats, Brown had to figure out how the low frequencies would travel into the cabin. Fortunately, when removing the rear seats, a cut-out for the ski hole somewhat already existed. It was closed off with sheet metal that was tack welded in four places. Brown simply punched out the sheet metal and, viola, an instant pass-through was created. When folding down the rear armrest, you can view the high-end crossovers for the SPX speakers.
When the subwoofer enclosure was finished, Brown moved to the opposite side, which Cajayon calls the "Mobile Multi-Media Center." Brown stacked an Alpine DVA-5205 Mobile DVD Player, an Alpine NVE-N851A DVD Navigation system, and an Alpine CHA-1214 CD changer above the battery. Notice the silver face on the DVA-5205. This particular model comes with a black face, but Cajayon wouldn't settle for that because he wanted all of the components to match in color. When asked where he obtained the face, Cajayon simply replies, "Working for the manufacturer has its merits." A rack was made of 1/2" MDF to hold each piece with an extension built towards the front of the vehicle to hold the brain of the IVA-C800. The same procedure of carpet and fiberglass was used to create the shape. Once dry, body filler was used, and Brown went as far as making sure the cover piece molded into the shape of each component.