Honda CR-Z (EX) Polk Speaker and Subwoofer Upgrade

Start at the front doors, where the component woofers will mount. Follow a CR-Z-specific door-card removal reference for the exact fastener and clip locations. Work slowly and lift the trim gently. Pay particular attention to the narrow plastic covers running along the base of each window: their retaining tabs are fragile and snap with very little force, and replacement pieces are expensive. If any adhesive residue smears onto your skin or the panel, wipe it away with isopropyl alcohol; soap and water will not touch it.

With the inner door metal exposed, apply sound-deadening material before mounting any speakers. A quality butyl product such as DynaMat cuts road noise, gives the doors a solid closing thud instead of a hollow ring, and creates a better acoustic baffle for the new speakers. Cheaper asphalt-based alternatives exist, but they have been reported to give off an odor and to peel from vertical surfaces in summer heat, so favor a durable product if you do not want to reopen the doors later. Cover the door cavity, then add material around each speaker opening.

Each factory door speaker is retained by a single 8 mm bolt at its top edge. Remove that bolt, push the speaker upward about an inch to free it from its slot, then pull it outward; the factory units are glued and may need firm force. Deaden around the now-open hole. Fit the Polk spacer rings, which are not optional: they move the larger aftermarket magnet clear of the window mechanism and bring the cone closer to the door-card grille. Trim any surplus tabs from the spacers, then drill four pilot holes with a 1/8-inch bit so the included screws thread directly into sheet metal without backing nuts.

Cut off the factory speaker connector, then slide the supplied rubber gasket onto the wires first so it will seat between the speaker and spacer; it is easy to overlook and awkward to add after soldering. Solder the leads to the woofer terminals with correct polarity. Front left (driver's) door: Light Blue is positive, Gray is negative. Front right (passenger's) door: Blue is positive, Red is negative. When mounting, logo orientation does not matter behind the grille, but rotating the speaker so its solder tabs point downward takes advantage of the extra room in the factory cutout. Repeat on the opposite door.

Free each dash tweeter panel by running a putty knife around its seam; the panels release with light effort. They scratch easily and reveal white marks, so handle them carefully, and touch up any scuffs with a black permanent marker. Pry out the three tabs on the factory tweeter holder and remove it; the holder is discarded, so it does not matter if it breaks. With a Dremel, rout a 2-inch opening where the factory tweeter grille sits, removing all the raised holder material until only the flat panel face remains. Install each flush-mount cup's metal cross-retaining clips at its rear before seating the tweeter, then solder the leads. Left tweeter: Gray is positive, Light Blue is negative. Right tweeter: Red is positive, Blue is negative. The tweeter polarity is the reverse of the door speakers; an early wiring diagram in the thread showed the tweeters swapped, which fergsonfire corrected.

Do not install the crossovers packaged with the Polk components. On the EX, the factory 340-watt amplifier already applies a frequency roll-off to the front channels; sweep testing from 200 Hz to 20 kHz showed no audible difference with the crossovers in place or removed. The tweeters are also not wired in series with the woofers, which would make retrofitting the crossovers impractical. Important: this applies only to the EX. The non-EX system does not have that built-in roll-off, so the Polk manual's caution against driving tweeters without a crossover does apply there; confirm which system your car has before omitting them.

The rear speakers install faster than the fronts but sit tight. Pry off each rear grille with a flathead screwdriver wrapped in masking tape. Even with the spacers, the coaxial magnet contacts the body panel and keeps the frame from sitting flush by a millimeter or two. The simplest fix is to triple-layer the deadening material on one side of the mount, shimming the speaker outward. Alternatively, use the shallow-mount Polk db651s, which clears the panel without the magnet touching. Wire the rears with correct polarity. Left rear: Gray is positive, Brown is negative. Right rear: Blue is positive, Orange is negative.

Finish with the factory sub, which gains low-end response from polyester fill that makes the sealed box behave as though it were larger. In the rear cargo area, pull the plastic guard from the center of the lower hatch trim, lift out the trunk mat, and remove the spare tire and its foam surrounds. Pry back the left side of the hatch trim to reach the sub box, remove its four bolts, disconnect the connector, and lift the box out. Unscrew the grille and the subwoofer, loosely pack the enclosure with the stuffing from an extra-firm standard pillow, then reassemble in reverse order.