2008 Chevy HHR Audio Buildup - Audio Buildup On A Budget

Moving to the MTX amps, both the 504X four-channel amp and the 300XD sub amp were test-fitted under both front seats. The amps had plenty of room and each seat was removed to gain easier access to mount and wire the amps.

The Streetwires positive and ground wires were run to each amp and then the speaker wires and head unit RCA cables connected.

At this point, the amps were secured to the floorboard and the seats reinstalled, along with the rubber floor mats. With the amps in place, there was no loss in foot room for the rear passengers.

Providing added flexibility, the MTX 300XD sub amp included a bass knob to give the sub extra juice. This knob was mounted under the dash on the driver side.

The battery is located on the passenger side in the rear cargo hold area, and once we found it, Sam wired the Streetwires 4-gauge wire to the battery and then secured the ground cable to the body.

Here you can see the middle level of the rear cargo area cover. It was removed to gain access to the spare tire.

The stud was then cut off and the sub box measurements taken. As you can see, there was plenty of room for a sub box to be built in the well.

We then opened up the MTX TS5510-22 subwoofer box and got to check out the square sub. This sub is rated at 225-450 watts RMS and needed 1 cubic foot of air space to achieve optimum sound reproduction. With a 5lb magnet, this sub meant business.