How to Wire Two 4-Ohm Channel Amps to Two Subwoofers
- 1). Cut the speaker wire into four 2-foot sections. Since speaker wire is composed of two individual wires, strip 1/2 inch from each end of each of the wires.
- 2). Connect one of the subwoofers to the terminal cup in one of the subwoofer boxes. A subwoofer box holds the subwoofer, and the terminal cup provides a connection point between the amp and the subwoofer. Attach the speaker wire to the two terminals on the subwoofer and the two terminals on the terminal cup. Make sure that the polarities are matched. Once connected, fasten the subwoofer to the box using 1 1/2-inch screws.
- 3). Connect one of the amplifiers to the subwoofer box. Attach a length of wire from channel one of the amplifier to the terminal cup on the outside of the subwoofer box. Once again, make sure that the polarities match up.
- 4). Repeat Steps 2 and 3 for the other subwoofer, subwoofer box and amplifier. Adjust the settings on the amplifiers and on the main stereo unit according to manufacturer recommendations.
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