How to Bridge Speaker Wire
When configuring your amplifier and subwoofer setup in the car, one popular option is to bridge the output of an stereo amplifier and send the output to a single subwoofer. Bridging the amplifier increases the power output available. It's an excellent way to get the maximum power for your system from the amplifier. There's no special electronic skills or knowledge required when bridging. It's simply a matter of how the speaker wires that are connected to the subwoofer are hooked up to the amplifier.
Things You'll Need
- Wire strippers
Grasp the end of the speaker wire connected to the subwoofer and bring it to the end of the amplifier with the speaker output terminals. The terminals are typically marked "SPKR." Each terminal will consist of two screw terminals, one marked "+" and the other "-" One pair of terminals will be marked "R" for right, and the other "L" for left.
Loosen the screws on the right "+" terminal and the left "-" terminal with a screwdriver.
Identify which lead of your speaker wire is connected to the "+" terminal on the subwoofer and which is connected to the "-" terminal on the subwoofer by inspecting the connection. The leads of the speaker wire are usually color-coded or otherwise differentiated.
Remove a half-inch of insulation from the ends of the speaker wire leads at the amplifier end of the wire with a set of wire strippers.
Slide the bare end of the lead connected to the "+" terminal of the subwoofer into the right "+" terminal. Tighten the screw to hold the wire in place. Slide the bare end of the lead connected to the "-" terminal of the subwoofer into the left "-" terminal. Tighten the screw to hold the wire in place.
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