How to Bridge Four Audio Subwoofer Speakers

When setting up an audio system with subwoofers, you are going to want to get the maximum power out of your amplifier. All subwoofers are marked with a maximum RMS wattage. You are not going to want to exceed the power of this number when powering from your amp. However, you do not want to underpower your subs, either, as you will not get the maximum bass that you are looking to achieve. Bridging the amplifier is the solution to this. It is relatively easy to do with four subs.

Things You'll Need

• Thick-gauged speaker wire
• 4 subwoofers
• Amplifier

Instructions

Bridging the Amp

1. 

   Cut the speaker wire to the desired lengths and connect to subwoofers. On each subwoofer box there will be a positive (+) and negative (-) connector. Simply take one end of the cable and connect one of the wires into the positive and one to the negative. Repeat this step for all four subwoofers. The other end should not be connected to anything yet.

2. 

   Bind the wires. This is where using the quality speaker wire is going to come in handy. Take the ends of all the speaker wires that you have not yet connected to anything and bind all the positives (+) together, and all the negatives (-) together. You should now have four positive wire ends that are twisted together into one, and four negatives.

3. 

   Connect to the amplifier. If you are running four subs, then you will probably want a 1500+ watt amplifier. Take the bundle of the four negative (-) twisted wires and connect them to the negative sub-port on the amplifier. Also, take the four bundled positive (+) twisted wires and connect them to the positive sub-port on the amp.

4. 

   Test it out. You have now successfully bridged your amplifier. What you have gained from doing this is the advantage of combining all of your amplifiers power into one channel and distributing it on all four subwoofers. This will give you maximum bang for your buck. Put in a CD with plenty of bass, make sure that your amp is turned down and make adjustments from there.

Tips & Warnings

• When bridging four subwoofers you are more then likely going to use a lot of speaker wire. Buy the speaker wire that is made with a different color wire for positive and negative. It will be less confusing this way, and it will also will help with any future adjustments.

Resources

• Crutchfield