How to Hook Up Speakers to an Amp

By James Dryden

You've just purchased 440-watt speakers capable of a gust-busting 91 decibels, backed by a 440-watt four-channel amplifier. The only problem here is that you're a bit lacking in the wiring department and want to make sure you've correctly put together these monster noise machines---all for the sake of blowing your neighbors out of their lounge chairs. No worries. Hooking up speakers to an amp is simple.

Things You'll Need

  • Wire cutters
  • 16-gauge, 2-conductor speaker wire
  • Pin connectors

Wire 101

Step 1

Measure the distance from the amplifier to the speakers. If the speakers are close to the amplifier, say within 80 feet, 16-gauge wire will do fine. If the speakers are further away, you need thicker wire---12 to 14 gauge---for better conductivity.

Step 2

Note the travel path of the speaker wire when measuring the distance from the amp to the speakers, say if you are running the wires down to the floor then back up to the speakers.

Step 3

Use a piece of string as a substitute for positioning the wire from amp to speakers, then measure the length of that string as an indicator of how much speaker wire you will need.

Step 4

Once you've got the correct length of wire, gently cut the wire straight across with your wire cutters.

Strip the Wires

Step 1

Note that the wire is divided into two separate strands; each of the strands is called a conductor. Within those conductors is a copper, silver or gold bundle of wires. The strands are bundled in heat-shrunk plastic tubing (insulation) and are often protected by other materials, depending on the quality of the speaker wire.

Step 2

Examine the markings on the insulation. Notice that one strand's insulation has either a + or a - symbol running the full length of the wire. Sometimes one of the strands will have a thin white line running the full length---or for easy identification, the insulation just might be two separate colors: red and black. These colors and symbols are for the polarity, the negative (-) and positive (+).

Step 3

Use your wire cutters to split the wires down the middle by cutting along the thin barrier of insulation that separates the strands. Cut down about 3 inches to separate the two strands.

Step 4

Gently cut into the insulation of the positive polarity strand about 3/8s of an inch from the tip around the bare wires using your wire cutters. Be careful not to cut into the wires. The insulation should slide out around the wires, leaving them exposed. Repeat this process with the negative polarity strand. Then repeat with the other speaker wire.

Make the Connection

Step 1

Look at the back of your amplifier for the speaker wire terminals, which are usually small red and black plastic squares with holes in them. These squares are often held in place with screws and a spring mechanism.

Step 2

Twist the bare wires into a single, more manageable wire.

Step 3

Push back on the spring connector to open the little hole and insert the exposed wire into the hole, all the way up to where the insulation begins, and release the spring connector. Remember to insert the positive polarity wire into the red spring connector. Insert the negative polarity wire into the black spring connector.

Step 4

Gently tug on the speaker wires to make sure the connections are snug.

Step 5

Repeat the process to hook the wires up to the back of your amplifier.

Step 6

Put your favorite chair in front of your new-found power blasters, crank them up to 11 and blow yourself away.

Tips & Warnings

  • Remember: Red = positive (+); black = negative (-)Choosing speaker wire can be complex or simple: Follow the recommendations that come in the manual for your sound system.Resistance is also something to consider when choosing speaker wire: The lower the resistance, the more power can travel through the wire. Resistance will begin to have an audible effect on the listener when resistance exceeds 5 percent of the speaker's impedance. It is perfectly acceptable to use heavier-gauge wire for high-end audio equipment, even if your amplifier is 6 feet away from the speakers; be aware, though, that heavier wire does not have the same flexibility as thinner wire.If you wish, you can twist the exposed wires into a pin connector, which can then be inserted into the hole of the spring clip. This method will also give you a more secure connection. Your speakers might also have binding posts, which make more secure connectors than spring clips. Binding posts are also red and black. If you are connecting to a binding post, you still need to follow the positive wire to red/negative wire to black rule. Here, however, you will first unscrew the binding post cap, insert the tip of the exposed wire into the binding post, then put back the cap, which will secure the wire in place.
  • Work safely: Disconnect the power from your equipment before you hook up your speakers.