How to Splice Wires for Speakers and Home Theater Systems

Properly Place Speakers and Equipment

Before you start splicing, properly set up the speakers and equipment. Turn off the power to the home stereo receiver and disconnect the power cords. Unplug and examine all speaker wires, then set them aside for later use. Any that appear damaged or in poor condition should be thrown out.

Now you're free to move speakers to their new locations. Time permitting, this can be a great opportunity to consider how you might hide or disguise speaker wire in living areas. With the proper techniques, wires can be put safely and aesthetically out of sight.

Measure Distance and Cut

After the speakers have been placed, determine the length of wire required to connect each speaker to the stereo system. Use the measuring tape and tally the distances. It's better to overestimate slightly than underestimate, as slack is easy to manage, and splicing involves a bit of trimming anyway.

Write down the numbers along with the speaker location (for example, front left/right, center, or surround left/right) in a notepad. When finished, measure the speaker wire you set aside earlier and compare it to your notes. There's a chance that some of those wires will be the right length. Also, double-check that the wires are the proper gauge.

If you have wires that don't need splicing, label them with the assigned speaker and set them aside. Cross those speakers off your notes so that you know they've been accounted for.

Choose any remaining wire and assign it to a speaker with a label. Calculate the difference between the length of wire you have versus what the speaker needs. This is how much you'll cut from the spool of speaker wire. Give yourself an extra inch or so and make the cut using the wire strippers. Label the pairs of wires, set them aside, and cross the speaker off your notes. Repeat this process with any remaining speakers on the list.

Strip the Wire and Attach Crimp Connectors

Take one set of wires that you intend to splice and place the ends/terminals next to each other—negative to negative (-), positive to positive (+). You want the wires to be in-phase. If you're unsure, test the speaker wires with a battery. Using the wire cutters, strip off the exterior jacket/insulation so that all four ends have a quarter-inch of exposed copper wire. You can separate the individual wires (positive and negative terminals) by an inch, so you have room to work with them.

Take both negative ends of bare wire and insert them into opposite sides of a crimp connector. (Double-check that it matches the gauge.) Using the crimping section of the wire cutters (it should be marked so that you correctly match the gauge), firmly squeeze the connector so that the connector's metal tubing shuts close around one of the bare wires. Do this once more for the other bare wire.

Gently tug on the speaker wires to ensure that they hold fast. If you want to double-check the electrical connection, use a battery for a quick test. Repeat this process with the positive ends of the bare wire with another crimp connector.

Apply Heat to Shrink Connectors

After attaching the crimp connectors to the positive and negative wire ends, gently apply a heat source to shrink the connectors. A hot air gun or a blow dryer set to high heat is best (held a few inches away), but you can use a lighter if you’re extremely careful and hold the lighter at least an inch away.

Hold the wires with your offhand (a few inches below the crimp connections) as you apply the heat. Slowly rotate the wires/connectors so that you get around all sides. The crimp casings will shrink snug against the speaker wire, creating a protective and waterproof seal. Some electrical crimp connectors are designed with a bit of solder on the inside, which melts from the heat and fuses the wires for a stronger connection.

Continue stripping speaker wires and attaching/shrinking crimp connectors until all lengths have been spliced and extended.