So you’ve got your speakers ready. You position them in perfect places in your room to achieve that robust home theater sound. You are all ready to plug them in when you discover; your speaker’s wire does not go as far as you need it to.
The most effective method is to strip the wire and use a wire cap. But before doing so you must consider the wire gauge and speaker impedance. In particular, your connection type and your wire gauge will determine which method you should proceed with.
Ideally, you would want to use a single length of wire, convenience and cost may overtake the minor loss in sound quality from using extended wires. Though, some claim that the “drop” in sound quality is merely a myth. This guide will take you through everything you need to know to extend your wire.
The first thing we need to be concerned with when it comes to speaker wire is the wire gauge. The gauge of a wire refers to its thickness. Gauge is expressed as a number where a higher gauge actually equals a thinner wire.
The thicker the wire, the more impedance or resistance the wire will have. This is good if you are running the wire over longer distances, however, you could lose power to your speaker due to this.
Thus, in general, you want to use the highest gauge wire you can get for the distance you intend to run your speaker wire over.
Although lower gauge wire can theoretically be extended over long distances, it’s recommended that you don’t run any speaker wire longer than 50 feet. If you need to run a wire further than this, it is highly recommended that you use wiring that is 12 gauge or less.
In general, you will want paired speakers to use the same length of wire to balance the impedance load between the speakers.
If you need to use different lengths of wire for paired speakers, you may need to use different gauges of wire, but calculating this is complicated and best left to a professional.
How Far Can I Extend My Speaker Wire?
One reason to use the same gauge of wire is that it makes it possible to easily calculate how long you can extend your speaker wire. Speaker wire, like any conductor, has a certain degree of resistance.
Resistance in lengths of wire results in loss of energy as heat. The longer the length of wire a current has to travel equals the more energy that will be lost as heat.
Because of this, as you use longer wire, you lose power to your speakers. The recommended maximum depends on two variables: wire gauge and speaker impedance.
Impedance is a measurement of the amount of resistance in the coil of a speaker. This is usually indicated on the back of the speaker.
Speaker impedance is measured in ohms, represented by the Greek letter omega, Ω. Speakers usually come in one of four impedance levels: 2Ω, 4Ω, 6Ω, or 8Ω. The higher the impedance, the longer you can extend your wire.
The wire is measured in numerical gauges; the higher the gauge, the thinner the wire and the greater the resistance. Because of this, the higher the gauge the shorter the distance you can extend your wire.
At 2Ω, 22-gauge wire can be extended about three feet without signal loss; 20-gauge wire can be extended about five feet; 18-gauge wire can be extended seven feet; 16-gauge wire can be extended 11 feet; 14-gauge wire can be extended 13 feet; 12-gauge wire can be extended 29 feet, and 10-gauge wire can be extended 49 feet.
At 4Ω, 22-gauge wire can be extended about five feet without signal loss; 20-gauge wire can be extended about nine feet; 18-gauge wire can be extended 15 feet; 16-gauge wire can be extended 23 feet; 14-gauge wire can be extended 39 feet; 12-gauge wire can be extended 59 feet, and 10-gauge wire can be extended 98 feet.
At 6Ω, 22-gauge wire can be extended about eight feet without signal loss; 20-gauge wire can be extended about 14 feet; 18-gauge wire can be extended 23 feet; 16-gauge wire can be extended 35 feet; 14-gauge wire can be extended 59 feet; 12-gauge wire can be extended 89 feet, and 10-gauge wire can be extended 148 feet.
At 8Ω, 22-gauge wire can be extended about 11 feet without signal loss; 20-gauge wire can be extended about 19 feet; 18-gauge wire can be extended 31 feet; 16-gauge wire can be extended 48 feet; 14-gauge wire can be extended 79 feet; 12-gauge wire can be extended 118 feet, and 10-gauge wire can be extended 195 feet.
The above maximums are the maximums to ensure that your cable resistance is less than 5% of your speaker’s impedance.
Remember, although these are estimated maximums, it’s not recommended for you to extend your speaker wire more than 50 feet.
Can I Mix Wire Gauges?
Some audio nerds will tell you that mixing wire gauges is a big no-no. There are some reasons for this. For starters, mixing wire gauges will make it extremely difficult to calculate impedance over the length of your combined wires.
This is bad if you need to be accurate about the impedance load difference between your amplifier and your speakers.
Unless you’re looking for a perfectly balanced sound system regarding every electrical spec, splicing wires of different gauges won’t be that detrimental to your sound and, most importantly, shouldn’t damage your audio equipment.
Thus, unless you are trying to get your sound system to very particular electronic specs, you shouldn’t need to worry about mixing wire gauges. That said, it should be avoided where possible.
There are a number of instances where splicing a wire may be necessary to extend a speaker wire. Some examples are if you can only find spools of wire shorter than the length that you need or if the lengths of wire you have are shorter than the length that you need.
In either case, you will need to splice the wire–a process that involves stripping and joining the wires. There are a number of ways to accomplish this and they all achieve the same result.
Regardless of the method you use to splice a wire, you will need to strip the wire of some of its rubber tubing to expose the bare wire. This can be accomplished most easily with a wire stripper.
A wire stripper is a tool that has inserts for wires of various gauges. Simply insert the wire into the appropriate gauge slot, clamp the wire stripper, and pull and the rubber tubing will be pulled off the wire.
If you don’t have a wire stripper, a wire cutter may also be used to strip a wire, though this method requires a more delicate touch. Put the wire cutter at the length you want to strip.
Lightly clamp the wire with the wire cutter, cutting only through the tubing but not the wire underneath. Twist the wire cutters around the wire and pull the tubing off, leaving the bare wire underneath.
Using a Wire Cap
One of the easiest ways of splicing a wire is using a twist-on wire cap. Simply put the two wires you would like to splice side-by-side facing the same direction. Affix the cap to the ends of the wires and twist clockwise to tighten the wires together.
After connecting the wires, secure the wires to the cap with electrical tape. To disconnect the wires, simply twist the cap counterclockwise.
Using a Butt Splice
A butt splice is a connector that allows the indirect connection of two wires through a conduit. For a butt splice, you will need a wire crimper. Insert one wire into the butt splice and crimp with the wire crimper.
Insert the butt splice and wire through a length of heat shrink tubing and then connect the other wire to the other end of the butt splice as above.
After crimping the second wire, pull the heat shrink tubing over the butt splice and heat with a hairdryer so that the tubing covers the butt splice and a little of each wire.
Using a Soldering Iron
A soldering iron uses a low-melt alloy called solder, usually based on lead or tin, to fuse wires together. This provides the most direct and secure connection for wire splicing.
To splice a wire with a soldering iron, start by feeding one end of the wire through heat shrink tubing. Twist the two bare ends of the wire together and touch them to the heated soldering iron.
Apply solder so that it drips onto the twisted connection point between the wires. After the wires are connected, pull the heat shrink tubing over the connection point and heat with a hairdryer.
You Can Do It
With a little time and maybe a little money, there’s no reason why you can’t put your speakers exactly where you want them.
Whether you’re trying to get more distance between your speakers or you’re snaking your speaker wire around the room to keep them hidden, even a novice A/V tech can extend speaker wire to the length that’s required.