How To Extend Speaker Wire: Step By Step Instructions For Splicing It & More

In this detailed how-to guide, I’ll show you how to extend speaker wire for longer length with great results. It’s not very hard once you know how to connect & splice wire correctly.

There’s a basic diagram included right at the top. However, for best results be sure to check out my detailed steps & photos below (and to find out which way is best for you).

Quick diagram: how to splice & extend speaker wire

How to splice speaker wire diagram

First things first: here’s a simple diagram covering the basics for stripping & connecting speaker wire using one of the 2 most reliable ways.

You’ll only need a few tools to do it. Between the two ways, using solder is extremely reliable but more hassle & takes more time. Crimp connectors, however, give great results in only minutes and this approach is what I use most of the time for my home or car installation jobs.

While my diagram may be helpful, I’d like to help you understand the pros and cons of each so I can help save you time, hassle, and maybe even a bit of money, too.

Read on to learn more about these plus other options you have.

How to splice wire with crimp connectors

How to splice and extend speaker wire with crimp connectors section image

Using crimp connectors is one of my favorite ways to splice & extend speaker or power wire as a professional installer. It’s fairly fast and gives professional results with very little hassle or work.

This is my top recommended way to extend speaker wire for nearly anyone.

Here are a few reasons why I recommend it:

  • When done properly, it’s very reliable and the wire won’t come apart
  • Easy to do – only takes a few minutes
  • Not affected by temperature changes & time
  • Crimp tools & connectors are widely available and are affordable

There are only a few steps involved: cutting the wire (if needed), stripping the wire, and preparing the wire & crimping the connectors.

1. How to cut speaker wire

Image showing examples of how to cut wire

Examples of some of the best ways to cut speaker wire using tools or a pair of utility scissors. Cutting wire is easy with the correct tools. Many tools like wire strippers or crimpers also have a cutting feature built-in.

Cutting speaker wire (or power wire) normally isn’t hard but you definitely need the right tool. The reason why is that common tools like regular scissors can’t cut wire properly and can even become damaged.

Some great tools are very affordable that will cut wire very well and make extending or repairing speaker wire much easier:

  • Cutting pliers
  • Automatic wire strippers with a cutter section
  • Needle nose pliers with cutting section
  • Crimper/stripper tool with cutting feature
  • Utility scissors – works ok for smaller gauges, not larger

Of the 5 listed here, I recommend and use wire cutting pliers as they’re capable of cutting a wide range of wire sizes. For typical speaker wire like 18 gauge, the wire cutting feature on many other tools works fine.

Ultimately, though, it’s a lot more convenient to have an “all-in-one” tool like a crimp tool if you’re only doing light work occasionally.

Wire cutting tips

To cut wire, just insert the wire and slightly close the tool until the wire is securely held in place & can’t move. Then squeeze very firmly. The wire should “snap” lightly and will be cut.

While you can get by with utility scissors (don’t use standard scissors used for paper or fabrics!) you’ll have to insert the wire right at the inside of the blades and cut very carefully.

Scissors aren’t a good choice and the wire can even get jammed inside.

2. How to strip speaker wire

How to strip wire example

To strip speaker wire you can use a number of tools. I recommend standard wire a standard low-priced wire stripper/crimper (shown above) or similar.

Stripping speaker wire can be a little bit tricky, but it’s a skill you’ll pick up quickly after a few tries. The main trick is to pinch only the wire’s insulation and not the wire strands themselves.

If you catch the wire inside by squeezing a stripper too hard you’ll likely break off of the wire strands.

To strip wire:

  1. Insert the wire in the stripper and close it carefully on the insulation. Use enough force to hold the wire in place and slightly pinch the insulation, but not enough to put force on the wire inside.
  2. Hold the tool & pressure in place firmly so it cannot move.
  3. Pull the wire. The insulation could break off and the exposed wire should remain.
What to know before stripping speaker wire the first time

Certain types of wire (especially smaller gauges like 20AWG, 24AWG, etc can be harder to strip without breaking. For your first few times, practice on some surplus wire that won’t hurt your speaker wire length needs.

Once the wire is stripped you’re ready to connect it & splice using crimp connectors.

Image showing ruler next to 1/2 inch stripped wire

I recommend stripping enough wire to leave about 3/8″ to 1/2″ wire exposed.  For soldering, you’ll need a minimum of 1/2″ to be able to twist the wire together.

For crimp connectors, 3/8″ or more should be fine.

3. How to use crimp connectors with speaker wire

How to use crimp connectors with wire instruction steps image

Once you’ve prepared your speaker wire by stripping it, it’s time to use a crimp connector on each wire and a tool to crimp them for a reliable connection.

Using crimp connectors with speaker wire isn’t very hard – I promise! You’ll get the hang of it after a few tries.

How to crimp speaker wire properly:

  1. Strip the wire leaving 3/8″ to 1/2″ bare wire exposed.
  2. Tightly twist the wire so it can be pushed into the connector properly.
  3. Insert the wire into one end firmly, pushing it into the metal contact inside. Be sure to insert it fully.
  4. Place the connector into the crimp tool in the appropriate position in the tool, near the end of the connector.
  5. Crimp very hard with the tool to make press the connector down hard, holding the wire inside permanently.
  6. Repeat the same for the other side & speaker wire.

Tip: For best results, once you’re done pull gently on the wire while holding the connector. The wire shouldn’t come out. If it does, you’ve crimped it poorly and will need to do it over again.

What should it look like when you correctly extend speaker wire?

Closeup example of properly crimped speaker wire

Crimp connectors, also sometimes called butt connectors, are sold in standard colors for the range of wire gauge sizes they can be used with. Although red is listed as fitting 18 AWG wire, I’ve been using blue butt connectors with 18 AWG wire for years without problems.

Wire crimp connector examples with wire gauges labeled

Examples of “butt” (crimp) connectors are shown here. They’re sold based on the wire gauge they can be used with.

I recommend trying that as since the internal opening is a bit bigger you can be sure they’ll fit with various types of speaker wire near that size. That’s because speaker wire manufacturers sometimes have different internal wire conductor sizes.

Splicing speaker wire by soldering

Image showing steps for how to solder speaker wire

This is hands-down the most reliable way to extend & splice speaker wire. When done properly soldered wire is extremely strong.

How to solder speaker wire

To begin, follow the wire cutting & stripping steps from the first section (using crimp connectors).

Follow these steps:

  1. Cut & strip the speaker wire (at least 1/2″ length of bare wire is needed).
  2. Hold up both ends to form an “X” shape with the wire facing opposite directions.
  3. Hold both ends and tightly twist each end around the other until they’re completely wrapped over each other.
  4. After the soldering iron is hot, apply heat to the wire with the tip. Once heated (after a few seconds usually), apply solder enough it has flowed fully through the wire.
  5. Rotate the wire to the other side and apply the solder until all of the wire is fully saturated with solder.
  6. Allow the wire to cool for a few moments.
  7. Tear 2 short pieces of electrical tape. Starting at the insulation and at an angle, tightly wrap the tape until it is fully covered.

It’s important to fully cover the wire once you’re done. That’s to prevent the wire from touching each other and cause a short circuit that can permanently damage the output components in an amplifier or stereo.

How long does soldering speaker wire properly take?

All in all, you’ll need about 10-15 minutes to do this work with a soldering iron vs about 1-3 minutes with crimp connectors.

Example of soldering iron and accessories needed to solder wire

Budgeting for soldering speaker wire

A soldering iron can be bought for about $7-$10. You’ll also need some electrical wire and solder, too. For best results, I recommend at least a 25W soldering iron to get the wire hot enough for the solder to flow well.

Using twist connectors (wire nuts)

Example showing how to use wire nuts twist connectors

Wire nuts, also called wire twist connectors, are typically used for wiring installation in homes & buildings. They’re another option although I don’t recommend them as they’re a bit less reliable than crimp connectors or solder.

Wire nuts work by using a threaded metal insert to screw down onto the wire, holding it together as it goes.

They’re pretty fast, but unfortunately, on occasion, I’ve seen them come loose from wire so I don’t advise using them. Instead, I’d highly recommend crimp connectors.

Why you shouldn’t do it the “just twist and tape” way

Example of speaker wire extended by twisting and wrapping with tape

You may be tempted to use the “just twist and tape” method, but I strongly encourage not to do so.

Why? Because it’s very unreliable and can be a mess to fix later. If the wire comes apart, as often happens, you can potentially damage your stereo or amplifier due to a short circuit.

It’s not worth the risk!

Simply twisting the speaker wire and then wrapping it with tape isn’t enough. In my experience as an installer, over time the 2 speaker wires will begin to separate since they’re not held together. To make matters worse, over time heat can affect electrical tape and it can begin to come off of the wire.

It also leaves behind an adhesive residue if it has been subjected to a lot of heat as often happens in car audio installations.

Which speaker wire is positive? Which is negative?

Which speaker wire is positive diagram with examples

The most common kinds of positive wire markings are shown here as examples. 99% of the time, figuring out which wire is positive is really easy once you know what to look for.

The good news is that once you know what to look for, 99% of the time it’s very easy to tell which speaker wire is positive and which is negative.

How do I check if a speaker wire is positive or negative?

Here’s a list of the most common ways to tell which is the positive wire:

  1. A printed line or series of dashes/lines is on the positive wire
  2. One wire’s insulation is red or a different color than the negative wire (most often red is used)
  3. One wire has a copper color and one has a silver finish
  4. The positive wire may have small positive (“+”) symbols and/or wire gauge info printed on it
  5. An imprint or molded stripe is made in the positive wire’s insulation

Of the 5 kinds, imprints can occasionally be a little bit harder to notice so sometimes you need to look very closely under good lighting. Also, positive wires that use a “+” print can be a little hard to read sometimes, too.

Which is positive: copper or silver?

Closeup example of positive & silver speaker wire

These are less common, but of speaker & power wires that have a copper and a silver color, you can pick one of the two to be positive. However, as a rule the copper wire is treated as the positive.

The “silver” wire isn’t really silver – it’s copper wire that’s been lightly coated (“tinned”) in most cases.

Once you know which is the positive wire then the other is the negative wire.

Music uses alternating current (AC) signals and doesn’t flow in only one direction. We use one wire as the positive one when connecting speakers to be consistent when connecting them so as to wire them all the same way for the best results.


About the author

Marty is an experienced electrical, electronics, and embedded firmware design engineer passionate about audio and DIY. He worked professionally as an MECP-certified mobile installer for years before moving into the engineering field. Read more »

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