How-to guide

The Speaker Wiring Diagram And Connection Guide – The Basics You Need To Know

We all enjoy music and speakers make that possible – but it can be confusing if you’re unsure of how exactly to connect them.

In this post, you’ll find clear and detailed speaker wiring diagrams that will help (and print out if you like, too!).

I’ll go into detail about the right and wrong way to wire speakers and connect them properly to your stereo or amplifier. It’s actually pretty easy once you learn the basics.

Contents

Printable speaker wiring diagram

Click on the image to enlarge it or click here for the Adobe .pdf version you can download and print.

Image of illustrated speaker wiring diagram

Speaker basics and speaker wiring explained

1.  What is speaker impedance? (the “Ohms” rating)

Speakers, much like other electromechanical devices, all have an electrical resistance to the flow of electrical current, much like a standard resistor, a light bulb, or many common items you’re familiar with.

The difference is how they behave when music is present when they’re connected to a musical amplifier of some sort.

The resistance value comes from a long coil of wire inside each speaker called a voice coil. A voice coil is a coil of wire that, when placed inside a magnetic field, makes the speaker move and produce sound when driven by an amplifier.

Image of a speaker voice coil
Speakers contain a long wound loop of wire called a voice coil. Loops of wire have a property called inductance which affects a speaker’s resistance value depending on the frequency (sound range) being played.

As they have electrical properties that include inductance and capacitance, their “total resistance” can actually change with the music slightly. Because of this, there’s some additional complex math needed to figure out the total resistance. The word used to describe this is called impedance.

Speaker impedance is just a more sophisticated way of finding the total resistance, and by tradition is measured with units called “Ohms.”

The good news is that you don’t have to worry too much about the details – it doesn’t matter for basic speaker use, and long as you observe the basic rules you’ll be fine!

2. Stereo and amplifier minimum impedance ratings

All amplifiers of any type – where it’s a car stereo amplifier, home stereo receiver, home theater amplifier, and so on, have a minimum Ohms (impedance) rating. It’s important that you pay attention and don’t exceed the minimum speaker impedance rating.

This is because as the impedance is lowered, the electrical current increases, and therefore the stereo has to do more work. This increases the amount of stress and heat it has to handle.

If your stereo is labeled by the manufacturer as being “8 ohm speaker compatible” or similar, that means connecting lower impedance speakers can cause excessive heat and possible damage very quickly.

For example, connecting a 4 ohm speaker to an amplifier which is labeled as working with 8 ohm speakers would mean it would have to produce double the electrical current to the speaker!

Image of the rear of a stereo receiver and speaker impedance terminals

Image of the rear of a home stereo receiver/amplifier. The recommended speaker impedance ratings are usually listed above the speaker wire posts. A home stereo, for example, may often list 6-16 ohms are ok for using.

Also, attempting to wire 2 of 8 ohm speakers in parallel to an 8 ohm stereo would have the same effect. (2 8 ohm speakers in parallel is equal to 4 ohms total that the amp will see)

I’ve seen many attempts by people who had friends who claimed they could “boost the power” or “get more power” by some claimed trick, but it doesn’t work. They ended up with a destroyed amplifier.

An amplifier can only handle so much heat and stress before it fails, so be sure to observe these rules. Be sure you wire speakers to meet the minimum Ohm rating you need.

Remember: do not use a speaker impedance below the rating given by the manufacturer. Overheating or permanent damage can result. I have seen it happen!

3. What is speaker polarity?

Speakers are different than other devices in that they operate using alternating current (AC) rather than direct current (DC). This is good news! It means you can’t harm your speakers in most cases by having the positive (“+”) and negative (“-“) wiring reversed.

Unfortunately, it gets just a little bit more complicated when we use more than 1 speaker.

Speak polarity and why you should match speaker connections

As I mentioned, speakers operate by moving a cone, and they actually move back and forth in order to produce sound. If you wire 2 speakers in a stereo with different polarities (for example, one has positive and negative wired as labeled, and the 2nd speaker has the opposite) an interesting thing occurs: they are out of phase and some sound cancels out.

The end result is a strange and poor sounding stereo. In most cases you’ll notice a lack of bass sound and it won’t sound pleasing to the ear as expected.

Diagram showing speakers in and out of phase

When speakers are wired the opposite of each other sound waves cancel out. When wired the same, sound waves add together for more sound.

Speakers that are wired differently sound poor because much of the sound is canceled out. Basically, it’s simply because sound waves from one speaker are moving in the opposite direction of the other speaker – and if they’re close to the same time and frequency range, often they cancel out.

This is why when 2 woofers are placed in a box and are wired in parallel but with opposite connections to each other, they are “out of phase” and have almost no bass! It is because they are doing the opposite work rather than working together to produce more sound. While one is moving up, the other is moving the opposite direction, and so on.

So the the most important thing here to remember is: wire speakers consistently the same way as each other.

4. Wiring 2-way and 3-way speakers

2-way speakers, such as home stereo or car audio component speakers, are those which come as a pre-designed speaker set and use a crossover. The job of a crossover (also called a passive crossover, because it use basic capacitors and inductors rather than electronics) is to restrict the music production each speaker tries to produce.

For example, tweeters cannot reproduce bass frequencies (and can in fact be damaged by them) therefore a 2-way speaker crossover prevents this. Similarly, a woofer cannot produce high pitch sounds well and is prevented from doing so.

Unlike standard separate speakers, 2-way and 3-way speakers that have a crossover can only be used in parallel and not in series.

This is because unlike separate speakers with no crossovers in this case many sounds will be filtered out. What this means is that little to no sound would be produced if another 2-way speaker was connected in series.

Image for 2-way speaker diagram examplesTherefore if you have a home stereo or car stereo in which 2-way speakers are used, you’ll have to add more 2-way speakers (if the total impedance can be supported by the amplifier) or add more amplifier channels for more sound.

5. Doubling the number of speakers or amount of power does not double the volume

In some cases additional speakers can be added to increase the amount of volume you can achieve or to place speakers in additional rooms, additional locations in your vehicle, and so on. You also may have wondered what would happen if you bought an amplifier with twice the power of your present one.

There’s one important thing to understand, however: having 2 or 3 speakers instead of one does not double or triple the sound. It increases a few decibels for each speaker added.

Doubling the power does not double the volume either.

This is because of how the human ear works and the physics of sound, along with how speakers work and how much volume they can produce for a given amount of power.

Generally speaking, the human ear will hear a very small amount of volume increase for each doubling of acoustic power: approximately 3 decibels (dB). For most people the small amount of volume increase you notice when turning up a volume knob 1 notch is somewhere around 3dB.

Example volume produced by a typical speaker at different power levels:

  • 1W = 89 dB
  • 2W = 92 dB
  • 4W = 95 dB
  • 8W = 98 dB
  • 16W = 101 dB
  • 32W = 104 dB
  • 64W = 107 dB
  • 128W = 110 dB

So as you can see, doubling the amount of power you can drive a speaker at does not mean you’ll double the volume. It increases it a very small amount (as far as your ears are concerned).

You can also see from above that really cranking the volume takes a lot of power!

How to get more volume from speakers

The best ways to get more volume  in most cases are:

  • Use more efficient speakers (speakers that produce a higher dB volume at 1W of power – higher is better)
  • Add more speakers if you have an amplifier that can support it
  • Use higher-power rated speakers and a larger power amplifier if high volume is your goal

For most people an average and good stereo amplifier can produce sufficient volume to fill a room or vehicle and turn up the volume from time to time. I like to use 50W or higher per channel as a good rule of thumb when buying an amplifier.

How to read speaker positive and negative labels (+ and -)

Home stereo and car speakers normally often use a red or plus sign “+” to indicate the polarity for the speaker wiring terminals which you connect your wiring to.

Here’s a few things to know there as well:

  • In some cases, as black dot or a red or black stripe is used to mark the positive terminal
  • If a speaker has terminals of 2 different sizes, the larger of the 2 is normally the positive one
  • For speakers with wire already attached, typically the brass or golden-colored wire is the positive one
  • For speakers with wire attached but same colored wires, most have some small printing on the positive wire – be sure to check closely

Summary

Here I’ve provided you with a speaker diagram showing basic connections, I explained several important things you need to know about speakers and speaker wiring. Hopefully I’ve given you more understanding about how to connect speakers and get the most enjoyment out of your system.

Have suggests for this post? Still have questions? Be sure to leave a comment below or send me a message.

Confused about tweeters? Here’s a helpful guide explaining what tweeters are and what they’re used for.

Interested in bridging your car amp?  Find out how to bridge a car amp in this post.

12 Comments
  1. Thanks very much Marty you as an expert explained yourself clearly so as even a 73 year old I could replace the wiring correctly on my home stereo system.
    bob Sydney Aust.

  2. I’ve a pioneer vs8 hifi system which requires 16 ohm & 16 ohm+ rear speakers..I’m ignoring to
    Match power for those speakers…on the other hand the stereo spekears separately requires rms 60 watt. I wish solving the rear speaker matching troubles.

    • Great article Marty.
      I have a question for you. My Harley has a factory radio with 4 – 2ohm front and rear speakers. I am looking to add two more front lower fairing speakers.
      Without getting into an amp would it make since to change out the front speakers with high sensitivity 4 ohms then parallel my two add speakers that’s would be high sensitivity 4 ohms.
      That way my stereo would see 2 ohm resistance for the front and back speakers…
      any advice would be greatly appreciated….
      PS – I am ultimately looking for better sound not necessarily louder…

      • Hi Michael. I’m glad you like the article!

        If the front and rear speakers are all on separate left/right and front/rear channels from the factory radio, then yes you can use two 4 ohm speakers (in parallel) in the place of each original 2 ohm speaker.

        That depends on one thing, though: Whether or not each original speaker right now has its own channel. If not it’s possible that each pair of speakers are wired in series for a total of 4 ohms to the left & right channels (if the factory radio only has 2 channels and not 4, that is).

        If the factory radio has a fader (front/rear) control it should be 4 channels and your idea should work. I would definitely get the most efficient speakers you can find in that case as they’ll use a bit less power for the same volume.

        90dB/1 watt sensitivity is a good start but if you search a while you can probably find some good 92dB/1W speakers.

        My advice would be to try it and see how you like it and if the volume is enough. If you don’t get enough volume you can add a tiny but good amp like the Alpine KTP-445U for better sound on the road.

        I hope this helps!

    • Hello Shibli. I’m not quite clear on your comment. You don’t mention which speakers you’re trying to use when you are discussing “matching troubles.”

      Basically, just use speakers with the correct impedance rating. If you can’t, you may be able to add additional speakers.

      For example, if you have 16 ohm speakers and the stereo is rated for 8ohms, adding a 2nd pair in parallel would give 8 ohms.

      Thanks!

  3. hi,i have some ar 9ls speakers i took the mids out many years ago and cant remember which wires are which,one is green and one is white,could you tell me or anyone tell me please which one is positive and which is negative,thankyou,regards Matt

  4. Hey Marty…… Brother I have a serious question for you and I pray you will reply sometime before I get off work today….. cause I need to do this when I get home this evening…

    Ok…. I’ve already got a 4 channel amp installed and it performs beautifully…. But it only runs my 2 subs and 2 6x9s in the rear of the car….. I just got a 2 channel amplifier for the door speakers and the dash tweeters…. But I have no more rca outs on the back of the head unit…
    Since the 4 rca outs are currently running the rear only…. Can I use the speaker wire from the head unit or from the wiring harness of the vehicle and wire it to the high end of the new amp for the doors and dash…. ?????

    • I have a 400 watt rockford fosgate 4 channel amp that will put out 75w×4@4Ω/100w×4@2Ω or 200w×2@4Ω bridged. Im trying to install a componet speaker kit that includes a pair of 6 1/2″, tweeters, and crossovers rated at 210 watt peak and 70 watt rms @ 2.3Ω. A pair of 4×6″ rated at 120 watt peak and 40 watt rms @ 2.3Ω and a pair of 4″ rated at 105 watt peak and 35 watt rms @ 2.3Ω. My question is what would the most effective way to hook this up. I greatly appreciate any advise given.

      • Hi there Kevin.

        I would say it partly depends on the setup you want to use. For example, are the extra speakers going to be used in the front or rear?

        In your case I would run the 6.5″ component speakers off of the front channel and the remaining 4 speakers (6×9″ & 4″) in parallel for 2 ohms on the rear channels. You should be able to do that with your amp without any problems.

        This way you’ll have full power to the front components with the front channels and be able to do a front/rear fade control as well. (The rear speakers will share the available power on the rear channels, by the way).

    • Hi David! So I’ll answer your question:

      1. YES, if the 2-channel amp you bought has high-level (speaker-level) inputs you can run the speaker wiring signal to the 2 ch. amp for front channel use. RCA (line-level) connections are preferred, but this should be fine also. There’s absolutely no problem doing this.

      2. You don’t say how many RCA jacks you have on your head unit, but if you have 4 here’s how I would do it:

      – Front RCA outputs to the 2 ch. amp for front speakers
      – Rear RCA outputs to the 4 ch. amp, using either 2 x female-to-male Y adapters right at the amp. (Or if the 4 ch. amp has a 2/4 channel input switch, set it to 4 and use it that way.)

      If you do need to use speaker-level connections, the great news is that you won’t need large gauge wire, so don’t waste money on that. You can use a much smaller gauge for speaker-level inputs if you like.

      I hope this helps! 🙂

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