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

We all enjoy music and speakers make that possible – but it’s confusing if you’re not sure how to connect them the right way.

In this post, you’ll find clear and detailed speaker wiring diagrams to help (and that you can 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 simple once you learn the basics.

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.

Example of a speaker voice coil close up

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 extra math needed to figure out the total resistance.

The word used to describe this is called impedance.

Speaker impedance is just a more advanced way of finding the total resistance, and by tradition is measured in 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 understand 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 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 that 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 as being ok for use.

Also, attempting to wire two 8 ohm speakers in parallel to an 8 ohm stereo would have the same effect. (Two 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 burned-out 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: don’t use a speaker impedance below the rating given by the manufacturer. Overheating or permanent damage can result. I’ve seen it happen!

3. What is speaker polarity?

Speakers are different than other devices in that they work using alternating current (AC) instead of 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 work by moving a cone 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’re out of phase and some sound cancels out.

The 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’s 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 most important thing here to remember is to 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 can’t reproduce bass frequencies (and can in fact be damaged by them) so a 2-way speaker crossover is used to prevent this. Similarly, a woofer can’t 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 is connected in series.

Image for 2-way speaker diagram examples

Therefore 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, more speakers can be added to increase the amount of volume you can get or to place speakers in more rooms, more 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 (dB) 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: about 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 a lot more volume is your goal

Most people need an amplifier that can produce enough 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 are a few things to know there as well:

  • In some cases, a 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 the 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 questions, comments, or suggestions? 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.

Your comments are welcome!

  1. Hi. Im renovating a jukebox . The old amp died so Ive purchased a new amp with 250 watts RMS at 4 ohms or 150 rms at 8 ohms per channel.

    Can I wire 2 – 5 way 4 ohm Boss car speakers in series on one output channel and wire a single 8 ohm woofer on the other channel.

    My concern is will the two 5 way boss speakers work ok wired in series

    Reply
    • Hi Michael. When you wire 2-way or other similar type of speakers in series it can affect the sound. That’s because the crossovers will end up connected in series, meaning the sound will be affected by both the additional speakers & crossovers. By using only one channel you’ll also lose the stereo sound so it’s not a good idea anyhow.

      You’d probably be better off getting an additional small amp for the woofer. A plate amp (used to build your own powered subwoofer) is one option to consider.

      Reply
  2. Hi Marty
    I purchased and repaired a Craig S200 FM/8 Track . The wiring from the Z403 mounting kit has a single front common and a single rear common with a shared connection for both left front and rear and right front and rear speakers. The service manual shows output impedance 2-8 ohms. With the front and rear speakers both sharing the common wire and both speakers on the left and right sharing the same signal wire, I was planning on putting 2 PLMR24 mini box speakers in the front and 2 more in the back. These are 4 ohm speakers and I don’t want to hurt the S200. Any wiring suggestion is appreciated. FYI the front common had to be tapped into to supply a ground for the system.

    Reply
    • Hi, what wiring colors does it have specifically? If it has a 4 channel output then you’d have one positive wire per speaker if I’m not mistaken, based on looking at other units like it. If it’s only a 2 channel you and you want to keep the impedance above 2Ω, you could connect a series resistor to each speaker (say 2 ohms each) and wire the speaker pairs in parallel. That would put the impedance load at 3 ohms but I don’t think that’s nessary.

      Yeah the unit was likely grounded through the chassis or car antenna.

      Reply
  3. Thank you for the reply.
    I hooked it up as listed below, I don’t know if it is serial or parallel but tested to see if there was sound.
    I guess the unit is 2 Channel, there is no fade front to rear, “default” switch settings have sound from only the front speakers if hooked up with orange to both front speakers and green and grey to the left and right even though the rear speakers are hooked up with black to both rear and brown and white to the left and right, until the “stereo” button on the deck is pushed, then there is sound from all 4 speakers.
    The schematic has heavy line to the 03 – Black connection and does show it going to ground.

    10 / 09 – Antenna
    06 – Orange R Com (I took this as rear Common)
    05 – Brown R L CH (I took this as rear Left Channel) / Green F L CH (I took this as front Left Channel)
    04 – White R R CH (I took this as rear Right Channel) / Grey F R CH (I took this as front Right Channel)
    03 – Black F Com ( I took this as front Common)
    02 – Red + B ( I took this as Battery Power)

    There are 10 connections in all, the ones not listed do not have wires attached to them.

    Thank you again for your assistance.

    Reply
    • Hi Bob. I was reading a bit more and I think the stereo button is for when you’re not using quadrophonic 8 track cassettes. Which makes sense as you’d have to duplicate the regular stereo signal to the back 2 channels. At least that’s what I believe is happening. (A similar mode is needed sometimes for today’s home theater receivers when you don’t have a surround sound signal – it sends stereo to the rear/surround speakers)

      I think you have the wiring right. So in this case I believe you’ll be fine just using one speaker per channel. It sounds like it doesn’t offer a fader, but if you need to drop the volume to the rear speakers you could. There used to be some aftermarket rear fader controls years ago (from Radio Shack etc.) but I haven’t see those for a long time.

      Alternatively you can use a resistor to each rear speaker to bring them down in volume if you like. using a 60 ohm one would give -24dB, for example.

      That’s a cool project you have I hope you enjoy the sound. I’m very curious how it sounds! My mother had some 8 track cassettes still around when I was very young.

      Reply
  4. Thank you.
    The current install is in a 1965 Shelby Cobra kit car, that’s why the indoor/outdoor mini box speakers.
    The other install will be in a 1969 Dodge Charger with some Pioneer speakers I have been using since the 80’s.
    Somehow I don’t think I will need to bring the speaker volume down on the rear speakers, the Cobra side exhaust ends right by the seats.
    The service manual says the output power is “4.0 watts average continuous sine-wave power per channel”. The Tuner Stereo Switching states “Automatic, with STEREO defeat switch.
    I doubt I will be winning any stereo battles with this but it does look right at home under the dash.
    I miss Radio Shack when messing with things like this, all component repairs require finding them on the internet and hoping they are available somewhere other than China.

    Thank you again for all of your help, I will get things final wired, mounted and throw in an 8 track. Maybe a little Surf and Drag. Have a Great Weekend.

    Reply
  5. Hi, I am confused and need some assistance. I am installing a Sonos amp with 4 Klipsch AWR-650-SM outdoor speakers to surround the pool.

    Each speaker has 4 wires,
    (Red +)
    (White +)
    (Green -)
    (Black -)

    There is a diagram for 1 and 2 channel wiring but I have no clue what this means or how many speaker wires that I need to run.

    Can you please offer some guidance??

    Reply
    • Hi, so basically from the owner’s manual, we can see that if you use one speaker per channel the amp will have to be 4Ω stable per channel. The speakers would be wired amp positive -> speaker red& white. amp negative -> speaker greed & black.

      To use them normally (8Ω capable amplifier) you’d use one amp channel pos.-> white, negative -> black. 2nd amp channel pos. -> red, 2nd. amp ch. negative -> green. So in that case you’d need 8 amp channels total to connect four speakers that way.

      Reply
  6. Hi , I have some old speaker that were made by Power Voice Systems which I can find nothing about. They have no information on them anywhere inside or out. They consist of 2 15 inch speakers, a horn and 4 little somethings across the top. If I check resistant in ohms I get 6.9 but don’t think this is a correct reading. I would like to know how to tru test them and figure out what I have

    Reply
    • Hi Kenny. If you measure 6.9Ω they should be 8Ω speakers. You’re likely measuring the DC resistance of the woofer voice coils since they are either directly connected to the terminals or have an inductor inline with them. The tweeters normally appear as an open circuit when checked since they use a crossover capacitor.

      The alternative is removing them and disconnecting at least one speaker wire then measure them right at the speaker. But it may be stamped or printed on the drivers also.

      Reply

Leave a Reply to Marty Cancel reply