How To Connect 2 Speakers To One Output – All You Need To Know!

In this article I’ll cover all the details needed for connecting two speakers to one stereo or amplifier channel output. Despite some claims out there, it’s not as simple as they’d have you believe!

Read on and I’ll explain why. I’ll show you the pros and cons of series vs parallel speakers along with how to get the best sound or simplest connection based on what you need.

Can I connect 2 speakers to one output?

Basic facts first
The short answer is generally yes, but it depends on several important things such as the minimum Ohm rating of the receiver or stereo amp, the type of speakers, and the speaker Ohms rating.

The type of speaker and how it’s connected can affect the quality of sound you’ll get as you’ll see below.

What happens if you connect two speakers to one channel?

two speakers in series or parallel impedance diagram illustrated

When two speakers are connected to one channel it will see a speaker load (total Ohms load) that’s lower or higher than one speaker alone.

This is because either more or less electrical current is flowing depended on how they’re connected. The end result is that the amplifier does more or less work.

  • For speakers connected in parallel, the total Ohms impedance is lower. It is the speaker Ohms divided by the number of speakers. More electrical current will flow if the radio or amplifier can supply it.
  • For speakers connected in series, the total Ohms impedance is higher. It is the total of the speaker Ohms all added together. As the total resistance (speaker impedance, in Ohms) is increased, this means less electrical current will flow.

If the total Ohms load seen by the output channel is too low the audio device can overheat and suffer permanent damage.

If the Ohms load is higher, it’s safe – the amp will simply produce less total power. Each speaker will receive less power than it would when connected alone (usually 1/2 to 1/4 of the full wattage).

How power is shared between parallel or series speakers

diagram showing how power is shared between series or parallel speakers

One thing to know is that you can’t get free power – connecting two speakers to one output channel means they will have to share the available power.

Remember these basics:

  • Parallel speakers share the output power for the total speaker load. For example, connecting two 4Ω speakers in parallel means a total of 2 ohms. Each speaker would then get 1/2 of the rated power output at 2 ohms.
  • Series connected speakers receive less power overall because the total power to all is lower than parallel speakers. For example, two 4 ohm speakers in series add to an 8 ohm total load. Power output at 8 ohms is 1/2 that of 4 ohms (due to Ohms Law for power), with each speaker having 1/2 of that.

When connecting 2 speakers to one output channel it’s a compromise you have to live with. A car stereo, home AV receiver, or home or car amplifier is often designed with one speaker per channel in mind.

How to connect 2 speakers to one output

how to connect 2 speakers to one output diagram

Steps to connect multiple speakers to one output in parallel or series

Series:

  1. Strip the wire insulation to bare wire and connect one speaker wire to the positive terminal of the output then to the positive terminal of the first speaker.
  2. Keep (or cut) enough length to reach the second speaker. Connect the negative terminal of the first speaker to the positive terminal of the second speaker.
  3. Connect the negative terminal of the last speaker to the negative terminal of the output.

Parallel:

  1. Connect a speaker wire to the positive terminal on each speaker. Both speaker’s positive wires should connect to the same positive terminal.
  2. Connect a speaker wire to the negative terminal on each speaker. Both should connect to the same negative terminal at the output at the amp.
Important! ONLY wire speakers in parallel if the stereo or amplifier can handle the Ohms load you’ll be using. Always check the output label or specifications before doing so.

example of speaker Ohms ratings on a speaker box and a home receiver

When connecting two speakers in parallel to an output, remember to divide the speaker Ohms rating by two to know how much your receiver, radio, or amplifier will need to be able to handle.

When to use a parallel connection or a series connection for speakers

single cone vs 2-way speaker comparisons image

Image showing single cone vs 2-way/coaxial speakers.

Single cone speakers don’t have an additional tweeter like you’ll find in a 2-way stereo pair speaker set or car audio coaxial 2-way speakers. While that might not seem important at first, 2-way speakers always use at least a tweeter crossover and in many cases a woofer crossover as well.

Speaker crossovers use inductors and capacitors which will affect the sound when connected in series as I explain in the next section.

Here are some guidelines to follow for series vs parallel speaker wiring:

  • If your radio, amp, or AV receiver can handle the Ohms load of two speakers in parallel that’s the better option. You’ll get more power to each speaker vs. series wiring.
  • When that’s not an option, or if you’re unsure, connecting speakers in series is a safe bet. They’ll receive less power but there’s no risk of damaging the output electronics.
  • Connecting 2-way or 3-way speakers in series will work to produce sound but the sound quality will suffer. I’ll explain more in the next section.
  • If sound quality isn’t a big deal for you and your amplifier or stereo can’t support the Ohms load of your speakers in parallel, wiring them in series is ok in most cases.

Why 2-way or 3-way speakers have worse sound in series

parallel vs series speaker wiring sound quality problems diagram

As I mentioned earlier, connecting 2-way or 3-way speakers in series usually isn’t a great idea. That’s because they use capacitors and inductors as speaker crossovers to control the sound directed to the tweeter speaker and the woofer.

The problem is that a speaker crossover expects to see a fixed speaker Ohms amount in order to work as expected. When that speaker Ohms impedance changes, something called crossover shift happens. This simply means that the crossover frequency will change – and it can change a lot!

Home stereo tweeter with capacitor crossover

Example of a 2-way speaker’s tweeter with its capacitor crossover attached.

For example:

  • If a tweeter and its crossover are connected in series with another similar tweeter & crossover, the Ohms value can double. The crossover frequency will go down by twice as much, letting unwanted midrange, etc through.
  • If a woofer has an inline crossover inductor, connecting two speakers in series will double the total speaker load, meaning it will be affected as well.

That’s not to say you can never connect a 2-way home or car speaker in series, and in some cases it’s not a huge deal, but it shouldn’t be your first choice when you’ve got other options.

Fortunately, there’s a great workaround that’ll give you the best of both worlds (the right speaker load and the same sound quality).

How to use 2-way speakers in parallel for great sound AND no Ohms problems

diagram of how a speaker impedance adapter can be used

Example of a speaker volume control with an impedance adapter connected to a 2 channel amp. With this type of adapter two 8Ω speakers wired in parallel (4Ω total) will appear as one 8 ohm speaker to the source.

You can use an impedance adapter to ensure each speaker is wired in parallel on the output side for best sound quality and so the amp or stereo sees the correct load impedance.

An impedance adapter uses small transformers to convert the input and output sides to match the impedance load. Depending on the options, some even allow using 4 ohm speakers with an 8 ohm amp and vice versa.

They’re also really handy when using additional speaker pairs in your backyard or pool via a speaker selector switch.

Why is it bad if the speaker impedance is too low?

What happens if using a higher or lower speaker impedance diagram

Using a lower speaker Ohms load than a stereo or amplifier is rated for is bad because it causes the radio or amplifier to attempt to put out much more current than it’s rated for.

When the audio output transistors are forced to try and handle too much current due to a lower speaker Ohms load they become super hot and start to break down. It doesn’t take long before the damage is permanent and they no longer produce sound at the speaker output.

More great speaker wiring articles

Your comments are welcome!

  1. Thanks for being so helpful!
    Question, would the Rockville VOL70100 100 Watt 70 Volt Wall Volume Control Zone Controller Box 1-Gang be an appropriate controller to use?
    Thanks!

    Reply
    • Hi John. The Rockville is for 70V speakers systems like you’d find in offices and buildings, so it doesn’t have the right transformers for standard home stereos etc. The one in the picture in my article is the Audtek VRS100 (100W rated).

      You can also have a look at the Audtek VC-100R as well. Parts Express keeps several types in stock and they’re pretty affordable too. :)

      Reply
      • Hello Marty my name is MARK Avalos, I enjoyed the article thank you so much I need help! I have a Denon AVR Home theater 5.1 system, my existing five speakers are three way speakers, the speaker ratings on the rear of the unit states Impedance of 6~16, and I’m looking to purchase a pair of two-way Klipsch speakers rated as 8ohm 2 way speaker set, my question is if I have these wired in parallel would I be OK? I’m not sure if I could remember how to get back to this web page to see the answer could you please kindly reply back to me at my email please?🙏🏼
        at [email removed] make the subject on the email, answer to your Home theater speaker question, so I don’t think it’s spam please! I could really use the help on this! I hope to hear back from you by email sir, 🙏🏼

        Reply
        • Hello I responded by email. I cover this in the section “How to use 2-way speakers in parallel for great sound AND no Ohms problems” above.

          Best regards.

          Reply
  2. I have a 4 channel amp rated at 80w rms @4 ohms per channel. I have 2 sets of 50w rms 4 ohm speakers.
    Would it be possible to run 1 set per channel without any issues, and obviously not using 2 of the channels.

    Reply
    • Hi, if it’s 2 ohm capable yes you can run them in parallel off of the channels you want. Otherwise no you can’t, or at least not without having to use power resistors in series with each speaker.

      Reply
  3. Hi Marty – Need some advice for my car system. I have a Hybrid Audio U4A amp which has 2 Ohm RMS Output when running in 4 Channel Mode (see link to manual below). I currently have 4 (2: 6.5 inch & 2: 3.7 inch) speakers in the car system would like to connect 2 more speakers (6 total) in parallel without damaging anything. I was thinking of adding them in parallel and connecting them to the Front/dash Unity U3 Crossover(s) connection.

    2 Rear speakers – Hybrid Audio Unity U6 (currently installed) 6.5 inch.
    2 Front/dash speakers – Hybrid Audio Unity U3 (currently installed) 3.7 inch.
    Want to ADD: 2 Door Speakers – Hybrid Audio Legatia 5.25 inch midrange.

    Based on the above, I should be able to add the 2 speakers as noted, correct? Thanks very much!

    Reference:
    Unity U4A Amp: https://hybrid-audio.com/files/manuals/03_Unity-Amplifier-Manual.pdf
    https://docs.google.com/spreadsheets/d/171U5hnXCQvEhZEljsfZAHZbwA5E3eaW0JUgkidnD4L8/edit#gid=1658604352

    Reply
    • Hello there, Tim. It depends on what type of setup you’re after. I say that because having looked up the U3 and you having mentioned a crossover, I see this regarding the Unity 3.7 speakers: > “Also available are the U2x-W and U2x passive crossovers…

      So it would be one of the following:

      1. If you only want to add the 5.25″ in parallel, and you’re not after a 3-way system or etc., then yes you can just wire them in parallel to the full-range output of the amp/speaker terminals (2 ohms total).
      2. If you’re after a 3-way (or other) type of setup and want to use a speaker crossover, you’ll simply use it with the crossover’s output.

      For #2, the total impedance seen by the amp for a 2-way or a 3-way speaker system would be the impedance of whatever the speakers are. For example, let’s say I have a 3-way speaker setup with a 3-way crossover and 4 ohm tweeter, midrange, and woofer. The amp would see 4 ohms total for that system with the crossover in use.

      If there’s a misunderstanding let me know and I’ll try to answer based on your needs. Best regards!

      Reply
      • Really appreciate the insight. All current speakers came with crossovers (except the new 5.25 inch) and all 6 of them have an impedance of 4 (per that google doc spec sheet). Looking for the best audio experience, so it sounds like the 3-way setup (with crossovers) would be best. I am trying to avoid overloading the amp and damaging it, so I was looking to confirm that the amp can handle wiring the new 5.25’s to the 3.7 speaker crossover. I am new to all of this, thanks again.

        Reply
  4. Hi there. I’ve only connected the speakers to one channel because when i try to connect to both, only 1 speaker works at a time. There are 5 combinations. A, B, C, A&B, A&C. Only when i plug both of them into A do both speaker work. BUT, there are certain records that when I play, the vocals come in much lower than the music. Could that be a function of the actual album, or the fact that I’m doubling up?

    Reply
    • Hi Tom. It’s hard to comment about the situation with your speakers only working with “A” without more info.

      Regarding the vocals issue, that’s usually what happens when playing stereo music only from one side. Some music contains the vocals or other audio more on the other channel, meaning if some sound can be much lower or missing. You’ll need both L & R sides to hear everything (unless the audio source is mono).

      Reply
      • Hi Marty. Turns out I ain’t too bright and get confused easily with vertical and horizontal. If I had just simply put the wires on correctly, meaning on the vertical line instead of horizontally…no issue at all. Only took a month for me to figure out!!

        Reply
  5. Marty, can you use an ohmmeter to measure the combined impedances of speakers wired in series vs. parallel? Maybe there is no need to do this since the values can be calculated, but it would make me feel better, and satisfy a certain curiosity, to be able to “see” the actual impedance values. Thanks.

    Reply
    • Hello Donn. You can if none of the speakers have crossover with capacitors in series with them. Otherwise it won’t be right as capacitors appear as an open circuit to a resistance measurement.

      Bear in mind that what you measure with a test meter will be only the DC resistance of the voice coil itself and not the total impedance that would be present with a music signal applied, although it’s usually not a large difference. Also, the measured resistance is typically below the generic impedance rating listed such as 4Ω, 8Ω, etc.

      Reply
    • Hi Ryan yes you sure can. The total power delivered to speakers in series will be lower, however, so be aware of that. Best regards.

      Reply
  6. Hi, Marty,
    Thank you for your time to make this explanation. Now I start to see my worries which I didn’t think before I read your article here.
    I connected two 8 ohm speakers ( one is Orb satellite and the other is Polk Audio tsi200) to Denon AVR X1400H (output is 80 Wpc at 8 ohm and it handles 4 ohm to 16 ohm) just to make the sound more spacious feel by spreading the speakers ( so I have two L and two R total speakers).
    To make things right, I need to add an Impedance adapter ( as you suggested).
    1. Where can I buy those and is there different kinds that I need to specify when I buy, or just any adapter will do?
    2. If I am upgrading to 300 W per channel amplifier in the future, can I do the same ( keep the same speaker setup) or should I worry about the higher wattage amp damage more. What should I do if I still want to keep two speakers per channel?
    Thank you for your advice
    Don

    Reply
    • Hi Don.

      1. As long as it can handle the impedance matching you need and power rating for your receiver or amp, it should be fine. Here’s one for example: https://www.parts-express.com/Audtek-VC-100R-Impedance-Matching-Rotary-Speaker-Volume-Control-100W-300-566

      2. Hmm, I think in this case you might need to try searching for a higher power impedance adapter, but I think those are very rare. You might need to just get at least a 4 channel (or higher) amp in that case to make things easier.

      (Note: Harder to find adapters, transformers, etc. tend to be rather expensive so I think you’d come out head with a multichannel amp in that regards also for #2.)

      Reply
  7. HI @Marty,
    You have explained great and need your suggestion in my case.
    I have 9 in-wall speakers (2-way). All of them are same. I feel centre channel is not enough so I’m
    thinking to add another same speaker to centre channel.
    My setup :
    Speakers: JBL 8IW – 8 Ohm/100 Watt
    Receiver: Onkyo nr7100 – Supports 4Ohm.

    As you suggested, joining them parallel is the best way to go. Result will be 4 Ohm.
    My Question:
    1. Is there any smaller fixed Impedance adapter available to convert 4 ohm to 8ohm so I can just attach inside speaker and put insert into wall ?
    2. Receiver has two settings “4 Ohm” and “6 Ohm and above” Receiver only set it globally.- Can I run one 4 ohm speaker (without any adopter) and all others on 8 ohm?
    3. Cant it simple to add a register in series like this – https://www.parts-express.com/4-Ohm-20W-Resistor-Wire-Wound-017-4

    Thankyou.

    And another followup question: Most of centre channel I see, have only one tweeter and two or more woofers. When adding two speakers, should I keep two tweeter, or just disable/bypass one tweeter.?

    Reply
    • 1. You can use a speaker impedance adapter such as the one shown in my article. Here’s one for example.

      2. If you set the receiver to 4 ohms you should be able to connect 8 ohm speakers without a problem.

      3. I’m not sure I understand the question. For which problem? You can connect series resistors with a speaker if you need to bring up the total Ohms load, yes.

      4. I would probably just keep the tweeter. For decent speakers the sound should still be good.

      Best regards!

      Reply
  8. I have Amplifier Lab.Gruppen C 10:8X 1,000W 8-channels: A, B, C, D, E, F, H, G; each channel I believe is 125W
    The sound company set up 8 speakers Tannoy CMS803DCQ on the ceiling of the church. They connected 2 speakers to channel A, 2 speakers to channel B, 2 speakers to channel C, 2 speakers to channel D. Two channels F and H connected with 4 Tannoy CMS 403DCE.
    Now there are H and G channels left open. I want to have 4 other new speakers to be installed in our choir stall. I would like to buy “Tannoy AMS5ICT 5″ 2-Way ICT Passive Wall-Mount Speaker 70V”. We need sound good enough to hear, not loud, most of the time we read and want to hear whatever read.
    My questions: Is it ok to buy Tannoy AMS5ICT 5″ 2-Way ICT? How do I connect them? Should I connect them as the sound company did?

    Reply
    • Hi, I’m not sure how they connected the CMS803DCQs to the amplifier but most likely you would do the same (I don’t see those details in your post).

      The AMS5ICTs should be fine to use and can be connect more than one way – like standard speakers or using a 70V connection/setting. If they’re going to be wired for a long installation length 70V is often the best way. But if not you can wire them in 16 ohm mode, two per channel, since the amp can handle 8 ohms.

      Best regards.

      Reply
  9. Hi Marty!
    My intense googling took me here, and I hope you can help me out :)
    I’m building a portable speaker (slightly smaller than a suitcase) and have run into an “issue” with the speakers. I can’t figure out how I’m supposed to hook everything together without killing anything.
    I have :
    – 2x100W, 4Ω mini amp
    – 1 pair (2) of 4Ω speakers (3way)
    – 1 Pair (2) of woofers 8Ω
    I’m clueless as how I don’t burn anything down, or mess with the crossover of the 3ways, but still having the Ω ohms about the same

    Reply
    • Hi unfortunately there’s not a good way to do this with a 2 channel amplifier. Ideally, woofers or subwoofer are used with a low-pass crossover for the best sound – especially considering you’re already using 3-way speakers.

      Another problem is that the woofer impedance is different from that of the 3-way speakers meaning the woofers will not receive the same amount of power from the amp. It’d be better if you used 4 ohm woofers or add another pair and wire each pair in parallel for 4 ohms total. But you’ll need another 2 amp channels either way.

      Reply
  10. Hi All, I would like to connect 2 speakers on my bike’s fairing and the plug in my ipod, what is the best way to do that please.
    A1Foxxy

    Reply
    • Hi there you could use a compact/mini amplifier to do so, especially one with Bluetooth functionality built in if you like. There are some good choices out there for motorcycles and other outdoor vehicles that are relatively easy to install and resistant to moisture etc as well.

      If you don’t have Bluetooth you can use an auxiliary input to the amp (RCA jacks and cable to your iPod).

      Reply
  11. I have two McIntosh MC7270 amps and four 8 ohm Klipsch Cornwalls. Which is optimum, bridged mono or stereo mode? Thx

    Reply
    • Hi Jonny. In this case as you say you have two of the amps, it can handle 4 ohms, and you’ve got 2 pair of speakers I’d wire each amp in mono bridged then two speakers paralled on each amp for a 4 ohm load. Then one stereo channel to each amp.

      That way you’ll have 270W available to each speaker and still have nice stereo sound. Best regards.

      Reply

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