The calculator below is useful in determining the total impedance of speakers in parallel. It also calculates how the power is shared between the speakers. If all the speakers have the same impedance, the calculation is relatively simple.

### Simple Impedance Calculation for Speakers in Parallel

If all the speakers in parallel have the same impedance, then the calculation is easy. Simply divide the impedance by the number of speakers in parallel.

Example 1: Four 8 ohm speakers in parallel: 8 divided by 4 = 2 ohms.

Example 2: Two 4 ohms speakers in parallel: 4 divided by 2 = 2 ohms.

### Not so Simple Calculations for Speakers in Parallel

For calculations involving speakers in parallel with different impedance, the following formula is required (it can be used with speakers of similar impedances too).

If you have a calculator with *1/x* button then this calculation is not too difficult. If you don’t have that function on your calculator, or if you don’t like formulas, check out the calculator below.

### Using the Calculator

The calculator can be used for 2, 3 or 4 speakers wired in parallel.

Simply type the impedance of each speaker into the white boxes (or use the drop-down values). Use N/A for unused speakers in this calculator. The total impedance will be calculated for the entered speakers.

Also calculated for each speaker is its percentage share of the amplifier’s output power. This is useful as power sharing is a consideration when using speakers with different impedance.

“Power Differential” is the final calculation. This calculates in dB (decibels) the power level difference between the highest and lowest power as it is shared across the speakers. This shows the power level difference when using speakers with different impedance.

###### Amplifier Power Calculator

The bottom section of the calculator helps in matching the speaker combination with your amplifier. This is not necessary if you only want to know the total impedance and/or the power ratios.

However if you are connecting these speakers to your amplifier, it may be helpful to input the amplifier power and the associated speaker impedance. In the specifications for your amplifier, it should say something like:

Amplifier power: 80 watts continuous average power @ 4 ohms (2 channels driven, THD 0.08%, 20Hz-20kHz)

This tells you the maximum continuous power the amplifier will deliver into a 6 ohm load is 80 watts. In the calculator below, for this example, you type in 80 for the power and 6 for the impedance. Be aware, some specifications state RMS power rather than continuous power. These are effectively the same.

The calculator will display the effective power of the amplifier for the calculated total impedance of the series speakers. Also displayed (under each speaker’s power %) is the actual maximum power the amplifier will supply each connected speaker. A comment on the suitability of the calculated total impedance for your amplifier is also provided.

Download Calculatoras Excel File |

`Prices in US$` |

Note: the calculated output power for the amplifier is based on a theoretical “ideal” amplifier. In practise, your amplifier may produce slightly more power.

###### Further Reading

This calculator will help you understand the total speaker load on your HiFi amplifier. For a better understanding of this and what to do about it, read the articles How do I Connect Multiple Speakers to my HiFi Amplifier and How to wire four HiFi speakers or How to connect 2 speakers to one amplifier or watch the video in the article Understanding Speaker Impedance.Also see How Multiple Speakers Share Power for further details about the percentage power calculations. For more details about the effective amplifier power at higher impedance loads, see How Impedance Changes Amplifier Power.

Please Note: all these calculations are for connecting manufactured speakers (boxes). They are not used when building your own speaker boxes and connecting multiple speakers in a cabinet using a crossover circuit. A crossover splits the signal into different frequencies for each of the speakers and makes the total impedance calculation complex (as impedance is frequency dependent). That is why speaker designers get the big money, and as installers we benefit from their expertise.

If you need further advice on connecting speakers (boxes) in parallel, please read the FAQs before submitting your question. You may also find an answer in the comments below.

**Please Note:**During the Covid-19 crisis I'm very busy with a number of streaming projects, and have very limited time to attend to this website.. I'm currently over a week behind in answering questions and may not get to them in a hurry. Sorry for any inconvenience.

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European and Australian readers can use the links on the side panel - Thanks for the support

Sir i have 2 speaker of 20w 16ohm and 2 speaker of 40w 6 ohm, then how can i take them in my use with phone, and how much sound amplifier is required for them

Hi Nishchay,

I suggest you only use the 6 ohm 40 watt speakers. Connect these to any stereo amp, anything from the 10 watt to 60 watts will work. But don’t turn it up so load that it distorts as distortion is a sing of overloading.

Geoff

Hello sir,

I have 3 Ahuja 65 watt 8 ohms speakers and I have a amplifier output 200 watt 4ohms and 8ohms selection. How can I connect 3 drive units (speakers) to this amplifier. How can I match the impedance so that I can connect in 4 ohms or 8 ohms.

Hi Pinkesh, You have found out that it is not possible to wire three 8 ohms speakers to make the total load impedance 4 ohms or 8 ohms. If you wire all 3 in parallel, then the total impedance will be 2.7 ohms – too low. If you wire them in series, the total will be 24 ohms. This will work with most amplifiers but it will not be as loud as it could be. It would be best to only use two speakers. Two 8 ohm speakers in parallel gives a total load impedance of 4 ohms, which will… Read more »

Hello Geoff, I have a question I’ve recently bought a pair of JVC Model Sp-HXZ1 speakers. The speakers contain a sub-woofer rated at 150W at 6 ohms and has the main speaker rated at 50 W 6 ohms. My receiver is a Sony STR-DH750 which is rated at 6 ohms. Wiring up the one jvc speaker with both of its internal speakers in parallel will put it at 3 ohms, which my receiver obviously cannot handle . Likewise, putting in series will raise it up to 12 ohms, which is not ideal. My question is, If I wire the speakers… Read more »

Hi Christian, The speakers you have were designed to go with a matched amplifier which had separate amps for the sub and the main speakers. Which meant the amp also separated the sub frequencies from the other frequencies. Without this separation, both speakers will get the same program. Running both together with same program will cause them to sound different to how they were designed. Having said that, there is no technical reason why you can’t join them together, as long as you watch the impedance which you are doing. I would caution running them in parallel for the reason… Read more »

How to calculate for this tripple voice coil each coil 8 ohms:

http://www.ecoustics.com/electronics/forum/home-audio/646685.html

Best way to wire for typical amplifiers ?

Hi, It is difficult to be certain without knowing the exact specs of the speaker. Most multi-meters only read DC resistance, not impedance which is dependent on frequency. Normally DC resistance reads lower than AV impedance. Not withstanding the issues with impedance, it would be difficult to also know the power ratting of each coil. If you connect an amp across one set of terminals it should work. Then bridge it to a second set of terminals also, and should sound a little b-t louder – by 3dB. Without knowing the specs, I would be play it safe and just… Read more »

Hi Geoff,

I’ve got a question about a setup we are doing… we have a 1,000 sqft banquet hall, we’d like to put 8 speakers in the ceiling, 4 in each side (4 left, 4 right). What do you recommend as far a wiring and an amplifier. Mostly used for a microphone setup and music.

Thanks!

Hi Paul, Normally for a function room I wouldn’t worry about stereo – on the basis no-one is standing equi-distant between the left and right speakers to appreciate the stereo. You are better off having all the program coming from all the speakers – on the basis everyone is standing or sitting near a speaker, provided your speaker spacing is correct. Therefore I would use a distributed speaker system. If you want a quality result, I would suggest the JBL Control 26 CT’s. These are a professional ceiling speaker ideal for your situation. Make sure you get the model with… Read more »

Hey Geoff, awesome website. I have a quick question about a 6 speaker setup I’m contemplating. It goes as follows: I have two identical guitar cabinets, 3 speakers a piece. Each cabinet runs 2 x 16ohm and 1 x 8 ohm speaker wired in parallel, coming out to a 4 ohm load. Cool. My thought is to wire the two outputs from each cabinet (4 ohms each) in series, combining the cabinets to make an 8 ohm load. My plan was to take positive from cabinet one and negative from cabinet two for the main output, and then cross the… Read more »

Hi Sterling, Your idea is fine. That is certainly one way to connect two speakers in series. Other ways can be found in my article on connecting 2 speakers. There are two slight issues which may or may not concern you. Connecting speakers in series will affect the damping factor, which affects how tight the bass sounds. This is not a concern for domestic installs but it could be for you especially if using a bass guitar. The other issue is that you will get less level from each cabinet than you do with only one connected. Firstly, by having… Read more »

Hi Geoff, I love the website and all the information. Great stuff! In short, I’d like as much information as you can offer about my inquiry. I am using a 300 watt Tube amp – Ampeg SVT 2 PRO. Cabinet A – Ampeg SVT 410HE – 500 Watt – 4 speakers – 32 ohm each – Final impedance @ 8 ohm. Cabinet B – Self made – 2 Speakers – 175 watt each – 4 ohm each – Wired in series – Final impedance @ 8 ohm. I daisy these cabinets together – Speaker wire from amp to cabinet A… Read more »

Hi Aaron, In my opinion, if the overall volume is thunderous, then you are not under-powering the speakers. Sure, you are not driving them to their full potential, but they are obviously being powered sufficiently for your use. How the power is divided between the speakers is not too difficult to work out. Each cabinet is 8 ohms, so the each cabinet gets 50% of the amplifier power. Then each cabinet splits the power between each of its speakers evenly. So the in the 410, each speaker would 12.5% of the amplifier power. In your home made cabinet, each speaker… Read more »

Hiya Geoff, thanks so much for writing this article and helping all of us out. I have six eight ohm speakers and a Pyle Pro PCA3 stereo amp, with each amp rated at 75W at 4 Ohms. I’m planning on connecting three Boston CR55 speakers to each side. If I’ve synthesized this article correctly, in parallel I’d get an impedance of 2.66 ohms, and in series an impedance of 24 ohms. I’m assuming it’s a better idea to wire in series in this case, but I wanted to double-check. If my understanding is correct, having them wired in parallel would… Read more »

Hi Nico, Your calculations and assumption are correct. Three speakers wired in parallel would overload the amp when it is at full power. I also suggest it will be at full power most of the time – due to a market ploy. The 75 watts it is markets at is a absolute peak power per channel – probably only for a few seconds. When looking at the manual for the amp, it say the output with 10% distortion is 23 watts per channel. With 1% distortion it outputs 15 watts. I just picked searched for a Yamaha stereo amp and… Read more »

Geoff, Have a interesting configuration I am attempting to implement. I will be using a Sonos CONNECT:AMP that has 55W at 8 Ohms. I will be using it to be powering 2 zones, each with a Russound ALT-126R. I will be connecting the Amp to a Russound EZB-8, which I believe wires in parallel, then out to the VCs. One zone will be connected to a single pair of stereo speakers (8 Ohms). The second zone will be connected to 2 single point stereo speakers (8 Ohms), so the equivalent of two pairs of speakers. I am trying to figure… Read more »

Hi Josh, It seems you have a good handle on it all. In effect the 2nd zone will have a 4 ohm minimum load impedance. Therefore, on the VC for those speakers I suggest using the x4 setting. This will multiply the impedance by four, that is 16 ohms. For the VC feeding the 8 ohm speakers, set that to x2. This will also give a total of 16 ohms. Both 16 ohms in parallel will a total load impedance of 8 ohms when both VCs are on full. You can certainly use the EZB-8, but for two cables I… Read more »

Hi Geoff my question is I have 6 speakers 4 are 2 ohm per coil dual voice coil speakers and the other 2 are single voice coil 8 ohm is there a way to wire for a 1 or 2 ohm load or a 4 ohm load maybe I can’t find any calculators for different voice coils and impedance. Any help will be greatly appreciated. P.s. I’ll be hooking up to my 250w or 500w per channel 2 channel 1 ohm stable car amplifier in my car. Thank you so much.

Hi Jimmy, As I understand it, you will have 3 speakers for each amp (left and right). So for one amp there will be a 8 ohm speaker and two other speakers, each with two 2 ohm coils. The problem with not having the same impedance for each speaker is the power sharing. Each speaker will not get the same power, more about this shortly. If your connect the dual coils in series, that will give you 4 ohms for each of those speakers. Now you could simply run the two 4 ohm and one 8 ohm speaker all in… Read more »

Thank you Geoff that was very helpful and descriptive I appreciate that. I believe I am going with the second option so as to not put a strain too much on my amp. Your saying to have the coils for the 4 dvc 2ohm speakers wired in series then on each side of my amp have 2 of the dvc speakers and 1 of the svc 8ohm speakers wired in parallel together? I believe I read that properly.

Yes that’s correct Jimmy.

have fun with it

Geoff