Wiring speakers to set up a music system or a surround sound system needs a little more effort than simply following instructions. You might have heard of series wiring and parallel wiring or a combination of both. Connecting the speakers needs a little more work. Nevertheless, we’ll tell you everything about parallel vs series speaker wiring here.
How you wire the speakers will decide the output quality. Some say series wiring is the best while others swear you should opt only for parallel wiring. Then others recommend series/ parallel combinations to get the best of both.
Yes, we know it’s confusing. To know how to wire speakers, you’ll need to know about load impedance, phase, and, most importantly, ohms law. In this post, we’ll learn about the working of a speaker and see how series wiring is different from parallel wiring. Let’s get started.
What is Inside a Speaker?
Do you know how the inside of a speaker looks like? If you’re planning to buy one of the best surround sound systems you need to know this. A speaker is a simple yet effective device that produces sound. But it doesn’t work on its own. The speaker needs to be connected to a stereo or an amplifier to play the audio. You can easily connect more than one speaker to the receiver.
You’ll find a voice coil, magnet, and speaker cone inside a speaker. One receives the electric signals and creates a magnetic field. The other produces sound waves, converting electric signals to audio and playing it out loud. The cone has to move thousands of times per second to play the audible and understood music by humans. That’s because the music is measured in the kilohertz range.
Let’s take a quick look at the different components of a speaker:
How Does a Speaker Work?
Let’s connect speakers to the amplifier. Whether you choose two speakers, four speakers, or multiple speakers is your choice.
The amplifier sends electric signals, alternating between positive and negative, to the speakers. This is in the musical waveform. The electric current goes through the voice coil located inside the speaker. It first goes from the positive side to the negative side.
This creates a magnetic field that moves towards and away from the coil alternatively as the electric charge changes between positive and negative. First, the magnetic field is in the same charge as the magnet. This causes the field to move away from the magnet, causing the speaker cone to move forward, pushing the air, and creating sound in the process.
Here, we need to remember that the speaker uses AC (alternating current). This means the electric signal will reach the peak before it’ll continue downwards and reverses direction. As the electric signal continues downwards, the magnetic field will weaken, allowing the speaker cone to get back to its original position.
The zero voltage point is known as zero crossovers, where the speaker cone back in its place. The electric signal now reverses direction by changing the polarity to negative. This changes the direction of the current in the voice coil (it goes from the negative side to the positive).
Now, the magnetic field is in the opposite charge, thus attracting the magnet. The cone moves again but this time from front to rear (in the reverse direction). Then, as the sine wave on the negative side starts to weaken, the speaker cone will get back to its original position.
This front-original-back-original movement of the speaker cone happens thousands of times every second to produce sound audible to human ears.
Single Speaker Wiring
In the parallel vs series speaker comparison, let’s discuss single speaker wiring first. However, before we see how a single speaker is wired, let’s know a little more about speaker impedance, resistance, and loading.
Speaker impedance is an ohms rating that indicates variation in the frequency of the input signal. You’ll find this listed in the speaker specifications. Speakers have ohms ratings in variables of 4 (4 ohms, 8 ohms, and 16 ohms).
Some have alternating ohms ratings, resulting in more flexibility to match the overall equivalent impedance of the speaker to that of the amplifier. This factor plays a vital role when you connect multiple speakers to the amplifier. It also changes based on whether you choose series wiring or parallel wiring.
Single speaker wiring is the easiest of all. You just need to connect the positive side to positive and the negative to negative from the amplifier to the speaker. You need to match the amp and ohm of the amplifier to that of the speaker.
For example, if you choose a 50 W 8-ohm amplifier and connect it to a speaker with the same specifications, the overall output will be 8 ohms.
This is a single speaker wiring arrangement:
Multiple Speakers in Series Wiring
What if you’ve got to connect multiple speakers to the amplifier using series wiring? One thing you need to keep in mind is the total impedance of speakers should equal the output impedance of the amplifier.
If we take an 8-ohm amplifier, you’ll need two 4 ohm speakers (with 25 W each) connected in series to match it. If you have a 16-ohm amplifier, you’ll need two 8 ohm speakers or four 4 ohm speakers to match the amplifier. You can even set up eight 2 ohm speakers.
Let’s see how you can connect speakers to the amplifier using series wiring.
The positive of the amplifier goes to the positive of the first speaker, and the negative goes to the negative of the last speaker. The speakers are connected, from the first to second to third, and so on, until all the speakers are connected.
If you want to increase the overall or equivalent resistance of the speakers, a series connection is the best option. Series circuit is known as the voltage divider as each speaker gets a percentage of the total power.
A simple way to calculate series wiring is by using this:
Znet = Z1+Z2+Z3+Z4+…
Wiring speakers in parallel is easy when you connect two speakers or more to the amplifier. However, here you need to understand that the overall impedance of the speakers is halved instead of being added.
For example, you need to connect two 16 ohm load speakers to an 8-ohm load amplifier if you use the parallel connection.
So how do you wire multiple speakers in parallel?
You’ll need more wires here. The positive of the amplifier will be connected to the positive of both speakers. The same is followed for negative. The speakers are not connected but are fully connected to the amplifier.
When you add other speakers to the circuit, the overall resistance drops, which means the current must increase (according to ohms law). As you bring speakers to the parallel circuit, the current draw on the amp increases accordingly.
Here’s the formula for calculation:
Znet = 1 / (1/z1+ 1/z2+ 1/z3+ /z4+…)
A Combination of Two Speaker- One Series and One Parallel
A combination of series-parallel wiring is nothing more than two sets of speakers with series wiring that are connected to the amplifier using parallel wiring. The main reason to use combination wiring is to distribute the load and resistance evenly through the speaker network. However, you do need to get the configuration correctly. You should calculate the loads to ensure that the wiring doesn’t lower the resistance too much.
Look at the below example to learn the combination speaker wiring. We’ll take four 8 ohms speakers and connect them in series/parallel wiring to match the 8-ohm load of the amplifier. Arrange speakers A, B, C, and D in two lines (A, B in the first and C, D in the second).
- Positive of A is connected to the positive of C.
- The negative of A is connected to the positive of B.
- Negative of B is connected to negative of D.
- Positive of D is connected to negative of C.
The amplifier’s positive side is connected to the positives of A and C, and the negative is connected to the negatives of B and D.
The left speakers together are connected in parallel to the amplifier and so, are the right speakers. The top speakers are connected in series wiring similar to the bottom speakers. This combination speaker wiring will result in an 8-ohm output impedance.
You can match the output impedance using series or parallel connection box. That said, a bit of mismatch is good for the sound quality. This happens when you have to use more than one speaker cabinet. If you have one each of 8 ohm and 16-ohm speaker cabinets, you can safely plug them into 4 ohms and 8-ohm amplifiers. It means the speaker impedance can be double the amplifier ohm but not more.
So, after understanding parallel vs series speaker wiring, what do you think? Should it be series or parallel wiring? Parallel wiring is preferred as the sound output is louder due to lower resistance. The speaker output from series wiring has high mids with more animation and chime. Deep bass sounds wonderful through speakers connected in parallel. A combination wiring should do the trick of producing a fuller sound.
We hope you found our post on parallel vs series speaker wiring worth reading. If you have any questions, please feel free to drop them in the comment section below.