How to Connect 4 Speakers to a 2 Channel Amp

An ideal PA system should have 4 speakers. This makes it easier to cover all four corners of the event center while you deliver quality sounds to your audience. If this is what you want to achieve, then you have come to the right place. The only challenge now is that you have a 2 channel amp, so how do you connect 4 speakers to a 2 channel amp? 

To connect 4 speakers to a 2 channel amp, you need to split the 4 speakers’ load equally between the 2 channels and then wire the speakers in a series or parallel connection. If you are using similarly rated speakers, you should wire 2 speakers at each of the amp’s channels. 

When it comes to amps and speakers, you should be careful not to overload the amp with so much power demands, otherwise, you will damage the components in your audio system. Since you want to connect 4 speakers to your amp, it is important to know which factors to consider, so keep reading this article as I guide you on how to connect the speakers to your amp safely. 

Can You Power 4 Passive Speakers With a 2 Channel Amp?

You can power any number of speakers with your amp provided that the amp has the capacity to do so. 

So, your 2 channel amp can power 4 speakers. The amp must have sufficient power to deliver to all 4 speakers in order for them to work. 

You should ensure that the power ratings of the amp and the 4 speakers are matched. It is easy to determine these power ratings. 

Just look at the back of your speakers and you will see the power ratings and impedance of the speakers written there. 

The power rating is measured in Watts and the impedance is measured in Ohms. 

Make sure that the overall impedance of your speaker system matches the specified impedance of the amp and you’ll be good to go. 

How to Balance Power for the 2 Channel Amp

The 2 channel amp obviously has 2 channels – the L channel and the R channel. 

When you want to connect 4 speakers to these channels, you should, first of all, calculate the total power of the speakers that you want to connect. 

For example, if you have 4 speakers which have a power rating of 25 Watts each, the sum of the speaker’s power will be 100 Watts. 

With a knowledge of the total power of your speakers, try to balance this power between the two channels. So, you should divide the 100 W by 2 to obtain 50 Watts. 

What this means is that at one channel you are going to connect speakers that will sum up to 50 Watts and then also connect speakers that have a total power rating of 50 Watts at the other channel. 

This also means that you will connect 2 speakers at the L channel and then connect 2 speakers at the R channel as well. 

Also Read:

How to connect 6 speakers to a 2-channel amp

Should I Connect the Speakers in Series or Parallel?

Now that you know which speakers to connect to at each channel, the next question you should answer is which configuration you are going to wire speakers. 

This boils down to whether you should a series connection or a parallel connection. In order to answer this question you should determine the total impedance of your speakers and cross-check from the amp’s spec sheet if the speakers’ impedance is within the specified range for that amp. 

Different speaker configurations will result in different impedance even though you are using the same speakers. 

So, if you want to wire your speakers in series, but realize that the total impedance of the speakers does not match the amp, you should consider wiring the speakers in parallel. This will result in a total speaker impedance that may match the specs of the amp. 

How to Calculate Total Impedance of Speakers

When it comes to the impedance of your speakers, you should be very careful about them. 

This is because you may end up damaging your amp and speakers or producing distorted sounds when you use speakers whose impedance does not match your amp’s specifications. 

For the speakers that you will be connecting to the channels, you should calculate their overall impedance as follows: 

• For a series connection, sum up all the impedance of speakers in order to get the overall speaker impedance.
• For a parallel connection, divide the sum of the speaker’s impedance by the product of all the impedance of the speakers. A quicker way of obtaining the overall impedance if you are using two speakers with the same impedance is to simply divide the impedance of one of the speakers by two.

For example, if you need to connect 2 8-Ohm speakers to the amp, wiring the speakers in series will produce 16 Ohms overall impedance while wiring the same speakers in parallel will produce 4 Ohms overall impedance. 

Once you calculate the total impedance of your speakers, cross-check from your amp’s spec sheet and find out if the total impedance that you got from the series calculation falls within the capacity of the amp. 

If it does, you can go ahead and use a series connection for your speakers. If it does not, use the impedance from the parallel connection and cross-check from the spec sheet if the impedance matches your amp’s requirements. 

Go ahead and connect the speakers in parallel if you get a match.

How Do I Connect 4 Speakers in a Series to a 2 Channel Amp?

The trick here is to concentrate on one amp’s channel at a time. You should connect 2 speakers in a series on one channel and then connect the other 2 speakers on the other channel, totaling 4 speakers in all. 

Here are the steps to connect the 4 speakers to the 2 channel amp: 

1. Identify the positive and negative terminals of the amp’s channel and the speakers. You should see the plus and minus signs written beside the ports.
2. Pick the first speaker and connect the positive terminal of the amp to the positive terminal of this speaker using speaker wires.
3. Connect the negative terminal of the first speaker to the positive terminal of the second speaker.
4. Connect the negative terminal of the amplifier to the negative terminal of the second speaker to close the circuit.
5. Move to the second channel and go through steps 2 to 4 to connect the other 2 speakers in series to the amp.

How Do I Connect 4 Speakers in Parallel to a 2 Channel Amp?

You also divide your speaker into two and connect 2 in parallel at the first channel while you connect the other 2 to the second channel. 

The process is not simple and you can follow the steps below to connect the speakers in parallel:  

1. Identify the positive and negative terminals of the amp and the 4 speakers.
2. Get the first speaker and wire the positive terminal of the amp to the positive terminal of this speaker.
3. Use speaker wires to connect the positive terminal of the first speaker to the positive terminal of the second speaker.
4. Complete the circuit by wiring the negative terminal of the amp to the negative terminal of the first speaker.
5. Connect the negative terminal of the first speaker to the negative terminal of the second speaker using another wire.
6. Move to the second channel on the amp and then go through steps 2 to 5 to connect the other 2 speakers in parallel to that channel.

How Many Speakers Can You Connect to a 2 Channel Amp?

Connecting 4 or 6 speakers to your 2 channel amp should be okay for your audio demands. 

You can however connect more speakers to the amp if it has the capacity to handle them. 

The bottom line is that the amp should be able to handle the impedance of the speakers and also match the speakers’ power ratings. 

If the power demands of the speakers exceed the capacity of the amp, your amp will most likely damage in no time. 

Conclusion

A 2 channel is a good choice for broadcasting music or audio at events and at your home. You can easily connect 4 speakers to it and this will allow you to cover a wider area rather than just using one it two speakers. 

Before you connect the speakers to the amp, you should consider the power ratings of the speaker and the impedance of the 4 speakers. 

The impedance of the speakers is what will guide you on whether to connect the speakers in series or parallel. 

If the impedance of your speakers is lower than the amp’s specification after you connect them in parallel, switch to a series connection and your speakers’ impedance will most likely match the specifications of the amp.