Skip to Content

2 Ways To Wire A 4-Channel Amp To 6 Speakers (2022 How-To)

How To Wire A Channel Amp To 6 Speakers

Do you want to step up the audio experience in your car?

Getting an amplifier is always a good idea.

Wiring speakers to that amplifier is even better.

But let’s say you have a 4-channel amplifier.

How many speakers can you wire to that?

And can you wire more than 4 speakers at once?

In fact, is it possible to wire a 4-channel amp to 6 speakers?

Spoiler alert: YES.

Read on to find out:

  • If you’ll get great sound quality out of the process.
  • How you can wire 6 speakers to a 4-channel amp.
  • Whether wiring 6 speakers to a 4-channel amp is safe.
  • What impedance means and how it affects your amp and speakers.
  • And so much more…

Can I wire a 4-channel amp to 6 speakers?

Yes, you can wire 6 speakers to a 4-channel amp. You can do this in two ways: in series or in parallel. But remember, wiring 6 speakers to a 4-channel amp is not considered good practice. For best results, you should wire 6 speakers to a 6-channel amp. 


How to wire a 4-channel amp to 6 speakers? 2 ways


#1: In series

Before we get into it, let’s first discuss basic concepts about amplifiers and speakers.

So what is an amplifier, you ask?

An amplifier is a device that amplifies or increases any audio input.

So in simpler terms, an amplifier takes sound and boosts it so that you can enjoy audio inside your car.

You’re not the first person to want to connect an amp to speakers in your car.

There are so many others who do the same.

So many, in fact, that the car amp market is expected to gain more than $650M in profit by 2025.

Now, how does that relate to your speakers?

When you connect an amp to speakers, the amp boosts the sound from the head unit so that it can blast out of the speakers.

Many in-dash car stereos use only about 15 to 18 watts, which isn’t enough for a nice sound experience.

If you’re using extra speakers, like 6 speakers, your amp will handle all that power.

So now let’s go back to the matter at hand?

“Great! How do I connect a 4-channel amp to 6 speakers, then?”

You can wire your 6 speakers to your amp in a series.

“How does that work?”

When you connect speakers in a series, you connect them to each other in a line.

You take the positive end of 1 speaker, and then connect it to the negative end of another 1.

You do this until all the speakers are linked.

“Is connecting via series safe?”

Very much so.

Connecting in a series evenly distributes the power throughout the entire connection.

How is that? This is through something called impedance.

“What is impedance?”

In simple terms, impedance measures how much a device opposes or resists the flow of current.

Think of it like this: your speaker is a pipe, music is the current, and your amp is the pump.

The bigger the pipe is, the easier the current will flow.

Also, if there is nothing inside the pipe that restricts the flow, the easier the current will flow.

Impedance is what restricts the flow; the lower the impedance, the more powerful the flow.

And that is very important to the safety of wiring speakers in a series.

Let’s say each speaker has an impedance of 4 Ohms.

Connecting two speakers to the head unit will give you an impedance of 8 Ohms.

And the higher the impedance, the less power your amp will use.

“Sounds exciting! How do I do that?”

So what happens is you connect 2 speakers to 1 channel in your amp.

The other 2 speakers will then be connected to another channel.

And the remaining 2 will each be connected to 1 channel.

Follow these step-by-step instructions to connect in a series.
Series Circuit

Step 1: Connect the negative end of Speaker #1 to the negative terminal on Channel #1.

Step 2: Connect the positive end of Speaker #1 to the negative end of Speaker #2.

Step 3: Connect the positive end of Speaker #2 to the positive terminal of Channel #1.

Step 4: Connect the negative end of Speaker #3 to the negative terminal of Channel #2.

Step 5: Connect the positive end of Speaker #3 to the negative end of Speaker #4.

Step 6: Connect the positive end of Speaker #4 to the positive terminal of Channel #2.

Step 7: Connect Speaker #5 to Channel #3.

Step 8: Connect Speaker #6 to Channel #4.

This type of connection has a lot of advantages, such as:

  • It’s relatively safe.
  • You can easily swap out speakers if you want to replace them.
  • You don’t need to buy more equipment to connect all 6 speakers to a 4-channel amp.

But it also has disadvantages. These are:

  • Higher impedance means less power.
  • With less power, your amp will produce lower sound quality.

Watch how you can safely connect speaker wires to your amp here:

#2: In parallel

“But I don’t want to lower sound quality!”

We get that.

This is why the second type of connection may be better for you.

Aside from wiring in series, you can connect 6 speakers to a 4-channel amp by wiring in parallel.

How does that work, you ask?

When you wire in parallel, you use various wires to connect different speakers.

When wiring in series, you connect speakers using a sort of line, right?

When you wire in parallel, you connect all the positive terminals together, and the negative ones, too.

You do this until all 6 speakers are connected to your 4-channel amp.

“Is wiring in parallel great for sound quality?”

Definitely!

This is where impedance comes in again.

Remember, the higher the impedance, the lower the power of the amp.

And the opposite also applies: the lower the impedance, the more power the amp uses.

So let’s suppose you’re connecting 4 speakers to the head unit.

If the impedance of these 4 speakers is 8 ohms, connecting in parallel will divide the impedance between the number of speakers.

So that becomes 2 ohms.

Low impedance, high power.

You’ll have fun blasting your music and enjoying great clarity.

“Amazing! So how does it work?”

To connect 6 speakers to a 4-channel amp in parallel, you start by connecting 2 speakers to 1 channel.

The other 2 will be connected to another channel.

And the remaining 2 will each be connected to a channel.

So that’s a total of 6 speakers and 4 channels.

In the real world, the process is even easier to practice.

This is why connecting in parallel is the preferred method of most people.

It’s fundamentally sound, and it works without a hitch.

Follow these step-by-step instructions to connect in parallel.

Step 1: Connect the negative end of Speaker #1 to the negative terminal of Channel #1.

Step 2: Connect the negative end of Speaker #1 to the negative end of Speaker #2.

Step 3: Connect the positive end of Speaker #1 to the positive terminal of Channel #1.

Step 4: Connect the positive end of Speaker #1 to the positive end of Speaker #2.

Step 5: Connect the negative end of Speaker #3 to the negative terminal of Channel #2.

Step 6: Connect the negative end of Speaker #3 to the negative end of Speaker #4.

Step 7: Connect the positive end of Speaker #4 to the positive terminal of Channel #2.

Step 8: Connect the positive end of Speaker #3 to the positive end of Speaker #4.

Step 9: Connect Speaker #5 to Channel #3.

Step 10: Connect Speaker #6 to Channel #4.

Connecting in parallel has a lot of advantages, such as:

  • It’s easier than connecting in series.
  • You get great sound clarity and quality.
  • Even if one speaker fails, your entire unit will still function.

But it also has a few disadvantages, like:

  • You can’t always play music at a high volume.
  • It’s not as safe as connecting speakers in series.
  • The connection will generate a lot of heat, which can damage your amplifier.

You may also like: 3 Ways to Wire 4 Speakers to a 2-Channel Amp Diagram

How many speakers can a 4 channel amp handle?

A 4-channel amplifier can handle as many as 8 speakers.

The question is: should you?

The answer depends on whether you can:

  • Ensure the longevity of your unit.
  • Safely connect your speakers to your amp.
  • Compromise between performance and equipment safety.

You see, using 6 speakers for a 4-channel amp is not good practice.

“Why? What is good practice?”

The best thing to do with a 4-channel amplifier is to connect 4 speakers to it.

Or 2 speakers and a subwoofer.

“So let’s say I have 4 speakers. How do I connect them to my 4-channel amp?”

There are three ways to do this:

  1. Connect the speaker outputs to the amp’s inputs.
  2. Connect a line-level adapter to your radio; aftert this, use RCA cables to connect to the amp.
  3. With RCA cables, connect your radio to your amp directly.

If you want to get the best results from a 6-speaker setup, you should get a 6-channel amp.

But if you’re serious about using your 4-channel amp to connect your 6 speakers, you will need the following: