How To Connect A Powered Subwoofer To Passive Speakers

by Matthew David | Updated: 09/13/2023

How To Connect A Powered Subwoofer To Passive Speakers

Have you ever listened to a song with deep bass that you could feel in your chest? That’s the magic of a subwoofer. But did you know you can add that powerful bass experience to your existing speakers? In this guide, I’ll show you how to connect a powered subwoofer to passive speakers in a few easy steps.

Introduction

First, let’s clarify what passive and powered speakers are. Passive speakers require an external amplifier to power them, while powered speakers have a built-in amplifier. The key benefit of adding a powered subwoofer to passive speakers is to improve bass response.

According to audio expert Paul White, a good subwoofer can add “authority and depth” to music and movies. Who doesn’t want that?

In this guide, I’ll outline three simple methods to connect your new powered subwoofer using either an external amplifier, your existing amplifier’s line out, or an external crossover.

By the end, your audio will have that deep, rumbling bass that brings music to life. Let’s get started!

Equipment You’ll Need

To connect a powered subwoofer to passive speakers, you’ll need the following equipment:

The cables and ports you’ll use depend on the outputs and inputs of your specific equipment. We’ll go through the connection specifics next.

Method 1: Using an External Amplifier

The most straightforward way to add a powered subwoofer to an existing passive speaker setup is by using an external amplifier.

Here is a diagram showing how to make the connections:

[Diagram showing subwoofer connected to passive speakers via external amplifier]

Follow these steps to hook it up:

  1. Connect your passive speakers to the external amplifier using speaker wire. Match the positives and negatives.
  2. Connect the amplifier’s main outputs to your powered subwoofer’s inputs using RCA or XLR cables.
  3. Connect the high pass output jacks on the back of the subwoofer to the inputs on the external amplifier.
  4. On the subwoofer, set the crossover frequency that determines the divide between bass and mids/highs. Start around 80-100 Hz.
  5. Power everything on, play some music, and test out the new bass response! Adjust crossover frequency and volume levels as needed.

So what’s happening? The amplifier powers the passive speakers to handle mids and highs. The powered subwoofer gets the low frequencies and amplifies the bass via its built-in amplifier.

The crossover splits the signals so each element gets only the frequencies it needs. The external amp connects everything. Nice and easy!

Compared to the other methods, this gives you more flexibility and control over the signal flow. However, it does require an extra amplifier purchase if you don’t already have one.

Method 2: Using the Amplifier’s Line Out

If your existing amplifier for the passive speakers has line-level outputs, you can use those to feed signal to the powered subwoofer.

Here is how to make the connections:

[Diagram showing connections from amplifier line out to subwoofer]

Follow these steps:

  1. Connect your passive speakers to the integrated amplifier as usual.
  2. Connect your mixer’s main outs to the inputs on the amplifier.
  3. Locate the amplifier’s line outputs, often labeled “Line Out” or “Preamp Out.”
  4. Use XLR or RCA cables to connect the line outs to the inputs on the powered subwoofer.
  5. Power on the system, play some music, and adjust levels as needed.

Now the amplifier powers the passive speakers while also sending signal from its line outs to the subwoofer. This means you can add bass without extra amplification. However, your amplifier must have line-level outputs to use this method.

Method 3: Using an External Crossover

For maximum control over your audio signal, you can use an external crossover placed between the mixer and the amplifiers.

Here is how you would wire the connections:

[Diagram showing use of external crossover with sub and passive speakers]

Follow these steps:

  1. Connect the passive speakers to their amplifier as usual.
  2. Connect the mixer’s main outputs to the inputs of the external crossover.
  3. Connect the low frequency outputs on the crossover to the subwoofer.
  4. Connect the high pass outputs to the power amp driving the passive speakers.
  5. Set the crossover frequency on the external unit. Start around 80-120 Hz.
  6. Power up the system and test it! Adjust volume and crossover frequency until you like what you hear.

The external crossover network handles splitting the signals, sending lows to the sub and mids/highs to the speakers. This gives you maximum flexibility but requires purchasing an additional component.

Optimization Tips

To get the best performance from your new two-speaker plus sub system, follow these tips:

Troubleshooting Common Issues

If you run into problems getting your new system up and running, try these tips:

No output from speakers:

Excessive hum or noise:

Poor bass response:

FAQ

Do I need a separate amp just for the passive speakers?

Yes, passive speakers require an external amplifier to power them, while the powered subwoofer has its own built-in amplification.

What cables should I use to connect the components?

For best quality, use balanced XLR or TRS cables between the mixer/amp and the powered subwoofer. Speaker wire works well for connecting passive speakers to an external amp.

Where is the optimal position for the subwoofer?

Try placing the subwoofer near a wall or corner to amplify bass response. Away from walls in the middle of a room tends to be the worst position.

How do I properly set the crossover frequency?

Start around 80-120 Hz, then adjust higher or lower while listening to music to find the best blend between the sub and speakers.

What are some of the best subwoofer brands?

Top options are SVS, Rhythmik Audio, HSU Research, Monoprice Monolith, and Rythmik. Look for at least 300 watts power.

Conclusion

Adding a powered subwoofer to an existing passive speaker system is an easy way to improve bass response and make your audio really rock.

With just a few affordable components like an amplifier or crossover and the right cables, you can be bumping the bass in no time. Experiment with crossover settings and positioning to get that perfect heart-thumping low end.

For large or complex installs, it never hurts to have a professional handle the design and setup. But for most home or small business systems, you can definitely DIY it successfully.

I hope this guide has shown you how easy it is to add deep, powerful bass to any music or movies by connecting a powered subwoofer to passive speakers. Now get ready to feel the beat!