Can You Connect Active Subwoofer to an Amplifier?

Every subwoofer needs an amplifier to power its driver and an amplifier needs to be powered by electrical energy.

Subwoofers are specialized speakers typically meant to reproduce bass effects and are further categorized into two types: active and passive.

Active subs are also referred to as powered subs because they have a built-in amplifier in the enclosures.

On the other hand, passive subs are called passive because they depend on an external amplifier or a receiver to power their driver.

In this article, we will understand where and how you can connect an active subwoofer.

Can you connect an active subwoofer to an amplifier?

It is not recommended to connect an active subwoofer to an external amplifier or AV receiver if your intention is to power its driver.

These units are designed to receive line-level signals directly from a source device or preamp which includes a home theater receiver or an audio interface, etc,.

Simply put, you can connect active subs to compatible audio sources or simply use the subwoofer output port from a receiver or preamp dedicated to outputting low-frequencies.

In addition, you can connect a powered sub using RCA cables or proper speaker wires to an external amplifier for data transmission only and plug its power cable into the electrical outlet.

Active subwoofers are referred to as powered subwoofers because they already include an amplifier enclosed in the box to power the driver.

Additionally, the built-in amps are designed to automatically tune with the lower frequencies and deliver precise bass notes.

It simply means that the built-in amps in active subs have sufficient power to manage the driver’s power handling capacity.

Hence, connecting a powered or active subwoofer to an external amplifier may cause damage to its built-in amp, driver, or even the external amplifier.

How do you connect active subwoofers to external amps?

Active subwoofers are typically connected to their dedicated ports on an amplifier or receivers such as pre-out for subs.

There may be situations or specific preferences to use an external amplifier with a powered subwoofer.

In such instances make sure the units are compatible with each other before following the proper connection methods.

Here a few tips to connect active subs to external amplifier:

Considering the available ports on your active sub

  • Check if your subwoofer includes speaker-level inputs or line-level inputs such as RCA or XLR.
  • Most active subwoofers include both line-level and speaker-level inputs, it is provided by the manufacturers to offer more flexibility for different audio setups.

Determining the amplifier’s output capabilities

  • Ensure that the amplifier has a dedicated output for the subwoofer. You can also use a full-range speaker output with a crossover.

Connecting the powered subwoofer to the amplifier

  • If your active subwoofer has line-level inputs, use suitable cables for connectivity such as RCA or XLR cables.
  • You can connect the subwoofer’s input to the amplifier’s sub-out port or to the dedicated line-level output.
  • If the sub has speaker-level inputs only, then start by connecting the amplifier’s speaker output to the subwoofer’s speaker-level inputs (You will need suitable speaker wires).

Configuring the crossover and settings

  • For the active subwoofer, you should always set the crossover frequency according to the specifications defined by the manufacturer.
  • To optimize the integration of the subwoofer with the main speakers you can make necessary adjustments to the amplifier settings.
  • However, some amps may not include additional settings dedicated to some of the output ports.

Can you connect the surround speakers with an active subwoofer’s amplifier?

In most home theater systems, the powered subwoofers come in a package with small speakers to connect with.

So home theaters that come with small speaker unit, separate surround speakers that aren’t part of the sound system may not function with the active subwoofer’s amplifier.

The built-in amplifiers in powered subwoofer models are particularly designed and tuned to amplify low-frequency audio signals to produce bass.

If your home theatre system doesn’t include surround speakers, then ultimately it may not be featured to handle mid to high-frequency sounds.

Thus, connecting surround speakers to the amp of the powered sub would not support or deliver the full range of sound you desire from the additional speakers.

Additionally, most active subwoofers typically have line-level inputs or RCA inputs that are ideal for low-frequency signals only.

Hence, the lack of necessary outputs such as speaker-level outputs required for surround speakers makes them not suitable in most cases.

Finally, there can be a mismatch in the power requirements of the external surround speakers and subwoofers.

The amplifier in the active subwoofer may overpower or lack supplying enough power to surround speakers.

Remember, overpowering and underpowering the connected units can lead to poor sound quality or cause severe damage.

Can you run a subwoofer without an amplifier?

If you have a powered unit that is an active subwoofer you don’t need to connect it to an external amplifier because these units have integrated amps.

However, if you have a passive subwoofer then it will definitely need an amplifier to power its driver or else it won’t work.

Moreover, the amplifier needs to match the power requirements of your subwoofer unit. Too much or too little power will have a negative impact on the audio quality and can also cause damage to the unit and the amp.

Some like to have passive subs so that they can customize their audio systems as per their music-listening habits.

On the other hand, most people now prefer using active subs to minimize the setup requirements, save space, and eliminate the need to buy expensive amplifiers.

Final Thoughts

Connecting active subwoofers to external or additional amplifiers may not always deliver optimal results because these powered units are already capable of functioning with their built-in amplifier.

However, under specific conditions i.e., if there is any limitations in your audio setup, you can cautiously explore this particular connection type.

It is equally important to use proper cables and the right ports available on the amplifier with the subwoofer for connectivity.

Frequently Asked Questions

Can you connect multiple Active Subs to a Sound System?

If your receiver or audio source has multiple subwoofer outputs you can simply integrate more than one subwoofer to your sound system. Most modern units offer multiple connectivity to subwoofers to enhance the bass response.

Can you enhance the Bass Output in an Active Subwoofer?

You will need to make some adjustments to the crossover frequency setting so that the subs are integrated seamlessly with the main speakers. Additionally, you can align the subwoofer’s output with the main speakers using the phase control setting, and for optimal acoustics, you can consider room treatments such as bass traps.

Armed with a Diploma in electrical engineering and a remarkable 12 years of expertise, he excels in rejuvenating music systems, washing machines, dryers, and laundry-related appliances. Manish's profound insights and practical know-how establish him as a credible authority in appliance and music system repairs. Contact: manish.singh (at) He's always ready to lend a helping hand!