Guide Speakers

Subwoofers: The What? The How? and Yes, The Who? Guide 2023

Written by Edwards

what is a subwoofer

If you are wondering, “what is a subwoofer?” We are about to educate you. A subwoofer is a type of speaker that’s fundamentally designed to produce bass, which is the lowest frequency sound.

Subwoofers are larger than normal speakers and can be installed in vehicles or at home. These speakers are so powerful and thunderous that when turned on, they shake up the entire vehicle and windows if you are at home.

For powered car subwoofers, you don’t need to install a car amplifier as these types of subwoofers come with internal amplifiers.

However, you need to install a good quality car battery to get an immersive sound experience, like the one you experience in movie theatres as subs take up a lot of battery juice.

A home subwoofer is sometimes called an LFE (low-frequency effects) speaker in a home theater system. These systems come in many forms, there’s a 5.1 system, a 7.1 system and so on.

The “.1” channel always represents subwoofer, while the “5” or”7” represent the number of surround speaker channels in the home theater system.

If you' re living in an apartment, you might want to apply for a noise permit or time when your neighbors are not around to blast your music through your subwoofer.

The same case applies if you are driving through a gated community. You might want to lower the volume on your Stereo HEAD UNITS if you want to avoid a noise complaint from the residents.

Types of Subwoofers

There are two main types of subwoofers; powered and passive subwoofers. Let’s look at them below in detail:

  • 1. Powered SubwoofersYou can describe powered subwoofers as complete subwoofer speakers. This is because they powered by an internal amplifier which is installed alongside the subwoofer speaker in the subwoofer box.
  • All powered subwoofers need an AC power input to operate. They also need a line output such as a pre-out, LFE-out or sub-out to take out some of the power load from the amplifier or receiver and redistribute the power to the tweeters and mid-range speakers.
  • Most home theater subwoofers are powered subwoofers this is because they have an internal amplifier and use an AC power output to work.
  • Most boat and marine subwoofers are also classified as powered subwoofers despite drawing power from a DC source.
  • The same applies to powered subwoofers for vehicles, which use a power converter to convert the DC power from the car’s battery to AC power.
  • 2. Passive SubwoofersPassive subwoofers are powered by an external subwoofer to produce and sustain their thunderous bass output. Keep in mind that some passive subwoofers cannot work without an external amplifier while others work but produce poor-quality sound.
  • The low-frequency sounds produced by subwoofers need a lot of power. As such an amplifier or receiver needs to be installed to “amplify” the power to sustain the low- frequency bass.
  • It goes without saying that the most powerful subwoofers require the most powerful amplifiers to work well. Most shallow mount subwoofers such as under seat subwoofers are passive subs.
  • This is because most of them don’t have space to accommodate an internal amplifier in the sub box.
  • Also, most passive subwoofers come as the speaker piece alone and as such you need to hire a professional to mount it into a box.
  • You can also choose to build a subwoofer box for yourself and even integrate two subwoofers into the box while you are at it if you want to intensify your sound experience.

Subwoofer Sizes

Ladies and gentlemen, when it comes to subwoofers, size, really does matter. In this section, we will review the most common subwoofer sizes from the different subwoofer brands such as Alpine, Sony, Pioneer, Kenwood and more.

  • 1. 8-inch subwooferThese are the smallest subwoofers and you can find them in some vehicles with the stock audio system. They produce a punchy bass sound that adds a bit flavor to a vehicle’s music experience.
  • Vehicle manufacturers especially like these subwoofers as they are compact, lightweight and inexpensive to install.
  • 2. 10-inch subwooferMuch like the 8-inch subs, the 10-inch subs are also compact, lightweight and inexpensive. They are slightly more powerful and produce more rumble than 8-inch subs. These speakers are more common in small and mid-sized vehicles.
  • 3. 12-inch subwooferIf you ask most car audio professionals, they will tell you that the 12-inch subs are the best car subwoofers. These speakers are not common vehicles’ stock audio systems as they are both larger and heavier than the aforementioned subs.
  • You can never go wrong with 12-inch subs if you’re planning to upgrade your car’s stock audio system.
  • These speakers produce the correct amount of loudness and accuracy. If you are after the perfect blend between base and clarity, the 12-inch subs are the ones to go for.
  • 4. 15-inch subwoofer15-inch subs are by far the largest and most powerful subs. They are designed to produce the lowest bass frequencies of all the subs. 15-inch subs sacrifice the clarity of 12-inch subs to produce even more bass.
  • If you are a bass head, you will appreciate these speakers as their thunderous bass eclipses the rumble of 8-inch and 10-inch subs as well as the deep bass of 12-inch subs.
  • These speakers are enjoyed best when playing instrumental-based music such as dubstep, techno, electronic music, and more.
  • Due to their monstrous size, 15-inch subs can only be installed in the trunk, which makes them perfect for tailgating. You will have the loudest car in the yard when you turn on the sub and the thunderous bass from your sub will cause some tremors.

How Do They Work?

  • How do subwoofers work and why do they require a box? Well, subwoofers are designed to produce the lowest-frequency sounds, and that is usually between 20 and 80 Hz octaves.
  • This means they need to be enclosed in a specially constructed box to trap the vibrations and produce good bass. Have you ever wondered why all home and car music systems only have one subwoofer and multiple speakers?
  • This is down to the fact that subwoofers produce sound frequencies that range between 20 and 80 Hz. The human ear can hear low-frequency sounds of 20 Hz but cannot tell the source of the sound if the sound waves are vibrating below 100 HZ.
  • Therefore, having 2 or more subwoofers will disorient your hearing sense making it intolerable. Sound experts install two or more subs in the same subwoofer box to avoid this problem.
  • Subwoofers incorporate the following features to optimize their bass output:
  • I. Subwoofers have a bass reflex design that uses the ports in the sub box to force out more air to increase the bass response
    II. Some subwoofers use passive radiators instead of ports to increase sound precision and efficiency.
    III. Crossovers direct all low-frequency sounds (usually between 80 and 100 Hz) from the source to the subwoofer.
    IV. Subwoofers use a directionality feature so that listeners can tell the source of the sound.
    V. Front and down-firing feature help the sub radiate the sound in all directions for maximum impact.

Who Needs a Subwoofer?

  • 1. Owners of Old Music SystemsLet’s face it, old music systems for homes were and continue to be reliable as ever. It’s not just with music systems but the quality of products that are being produced nowadays has deteriorated.
  • However, despite all their reliability, old music systems don’t just cut it when it comes to producing deep, satisfying bass.
  • Most of these old music systems were sufficient back in the day but with the advancement of technology, you will find that a 10-inch subwoofer of today is more powerful than a 10-inch sub of 10-years ago.
  • 2. Those Who Love To Play Loud MusicNormal speakers are good on their own when you’re playing music at a reasonable level. The problem comes in when you play music at a high volume level. The sound comes out distorted and is unpleasant to listen to.
  • Subwoofers sort this problem. They allow you to play loud music with deep base and with perfect sound clarity.
  • You will greatly enjoy loud music from a subwoofer and you’ll get the benefit of feeling that subwoofer rumble.
  • 3. Those Who Want To Immerse Themselves in The SoundThere’s no denying that subwoofers add emotion and soul to sound. So whether you are listening to music or watching a movie, the bass created by your subwoofer will make you feel like you are in the movie or the music.
  • Normal speakers are just ok, but sadly they cannot transcend you to a place where you feel the emotion of sound.
  • If you want proof of the aforementioned statement, try out this simple experiment. Put on a film on a television and watch it with your eyes closed using the sound from your television set. Now, repeat using sound from a subwoofer-surround system.
  • How do the two experiences compare? Do you feel more immersed in the film with the sound from the television set or the subwoofer-surround system?

Installation Tips for Subwoofers

  • There are many places to place you can place a subwoofer in a room but the front of the room is the best place for placing a subwoofer. This is because the sound coming from the front of a room sounds more pure and clearer than other positions.
  • Also, placing the sub on the sides or at the back of the room will make it more complicated to wire a subwoofer if you are using a wired system.
  • You will need to buy longer cables and go through the hassle of hugging the wires to the wall If you are planning to install a subwoofer in your vehicle, there are two main places you can do this.
  • The first and most common place is the trunk of your vehicle and the second place is underneath the front seats. The trunk of the vehicle is the preferred installation place as it provides more space to fit subwoofer boxes of all sizes and shapes.
  • Other people prefer to install their subwoofer underneath the front seats as the bass sounds purer due to its close proximity. But keep in mind that the space underneath the seats is limited and can only accommodate small-sized subs.
  • You can read more on What Speakers Can Fit My Car,  how to install car speakers and look at some of the best cars speakers from our other guide.


  1. Electronic House, Importance of Subwoofers in Your Home Audio System, serves discriminating consumers who enjoy the elegance, simplicity, and fun afforded by integrated home technology
  2. lifewire, All about Subwoofers, Bass Shakers, and Tactile Transducers, teaches you how to best use your screens and gadgets, have fun with technology
  3. cnet, Who needs a subwoofer?, Read the latest technology news and unbiased product reviews
  4. eBay, Woofer vs. Subwoofer: Is There Really a Difference?, multinational e-commerce corporation.

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