Skip to Content

Do In-Ceiling Speakers Need a Backbox? Are Backboxes Necessary?

When installing my home theater, one of the things I considered was speaker placement. Did I want a bunch of external units placed throughout my home theater? Alternatively, did I want the sleek look of built-in speakers? As I researched this, I discovered that many built-in speakers get a bad rap. However, after looking further into this, I discovered the likely source of the issue in sound quality stemmed from one simple factor: whether a back box was installed or not.

So do in-ceiling speakers need a backbox? Yes. Failure to install a back box for your in-ceiling speakers will dilute the sound quality and lead to noise pollution in other areas of your home.

In fact, in many cases, the backbox was the difference between a sound investment and a wasted one, additionally, other users wonder if in-ceiling speakers also need power, a topic we explained in our other article.

Below, I explain why the backbox is important if you want to install in-wall or in-ceiling speakers. I also walk you through an easy method for creating your own speaker backbox without breaking the bank.

What Is A Speaker BackBox?

A back box is a device used to capture and redirect the sound waves emanating from your in-ceiling/in-wall speaker. These devices can be built out of many different materials, including plastic and wood. The right backbox protects your speaker and provides reliable support.

In-ceiling speakers are typically designed to relay sound into a room without being aesthetically intrusive. The majority of these speakers, however, come without a backbox.

What this often means is that in-ceiling speakers leave you with less than desirable sound quality. By including a backbox, you can actually boost the sound quality. The backbox acts as an acoustic dampener and soundproofing object, preventing sound from escaping through the ceiling into the space above it. If you have a second floor, this can ensure your late-night Netflix binges do not interrupt the sleeping child in the room above you! Backboxes also help to redistribute those sound waves to listeners below, amplifying and improving sound quality.

A properly designed and built backbox will also keep your speaker well protected and mounted in your ceiling. They also help to obscure wires and give your home theater a neat, minimalist look.

When Should You Use a Speaker Backbox?

A backbox should be used any time you install a speaker in your ceiling or wall. The benefits of these devices outweigh all reasons not to include them. Based on soundproofing, audio improvements, and speaker protection – back boxes are vital to the overall value of your built-in speaker investments.

There are hundreds of speaker options available for home theater use. For many, hanging speakers around a room takes up more room than desired. As we’ve explained before, that is where in-ceiling or in-wall speakers come in. However, these speakers tend to have a bad reputation. Much of this is based on the lack of a backbox or the lack of a quality one. 

I went over the benefits of the speaker backbox above. But what does this actually mean to you? If you are like most homes in America, your family room is in the basement or on the main floor of your house. When you install built-in speakers without a backbox, the sound can penetrate walls and ceilings. This means, if your child’s bedroom is above the living room, you have to continually monitor and adjust the sound levels throughout the night to prevent them from waking your kid up while binge-watching the latest program on Netflix.

Vibrations can also cause dust particles to come loose behind your speaker. Amid the many other things that you can do to protect your speakers (our tutorial), a backbox helps to protect your speakers from dust that can decrease sound quality over time. They also securely support your built-in speakers and prevent them from falling out of your ceiling or wall once mounted. This protects your investment for years to come.

Easy DIY Method for Building a Speaker BackBox

Many of the metal or plastic back boxes available for purchase today are cheap and flimsy. The do-it-yourself (DIY) approach offers a custom option that often proves to be a better investment.

Step 1: Measure Your Speaker Dimensions

Determining your speakers’ dimensions is the first step towards building your backbox. Measure not only the diameter of the speakers’ face but also the depth of it.

Step 2: Cut Sides from a 2×4

Taking your measurements, cut 2×4 pieces to match dimensions needed for all four sides of your backbox. Most residential wall cavities will only allow for a 3-inch depth. However, a ceiling will allow you to use the full 4-inch depth of the 2×4. It is important to keep this in mind, as you may need to make an additional cut before assembling if you want your box to fit.

Step 3: Build Your Frame

After cutting your frame pieces from the 2×4, fasten them together using a nail gun or screws. Make sure your frame fits into place before proceeding.

Step 4: Measure and Cut Your Back Plate.

Trace the shape of your frame onto a piece of MDF or OSB. Using a table saw, carefully cut along these lines. This forms the rear plate for your backbox. Affix this piece to your frame with a nail gun or screws.

Step 5: Increased Soundproofing (Optional)

If you want to make your backbox more soundproof, you will need to invest in thinner MDF or OSB, as well as a damping compound. (Green Glue Noiseproofing Compound comes highly recommended by audiophiles who build their own systems!)

As with the backplate in step 4, you need to trace your frame dimensions onto two thin pieces of MDF or OSB. Before attaching these pieces to your frame, spread a layer of the damping compound between the pieces. This will help ensure your speakers are even less likely to transmit sound through walls or ceilings into surrounding rooms.

You should note that this step replaces step 4, if you opt to do it.

Step 6: Drill Holes for the Wires

You will want to drill a hole in your backbox for the wires running to and from your speaker.

Step 7: Install Your Backbox

Installing your backbox is easy. If you have not cut a hole in your drywall already, do so now. You want your back box to fit snuggly against the inner drywall. Gaps can be filled using an acoustic caulk if necessary. Additionally, you will want to fill the wire holes after running your cables through them using putty pads. This helps to seal in sound.

Kirk

Friday 9th of July 2021

We have a loft, with 2X9 joists, where the ceiling speakers are going. The flooring above is OBS with oak flooring, so I think it would be an excellent sound barrier. To reduce materials, can I just cut two sides to save on material, for the back box for the speakers, letting the joists be the other two sides?

Ryan

Sunday 27th of December 2020

Do you install a front plate on your box? Does the box need to be sealed? How are you mounting the speaker? Sorry if it was obvious

Peter

Tuesday 10th of November 2020

Does it make sense to add a hole for air movement like most speakers have in the back of the speaker cabinet? I'm afraid to get it sealed too tight that the driver isn't able to move as freely.