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In-Ceiling Speaker Sizing Guide: What Size Should You Get?

In-ceiling speakers are a popular choice for home theater aficionados. Not only do they help to reduce your speaker setup’s footprint, but they also help provide a more even overhead listening experience. However, in-ceiling speakers will require a more thorough installation process. This means it is even more important that you select the right one from the very start.

So what size in-ceiling speakers should you get? Home theaters over 225 square feet should be equipped with 6- to 8-inch in-ceiling speakers. For rooms up to 100 square feet, 4- to 6-inch speakers may suffice.

Below, I explain the three most popular in-ceiling speaker size as well as the factors that affect which is right for you. And if you’re just starting out with in-ceiling speakers, be sure to check out our other articles on using amplifiers with ceiling speakers, and whether or not you may need to construct a backbox for your in-ceiling speakers.

Understanding the Differences Between In-Ceiling Speaker Sizes

Before I get into the factors you should consider when selecting the appropriate in-ceiling speaker size, it is important you understand what the basic differences are between them. While smaller ceiling speakers like the Herdio 4 inch in-ceiling (on Amazon) can hide easier, larger units like the Polk Audio RC80i (on Amazon) will provide a more powerful, room-filling sound.

4-Inches (Or Smaller)

In-ceiling speakers that are 4-inches or smaller tend to be easier to hide. This makes them one of the top choices when aesthetics are the primary concern. However, speakers that are 4-inches or smaller also tend to be the weaker of the bunch.

Both lower and middle frequencies will often sound weak with these speakers, making them best for small rooms or areas not commonly used for entertainment. That being said – 4-inch speakers tend to be the cheapest available. This makes them the easiest to fit into even the tightest of budgets.


If you are looking for in-ceiling speakers with the best all-around sound, 6-inch models tend to be the most popular. Not only are they able to be flush mounted without providing much distraction to viewers below, but they also have some of the best sound available on the market. For everything, from home theater surround sound to background music, 6-inch in-ceiling speakers offer the best bang for your buck without compromising sound.

8-Inches (Or Larger)

Reputable in-ceiling speakers that are 8-inches or larger tend to have the deepest bass, as well as the best audio range in general. Pay close attention to the quality of the amplifier these will be paired with! You need a decent one in order to maximize the sound produced by the speakers.

However, they also tend to be much more expensive than 4- and 6-inch versions. They are also much more noticeable when installed and can detract from the room’s atmosphere in some cases.

Factors to Consider when Choosing In-Ceiling Speaker Sizes

Larger speakers tend to pack a punch. However, there are a number of factors you need to consider before deciding on which speaker to buy.

Room Size

The size of your room affects the size of the speakers you need, as well as how many should be used. Larger rooms, for example, or those with high ceilings likely need larger speakers, and using a subwoofer in these contexts isn’t a terrible idea either as we’ve explained. This is because space can distort sound, particularly when at maximum volume.

For rooms that are 100 square feet or less, a pair of appropriately sized speakers may be all that is needed.  Rooms that are 225 square feet or larger will likely require two or more pairs of speakers. But what about the rooms between 100- and 225 square feet?

If you opt for speakers that are the next size up, a single pair of in-ceiling speakers may suffice. However, if you plan to stick with smaller speakers, you may want to invest in two pairs for a more balanced sound.

Single Stereo vs Standard Mono

In-ceiling speakers are available in single stereo or standard mono configurations. Standard mono speakers come with a single tweeter and a single bass driver. When appropriately connected to a receiver, the left and right sounds are streamed to the left or right speaker independently.

A single stereo speaker, however, has a both a left and right tweeter, as well as a bass driver. This allows a single speaker to stream both left and right sounds.

Most experts recommend standard mono speakers for rooms that are 100 square feet or bigger. For smaller rooms, such as a small bedroom, a single stereo speaker is recommended.

When using a pair of standard mono speakers, this allows each speaker to stream coordinating sounds flawlessly instead of mixing left and right from a single source.

Round vs Square Speakers

Where you decide to place your in-ceiling speakers also affects the size you need. If you are looking to place one pair of large speakers in the middle of a room, this may be sufficient.

However, if you are looking to install smaller speakers or trying to outfit an irregularly shaped room, you may want to consider multiple sets. Large speakers in an L-shaped room may not provide even sound, whereas multiple sets of smaller speakers may deliver the surround sound you are looking for.

Primary Purpose

The primary purpose for your speakers also affects their size. If you are looking to install in-ceiling speakers that mostly support background music, smaller speakers can provide that. For true surround sound, however, you will want to invest in speakers that pack a punch.

This can usually be found in 6- and 8-inch speakers. This is because the medium to larger sized speakers often some with better quality drivers, which help the dynamic tones featured in home theater applications to ring true.

Multi-Channel Capabilities

If you are planning to include in-ceiling speakers in a multi-channel configuration, you need to consider the quality of all components. If you are combining them with wall-mounted speakers or floor models, the sound quality should be comparable.

This may mean that 8-inch speakers are too powerful for your configuration and a pair or two of smaller speakers will provide a much more even sound. If your in-ceiling speakers provide sound that is more powerful or weaker than your other speakers, it can detract from the desired surround sound.

Power Source

Your speakers’ power source is also an important factor. Larger in-ceiling speakers will require more power (more on that in our guide). If your receiver or amplifier cannot deliver the required power, your speakers will not work properly. (In fact, some may not even work at all.) if you already have a receiver and do not want to upgrade, you will need to invest in speakers that work with your device.

Required Ceiling Space

Different in-ceiling speakers will require different installation spaces, similar to what can be seen inside vehicles as well (more on the differences in our guide). For example, one of the slimmest in-ceiling speakers on the market requires a mounting depth of 33 millimeters (mm) and a cutout measuring 196mm in diameter.

However, another model of comparable size requires a depth of 250mm. When mounting a speaker in your ceiling, you’ll need to pay attention to the actual space available for the entire box to be installed.