Do You Need Acoustic Panels For Home Theaters? Depending on your priorities, needs, and goals, there are a few factors to consider.
For many people, having a home theater is a dream come true. Some of them may have a simple setup comprised of a large screen TV and a comfortable couch or recliner. Others will go all out and create a home theater based on commercial cinemas, complete with movie posters, fountain drinks, popcorn makers, and authentic theater seating.
Still, others might let their imaginations run wild and recreate a setting or scene from a favourite movie or TV show. The choices are limited only by the amount of space and available budget.
Whatever kind of setup they may choose, however, most homeowners who invest in a home theater will make it the best they can. Often, that will mean focusing on the picture. Whether they are using a projector or a large screen TV, they want their movies, sporting events, and TV shows to look great.
Adding a high-quality sound system is also a must for many. As great as a movie may look, it can always be improved and made more immersive with the proper audio. Multiple speakers will be placed in strategic locations to provide the best surround sound experience. If you have already invested in an excellent screen and top-notch sound system, you may be wondering if there is anything else you can do to put your home theater over the top.
It may surprise you to know that simply having an excellent sound system is not enough to obtain the best sound experience. Your surround sound system comes with certain challenges that can make the sound less than perfect.
Today’s TVs can provide incredible detail, showing minute changes in facial expressions, tiny freckles on an actor’s nose, the texture of fabrics and other materials, and more. Your audio should be able to offer the same level of detail. Voices should be clear and crisp, allowing you to catch subtle inflections and the emotional content of the actor’s performance. If that is lost due to improper sound, you are not enjoying your content the way it was intended.
To reach this level of great sound, you will need to plan your speaker layout and create an acoustic signature in your room that enhances the sound, rather than diminishes it. Doing this requires not only a proper system setup, but also looking beyond your sound system and understanding the role of acoustic panels for home theaters.
You have probably already seen acoustic panels, even if you didn’t recognize them for what they were. They are used in cinemas, home theaters, sound stages, production studios, and anywhere else that relies on perfect sound.
What Are Acoustic Panels?
Acoustic panels for home theaters are typically made of shaped foam with a fabric covering and are intended to absorb sound waves. If you have invested in a great audio system, you may find it counter-intuitive that you should want the sound to be absorbed, but acoustic panels keep the sound waves from reverberating throughout the room and reducing the quality of other sound waves. As odd as it might seem, reducing the number of sound waves in the room will have an end result of improving the sound.
How Do Acoustic Panels Work?
The sound we hear is essentially vibration moving through the air. That sound can bounce off objects. Bats rely on this to use their echolocation, emitting sound that bounces off objects to return to their ears. Imagine multiple sound waves bouncing around your home theater at the same time. This might make it difficult for the bat to navigate, and it also impacts your ability to hear certain sounds. Smaller rooms and those with equal dimensions tend to be the most problematic.
Some panels may feature exposed surfaces with triangular points. These help to trap the sound waves, and it is here where they expend all their energy bouncing back and forth. Other panels simply allow the absorbent nature of their foam construction to contain the waves.
In a room without acoustic panels, the sound waves will hit the walls and ceiling and bounce away again. The low bass tone from your subwoofer can build up in your room causing some tones to be cancelled out while causing others to become more pronounced. In smaller rooms, higher tones can negatively impact the sound quality, causing you to lose detail. By preventing this from happening, acoustic panels clean up the sound you are experiencing.
Sound waves come in different wavelengths, meaning there are two main types of acoustic panels to deal with them. Normal wall panels function with mid and high-frequency sound waves, while “bass traps” are panels that sit in the corners of the room and work with lower-frequency sounds.
Parts of an Acoustic Panel
As mentioned above, acoustic panels are typically created with foam and often also have a fabric covering. In fact, while the panels all work in the same basic way, there are various materials, such as compressed wool, that can be put to use, so long as they are porous enough for the sound to enter but dense enough that it bounces around in the panel and cannot escape.
The fabric acts as a cover for the foam, making it more aesthetically pleasing. It too needs to be porous enough to let sound pass through, but that still leaves many options.
Reverberation (or simply reverb) is what you are hearing when the sound is produced. Some of the sound waves will go directly to you from the speaker, but they also are spread throughout the room, either bouncing off or absorbed by whatever they hit. The reverberation is like an echo, but because it is a small, contained space, the sound that bounces back occurs at virtually the same time as the direct sound.
If you have been in an empty room surrounded only by drywall—such as when moving into a new home—then you are likely familiar with what this sounds like. Imagine trying to watch a movie with a similar effect occurring. You wouldn’t be able to pick up on the subtleties of voice that some great actors use to convey emotion. This is what makes it so important to control reverberation.
Are Acoustic Panels Effective?
Acoustic panels for home theaters can provide excellent results when used correctly. In the case of someone with a high-quality surround sound system, or even a soundbar with 3.1 or 5.2 channels, acoustic panels can be quite effective, as there can be enough sound waves bouncing around to create issues.
Chances are good that you don’t have much covering many of your walls. With multiple speakers directing sound in different directions, the sound waves will be striking the hard surfaces of your walls and ceiling. In some cases, this is not a problem, but as you increase the number of speakers and the volume, there starts to be too much sound in the area. The sound waves will start bouncing not only off the walls but each other as well. At this point, you will have invested in a high-quality sound system, but will not be receiving high-quality sound.
Fortunately, this is the exact problem that acoustic panels were designed to solve, though it takes more than simply throwing a few on the wall and you won’t want to buy more than you actually need, so placing them correctly is important.
To help position everything correctly, visualize the sound waves as they might appear in your room. Begin by having the speakers facing you wherever you will be seated. Where is your main source of the sound? This speaker will be the direct sound source.
A useful trick involves having a helper with a mirror. Have them hold the mirror against the wall to either your left or your right, at the height of your head. Have them move the mirror until it is positioned in such a way that you can see the speaker in it. When you do, it will be sitting in the position where sound waves from the speaker will bounce off the wall on their way to you. Light is a wave, like sound, so this method will reveal to you the path that sound waves will take upon leaving the speaker and these are the most critical spots for your acoustic panels. This will work to “catch” the sound waves to keep them from bouncing back to you. Additionally, you can arrange the panels in a way that sound waves that pass by you will be absorbed rather than bouncing back.
If you have a soundbar in front of you, for example, you should have panels behind you at the back of the room. Side speakers that are aimed diagonally toward your seat should also have panels opposite them, wherever their sound waves would strike the walls. Panels placed correctly will result in an improved audio experience.
Don’t Forget the Ceiling
So far, we have discussed the walls, but while your walls may reflect sound by being mostly bare, your ceiling is likely to be completely bare. Is it advisable to mount acoustic panels on the ceiling? Because it is completely bare, your ceiling may actually be even worse than the walls when it comes to reflecting sound. At least your walls will be partially blocked by furniture.
You can certainly place acoustic panels on your ceiling, which can further enhance the effect of canceling out unwanted sound. You may need to work out a plan for their installation, however, if lighting poses an issue or you have a projector. Use the same mirror method to find the direct line from the speaker so that you know where to mount your panels.
As for the actual mounting of the panels, to get proper results you will need to drill into the joists behind the ceiling with screw eyelets. Your panels can then be attached to the eyelets using zip-ties, which will improve their performance by leaving a small gap (about 2.5 cm or 1 inch) between the panel and the ceiling.
Low-Frequency Sounds Call for Bass Traps
Some of the sound waves—specifically, the deeper ones have a very long wavelength. As a result, they do not behave in the same manner as shorter waves. They have considerably more energy, which means that scattering them is ineffectual. Unfortunately, trying to absorb them is difficult when using a normal absorbing panel. So how are they handled?
To deal with these particular sound waves, there are special acoustic panels that are sometimes referred to as bass traps. As the name implies, they are designed to trap the bass sound waves. Bass traps will be placed in the corners of the room. Typically, there will be three of them in each direction, with a simple square foam block serving as an anchor.
As with other acoustic panels, these work by catching the sound waves and trapping them within their ridges, where they will continually bounce until they use up their energy. In many cases, the benefits of using Bass Traps are pretty small, so it is more important to start with the rest of the room and then determine if you really need to proceed with them.
Do You Need Acoustic Panels?
Many homeowners with home theaters do not have acoustic panels, so it’s valid to ask whether you truly need them or not. Certainly, they may not be required in every instance. If your home theater does not include any speakers and you rely solely on those built into your TV, you may not feel the need for them.
If you are trying for high-quality sound, perhaps from a Dolby Atmos source, then you will likely want to add acoustic panels to ensure that you get the absolute best sound out of your system. With a bit of planning, proper speaker placement, and the use of acoustic panels, there is no reason why your audio shouldn’t be as impressive and engaging as your TV’s picture.
Once you have the perfect sound system and perfect acoustic panels, don’t forget to get the perfect custom home theater chair from Elite HTS.