Home theatres are all about those surround-sound Atmos speakers, prime seating, amazing visuals, and most importantly, balanced acoustics!
All you need to know when deciding where and how to place acoustic panels in home theatre are some elementary acoustic principles. Acoustic panels need to be placed at certain specific positions/angles in a room to absorb the reflecting sound waves efficiently. And once you know what the right spot is, installation is pretty straightforward!
Smashing speakers, state-of-the-art materials, top-notch technology are only part of a great-sounding theatre. The real results depend on the right placement of seats, acoustic panels, and speakers in a home theatre. The first step would actually be to buy one of our top recommendations for the best acoustic panels for home theaters. After that, you can:
Start With Speaker Calibration
Calibration is a technique that helps you get the perfect listening experience from your sitting position. It involves adjusting the speakers according to your ideal listening spots with the help of a microphone kit.
This correction system requires you to place the microphones in primary seating positions, and play test tones to detect the peaks and valleys. Correction helps narrow down the dips to the max and brings down the peaks for more and better bass responses.
When calibrating your home theatre, you’ll make minor tweaks and adjust placement until everything sounds perfect. You have to make sure all the speakers are balanced, not too loud not too soft. The goal of calibrating your audio system for home theatre is to just achieve an even frequency response at the prime listening point.
Every pre-processor and AVR (Audio Video Receiver) comes with a calibration feature. This feature allows you to adjust and correct speaker timings, equalization, and levels.
Calibration mainly compensates for any discrepancies in your equipment and environment. This process can help you yield incredibly accurate frequency response, powerful bass, and great dialogue intelligibility.
Remember, you will have to re-apply the settings if you change the placement of the furniture in the room or add drapery or more acoustic panels, etc.
Why Do You Need Acoustic Panels in Home Theatre?
Where and how to place acoustic panels in home theatre is all physics. The answer to this “why”, again, is all simple physics of sound!
These are some of the main reasons why acoustic panels are used in a home theatre.
Controlling reflections is the primary purpose of an acoustic panel. Sound waves bounce off of every wall, ceiling, floor, desk, or other hard surfaces. Each speaker placed in your theatre will have its own specific reflection point that will affect the prime listening position.
There are a total of five reflection points for each speaker, one on each wall of the theatre (excluding the one behind the speaker), the floor, and one on the ceiling. Speakers are usually shielded from behind so the walls behind them can sometimes be ignored.
For a typical 5.1 surround sound system in a standard-sized home theatre, there will be around 25 reflection points for five speakers. These points are located on the front, surround, and center speakers. All these points need to be treated differently for different ranges of frequency.
How to find reflection points? Easy! All you need is a small mirror and a friend to assist you. Your friend will have to hold the mirror against the wall and move it across till a point where you (seated at the listening position) can see the reflection of the speaker. This point is the reflection point of that speaker on that specific wall. Mark it!
Repeat this process for every wall and you’ll have reflection points where you need to place acoustic panels. Acoustic panels covering these points will absorb all the problematic sound waves and minimize maximum reflections.
This covers the lowest of bass rumbles to the shrillest high-frequency sounds.
Low bass sounds from subwoofers or the speakers bounce around the theatre after they hit a hard surface. These bouncing low-frequency waves can create two kinds of issues depending on the dimensions of the room.
What happens is that these low bass tones or low-frequency sound waves build up in corners of the studio. And the density of such “build-ups” mainly depends on the dimensions of the room. The first issue they can create is their complete cancellation by the reflections in the theatre, and the result is a very low bass.
Secondly, the sound notes or tones other than the canceled ones will get more conspicuous and overwhelm other room frequencies. This creates room modes. Equal dimensions of a room usually create more problematic modes.
As a general rule of thumb, the smaller your theatre room, the more problems you’re going to have while balancing sound in it.
As discussed earlier, bass modes are created when sound waves build up in the room’s corners. They can mess up the quality of high and mid-range sound waves as well. To tame the long wavelengths of such bassy tones, you need to place bass traps in the corners.
These bass traps are quite large and completely sip in low bass note reflections due to their thick and dense foamy construction. Bass modes also tend to smooth out if you add multiple sources of energy to the room. This means the addition of two or more subwoofers to the theatre.
Moreover, when selecting or building a home studio, you need to pick a rectangular-shaped room for the best sonic experience. The golden ratio is something like 1:1.6:2.6, which is the height, length, and width of the room.
The biggest problem with high sound frequencies is echo and reverberations! You cannot experience the emotion or subtleties of voice or music if your studio isn’t treated for high-frequency sound waves.
The best way to mellow them down is to use soft and absorptive material which, in a home theatre, means acoustic foam or panels. Acoustic panels help to eliminate the chances of bouncing waves from the first reflection points to limit the echo.
These frequencies have shorter wavelengths and can lose their kinetic energy comparatively earlier than the low-frequency waves. This is why acoustic panels with soft and thin foam at the core are perfect for taming high-frequency sound waves.
Where to Place Acoustic Panels in Home Theater
It’s quite evident from the explanation above that you need not throw acoustic panels just randomly around the room. 15% to 30% (optimally 25%) wall coverage is usually considered ideal for providing enough absorption for echo and for bringing the reverberant field under control.
Here are some general guidelines regarding the placement of acoustic panels in home theatre to achieve balanced sound free from front-to-back room chatter.
First Reflection Points
First reflections, also known as direct sound, are the sound waves that reach the listener before other reflected sound waves arrive. The mirror trick mentioned earlier is used to find the first reflection points in a home theatre.
Take special care of the front and center speakers as they blurt out most of the music and dialogue. You will have to place acoustic panels of around two inches thickness on each side wall and reflection points for these speakers.
Other Reflection Points
These are the reflection points on the floor, ceiling, front and back walls. It is impossible to put acoustic panels on the floor. However, using a combination of throw rugs and carpets for the front and center speakers can mitigate some of the damage.
The back of all kinds of speakers are perfectly covered and the walls behind them aren’t at the risk of direct reflections. But these walls can receive other reflected bouncing waves from around the room. Place at least two acoustic absorption panels at the back wall.
The same goes for the front wall, but this wall would need two or three acoustic panels of 2ft width to catch all the waves from the front-firing speakers. This helps in achieving a better sound stage for the theatre.
Acoustic panels on the ceiling are definitely a second priority as the speakers are at a considerable distance. Walls and floor hold the first reflection points, you would only need to place two panels on the ceiling to cover the center and the front speaker reflections.
The front corners of a home theatre need bass traps that are at least 4-inches in thickness. Maximum bass can reflect and muster up in the front corners, this is why you’d need to place two bass traps in each corner for perfect absorption.
Rear and Intersecting Corners
The rear corner is also a prime point for low-frequency sound waves to gather. A lot of the bass is reflected from these corners and would need at least two 4-inches acoustic panels in each rear corner.
Other than the mainstream points, the area where the ceiling/floor and the wall intersect can also cause problems. You can place bass traps in these corners as well to enhance the overall sound quality in the home theatre.
How to Hang/Install Acoustic Panels in Home Theatre?
Acoustic panels used in a home theatre are mostly fabric-wrapped ones. Their installation process is indeed pretty simple.
There are two installation systems followed;
- Snap-On Mounting System
- Z-Clip System
Method 1 – Snap-On Mounting System
You’d need the following list of materials and equipment to carry out this installation:
- An appropriate number of acoustic panels
- Mounting hardware (if available)
- Measuring tape
- Power drill
- Pencil or pen for marking
- 1½” wood screw
Measure the edge of the boundary (window, wall, ceiling, or door) from the side-edge line of the desired location of the panel and mark the distance. Also, measure the distance from the floor to the desired top position of the panel.
After marking the horizontal and vertical edge lines, attach T-Handle to the back of the panel at the snap anchor. Place and screw snap anchors 2-3 inches inside the edges of the panel and add plugs into the openings after the snap anchor is tight.
Then, position the panels on the wall where you made the marks earlier and lightly hit the corners to indent the wall at plug points. Remove the panel to see the anchor locations from the marker plugs on the wall. Screw wall anchors into these indentations and screw anchor ratchet insert there. Position the panel at the ratchet inserts and press firmly at each corner.
Method 2 – Z-Clip Mounting System
- Marking pencil
- Measuring tape
- 1 ½” wood screws
- Power drill
Screw the four Z-clips in the round center holes in the pre-installed square metal plates at the back of the panel. Make sure that the top and bottom pairs of Z-clips are aligned with each other. Then add the second screw to each Z-clip outside the hole location. Place Z-bars in the Z-clips for the next step.
Measure from the top edge of the panel to the end of the top Z-bar and note the measurement. Remove Z-Bars and mark the wall at the side and top-edge position for the desired location of the panel. Draw vertical and horizontal lines using a level.
From the top horizontal line on the wall, measure to locate the top Z-bar placement location marked earlier. Then mark the top and bottom (and their centers from the side-edge line) horizontal lines on the wall using a level.
Place the top Z-bar on the horizontal line drawn and position the center hole at the marked center of the line. Punch the indentation at the sides and the center from top and bottom Z-bars. Drill at the side and center wall anchors or both top and bottom Z-bars at each wall indentation. Screw and attach Z-bars to the wall and position the acoustic panel centered on Z-clips. Press and fit it into the Z-bars.
FAQs – Acoustic Panels for Home Theatre
How many acoustic panels do I need for Home Theatre?
This depends solely on what your room looks like. Sound waves behave differently in different spaces, all you need to do is to identify treatment points in your theatre. These spots tell you the location of your acoustic panels.
An average home theatre usually utilizes around 10-18 acoustic panels placed at the front, rear and side walls, with at least 8 bass traps in the corners.
Can I hang acoustic panels in Home Studio with command strips?
No! Because usually, the acoustic panels used in home studios are larger and resultantly much heavier. Even if you get some luck hanging them, they won’t stay there for long as command strips cannot bear heavyweights.
However, 3M command strips can be used to hang very small acoustic panels or acoustic foam easily.
Are acoustic panels necessary in a Home Theatre?
Yes! A home theatre without acoustic treatment on its walls, ceiling, and corners will have all kinds of sound waves reflecting from all kinds of surfaces in all kinds of directions. This will defy the whole purpose of a home theatre.
Acoustic panels reduce lingering reflections by absorbing unwanted sound waves coming their way. They attenuate noise, chatter, and echoes so the listener receives crisp and clear sounds from the speakers.
How to acoustically treat a Home Theatre?
A simple rule is to replace all hard, reflective, or shiny surfaces with soft, permeable ones. Soft surfaces when placed at the right positions will absorb sound waves. You can also use soft and heavy curtains, cushions, or rugs in addition to the installation of high NRC-rated acoustic panels.
Bass traps for low-frequency absorption and curve diffusers can also be used in combination to achieve the perfect sonic environment.
Can I use standing acoustic panels in Home Theatre?
Yes, you can use standing acoustic panels in home theatre as long as they don’t collide with the aesthetics of the theatre. Performance-wise they are no different from hanging acoustic panels.
Make sure that when you place the freestanding acoustic panel against the wall you leave a 100mm gap between the panel and the wall. This will increase the low-end absorption of the panel.
What is the cheapest way to acoustically treat Home Theatre?
The cheapest option perhaps is building your own acoustic panels. DIY acoustic panels are less likely to perform like professional-grade panels but they’ll work for echoes and resonances.
How to build your own acoustic panels?
It’s pretty simple! You’d need to build a wooden frame and fill it with insulating, soft material. The absorptive material is ideally foam that makes the core of the panel. Cover this wooden frame with a porous fabric that should allow the passage of sound waves. And Voila! Your acoustic panel is ready.
Hang the panels and enjoy the balanced sound from all around!