How Many Acoustic Panels Do I Need?
Acoustic panels are instrumental to any soundproofing process. But one problem you may experience when soundproofing a place is deciding how many panels to use. There are several factors to consider before choosing panels, and many of them may not be up to you.
Luckily, the decision is fairly easy to make once you consider a few factors. Let’s take a look at each of them.
Do acoustic panels absorb sound or block it?
People often confuse these two terms, and for a good reason. They both refer to diminishing the effects/disturbance of sound in a particular space. However, soundproofing is much different from sound absorption. Acoustic panels are used for soundproofing, not sound absorption.
You would normally install the panels on your walls after construction. The best they can do is absorb most of the sound they encounter, and even though some sound will leak to the other side, it will be much quieter.
Sound blocking is done using acoustic barriers placed inside the walls during construction. They can also be a part of the construction material, and they keep sound from passing to the other side.
Do I need sound blocking or soundproofing?
The chances are that you’ll need soundproofing. We say this without knowing your specific needs due to two reasons.
Firstly, soundproofing is sufficient for most people’s needs. Whether you’re setting up a home cinema, establishing a studio, or just looking for an ultra-quiet room, soundproofing will meet your needs just fine. The acoustic panels will keep the sound from escaping and bounce it back to you.
Secondly, unless you built acoustic barriers into the walls, sound blocking a room can be very difficult. As we stated earlier, the materials used are usually inside or a part of the construction materials. Thus, you may not be able to sound block your space without parting with a lot of cash.
What are the types of acoustic panels?
Acoustic panels exist in many shapes and sizes. And even though they perform similar functions, the kind of panels you get often depends on the space you’re fitting in, because they can impact the overall aesthetic.
Here are three kinds of acoustic panels:
- Art acoustic panels
Art acoustic panels are customizable, and they soundproof while also highlighting your design preferences. They are infused with rich colors or images and are suitable for all kinds of spaces, including auditoriums, bars and restaurants, and even office spaces.
- Fabric-wrapped panels
Fabric-wrapped panels, as the name suggests, have fabric finishes. They have remarkable acoustic properties and often deliver incredible silence. And since they are panels, they can be hung or mounted, minimizing installation time. Fabric wrapped panels are especially favored for their aesthetic appeal.
- Perforated acoustic wood panels
These have a different make-up to the other two panel types. While others are made of mineral wool, fiberglass, cellulose, and open-cell foam, perforated acoustic wood panels are made of fiberboard. They may also have variable finishes, including plywood, melamine, or varnish. Perforated wood panels are some of the most economical acoustic treatments.
What determines the number of acoustic panels I need?
Now that you’re familiar with how acoustic panels work and the different types, it’s time to answer the all-important question: How many do you need.
A standard rectangular room will need around 18 panels.
You may read this and think, “what if my room is bigger or smaller?”
The truth is, you’ll be hard-pressed to find a straightforward answer without talking to a professional because there are many factors to consider.
The most obvious one is the size of your room. A larger space may need more panels or at least bigger ones. If you intend to install panels on the ceiling for additional soundproofing, you’ll obviously also need more. You also need to think about the kind of walls, number of windows and doors, and the room’s shape.
Two more significant points to consider are reflection points and bass traps.
Reflection points
Reflection points refer to the sound sources in a room. They are the exact area where the sound from a speaker hits the walls in the room. Generally, a sound source will reflect each wall, except the wall behind it.
How to find reflection points?
You need acoustic panels for each of these points (2-inch-thick panels may be sufficient for most people). Finding reflection points is tricky, and it’s best to get an expert to handle the whole process.
But if you feel like DIY-ing it, get some masking tape, a small mirror, and an extra pair of hands. Mark each speaker with masking tape, get your mirror, and try to find the reflection on the opposite wall.
Have your friend stand beside the speaker until they see the reflection. Wherever the reflection happens to be is the reflection point on the opposite wall. Move to the next wall and find the reflection again. Do this for all the walls in your room.
Bass traps
Bass traps improve your room’s acoustic property by trapping low-end frequency noises. The goal with bass traps is to dampen low-frequency sounds and reduce resonance in the room. Bass traps are usually installed in theaters, recording studios, and other rooms that require acute listening.
Where to place acoustic panels in home theater:
You’ll need acoustic panels to cover reflection points for each of your theater’s sound sources. In this way, your installation cost, and the number of panels you need, correlate directly with how many speakers you have.
The main priorities are reflection points on the opposite and adjacent walls of the speakers. (reflection points on the floor and ceiling can come later). The walls behind your speakers don’t need any panels because most speakers are treated for soundproofing from behind.
The most straightforward approach with bass traps is to install floor-to-ceiling bass traps in every corner of the room because maximum bass is reflected from there. It is also recommended that you get 4” thick bass traps instead of the 2” thick materials for reflection points.
Some people go as far as installing bass traps on the ceiling and floor corners of the room, although these are likely to blow up your budget.
Putting It All Together
Assuming you have a rectangular or square room, you’ll need three acoustic panels per speaker. These will go on each wall except the one behind the speaker.
So if you have five speakers, that's 15 acoustic panels.
A step further would be to install panels at the reflection points on the floor and ceiling as well. If you take this option, that’s five panels per speaker or 25 panels for five speakers.
Bass traps usually go in each corner, so you’ll only need four in our rectangular room’s case.