When putting up acoustic treatment, there are bound to be questions popping up throughout the process. Whether or not there should be an air gap between acoustic treatment is something most might not think of until they are in the middle of the process.
Leave and air gap behind acoustic panels? It’s recommended to leave an air gap behind any acoustic treatment. Not only does it help increase overall absorption, but it effectively extends the range of the treatment into lower frequencies.
Leaving an air gap is also great when it comes to bass trapping and similar effects for the average person.
What’s the Effectiveness of an Air Gap behind Acoustic Panels
Most people get thrown off by the fact that an air gap is beneficial with any type of acoustic panel setup in the office or at home.
Many would think that mounting the panels right up against the wall would be the way to go. These panels indeed add more mass to the existing wall when put right up against them.
The reason why it’s a little bit better to have some type of air gap is that low-frequency absorption is much improved when the panel is slightly away from the wall.
Whenever new acoustic panels are placed on the wall, putting a spacer in allows the rear surface to also absorb sound.
Air gaps, when done the right way, can increase absorption by close to 50%. It also extends absorption coverage to some lower frequencies that are uncovered by flat wall mounting.
How Much Space Should be Between Wall and Acoustic Panels?
The more air gap a person can put between the wall and the treatment, the better (from a low-frequency perspective).
However, as the air gap becomes bigger than the acoustic panel treatment itself, there becomes an issue with the mid frequencies.
All this happens because the treatment doesn’t sit in the proper spot to handle initial absorption more traditionally. The low frequencies are always handled with ease, but the mid frequencies become an issue.
The happy medium that a lot of people find is that they don’t want to make the air gap any larger than the material itself.
If the panel is two inches thick, the air gap needs to be two inches or less. This setup provides the best overall sound and allows people to feel pretty confident that it will work for a long time.
Play around with the different setups within those parameters, and see what works specifically for a room. Every room may be slightly different, and the same goes for what people want out of their sound. (Source)
Can An Air Gap Also Help Eliminate Standing Waves?
The phenomenon known as standing waves is when soundwaves will bounce back and forth between two parallel surfaces in a room.
When the direct and reflective signals combine, there are a lot of peaks and dips that can cause trouble. It’s not something a lot of people want to deal with if it’s avoidable.
By including an air gap on both sides, it’s a lot easier to mount acoustic treatment with a slight slant. If the panels are at a little bit of an angle, there are fewer parallel surfaces in the entire room.
Keep in mind that slanting the treatment doesn’t need to be too extreme to have effectiveness. Look at it much like looking at actual mirrors reflecting off of each other.
They don’t need to be put at any extreme angles, but they do need to be angled away so that they don’t make a direct connection.
Getting the Most Out of Acoustic Treatment
Acoustic treatment, at the very basis of it, is extremely important. Whether a person is doing some home recording or setting up a new professional studio, any type of sound reflecting off of bare walls can ruin even the best sound. Flat, hard surfaces are a nightmare to deal with.
There are no amount of tricks that can correct these hard wall issues, so going with acoustic panel treatment is key.
The smaller a room is, the more important it is to have acoustic treatment. One of the benefits of using an air gap is that it maximizes the effectiveness of whatever treatment is used.
Sometimes, people don’t have the money to spend a ton on acoustic treatment. It’s better to do some of the smaller tricks that will help maximize the effectiveness, instead of paying hundreds if not thousands of more dollars.
With all that said, the costly acoustic treatment will last a longer amount of time and be more effective when compared to other options.
They do a great job with air gaps, and most find they can get a slightly larger air gap with better quality treatment.
Since the acoustic treatment is doing a lot of the heavy lifting controlling sound, the air gap doesn’t need to be as tight to the wall.
The Cons of an Air Gap Behind Acoustic Treatment?
While most of this article is focused on the positives, there are some negatives to an air gap behind the acoustic treatment. Maybe the biggest negative is the extra space it takes up in a room.
Everyone wants to maximize as much space as possible when setting up their new room. One way to maximize that space is by using thicker panels and a slightly smaller air gap.
That would have more of an impact than thinner panels with a huge air gap. At the end of the day, this is merely an inch or two for the most part. Most are willing to compromise a bit if the difference is noticeable.
Other than those issues, there aren’t any other negatives for people to be worried about. It takes a little bit of extra time to set up the proper air gap, but it gets easier and easier with each panel.
There’s also the option of getting a professional team to take care of the acoustics in a room. They’ll be able to better gauge just how much of an air gap is ideal. They’ll have actual tools to do quick measurements on sound.
Why Air Gaps Should Be Part of the Next Acoustic Panel Placement
At this point, there’s no reason not to do whatever possible to get some type of air gap behind acoustic panel placement.
Unless it is a super tiny room that can’t spare any additional space, the positives are going to far outweigh the negatives.
Keep in mind that large rooms probably won’t make that much of a difference with an air gap, but it’s still worth slightly more effort. Anyone who’s had particular issues with low frequencies in the past should keep this in mind.
There’s always going to be a little bit of give-and-take when trying out new setups with acoustic panels.
As long as people keep in mind that the air gap should never be any larger than the depth of the material, they should be good to go.
High-quality material can usually get away with slightly bigger air gaps, maximizing effectiveness. Depending on the use of the room, people might go in one direction or the other with what they think sounds best.