Now, when I bought my top-of-the-line home theater system, my intention was to improve my listening experience by having a powerful machine that would offer me that room-shaking bass I was craving for when watching my favorite blockbuster movies. Besides, I needed a sound system that could reproduce blasting bass whenever I invited my friends over for a party. Since I was aware that my listening experience would have some hollowness without the weight and foundation of the low frequencies, I was keen to add a powerful subwoofer that could improve the sonic potential of my full-range speakers.
But, after such a huge investment, I came to realize that most of my neighbors were complaining about my sound system being too loud. At first, I assumed the complaints were baseless since most of my neighbors, especially those above and below my apartment, were seniors. However, following a series of complaints, I decided to conduct some research on whether a subwoofer can damage a house. What I discovered was quite alarming.
So, in this post, I will explain how low frequencies are felt rather than heard. I will also explain cases where low-frequency bass waves go beyond sound to become tactile infra-sound sensations that are responsible for the earth-trembling vibrations. Lastly, I will explain how subwoofer vibrations can be dampened to avoid causing annoyance and structural damage.
How is Sound Felt?
When I first thought of this topic, my quick answer was a big NO; subwoofer vibrations cannot cause structural damage. After all, movie theaters don’t experience any structural damage, right? But, when you dig deep into numerous research conducted, you’ll notice that there’s some truth in it. If we get to subwoofers just a little bit, you’ll realize that there are those factors that affect a subwoofer’s output.
For instance, a subwoofer with a powerful motor and a large/heavy driver will move a lot of air due to the great back and forth excursions. What this means is that such a sub will generate massive sonic energy and ensuing vibrations that will be transferred throughout the room via the floor. Since your apartment is turned into a giant diaphragm, the vibrations generated become so intense that they become somewhat disturbing to your neighbors.
To understand how sound is felt; you need to first understand the anatomy of the low-frequency waves. These waves are usually categorized into three. There’s the deep frequency (ranging from 10-25Hz), mid-bass (from 31.5-80Hz) and lastly, there’s the upper bass (ranging from 100-200Hz).
In most cases, the upper and mid-bass are quite easy to detect with your ears as it’s the one responsible for the chest punching bass you usually hear. However, things get a little bit different when it comes to the deep frequency. This type of low-frequency is the one responsible for the abnormal vibrations usually known as mechanical vibrations. These types of vibrations are the ones responsible for the deep earth trembling bass that causes items in your room such as wallpapers and pictures to fall off as well as items on shelves and cupboards to rattle.
Another type of deep frequency wave is infra-sound. This type of low-frequency wave is usually below the 20Hz threshold. Since this frequency is usually inaudible by the human ear, it can only be felt rather than be heard. Due to this reason, this type of low-frequency is responsible for the annoying vibrations you usually hear and can also cause structural damage at some point.
So, How Can You Reduce Subwoofer Vibrations?
Just before I move on to the solution, let me remind you that vibrations from your subwoofer are responsible for a phenomenon known as microphonics. These are actually the mechanical shocks or vibrations caused by your subwoofer that result in the earth-trembling effect responsible for rattling and structural damage. So, to reduce these vibrations to the minimum, here are some remedies you can consider.
Decoupling Your Subwoofer
The first solution you can try out is to decouple your subwoofer from the floor. Decoupling a subwoofer means raising it a little higher to minimize direct contact with the floor. To do this, you can use rubber feet, metal spikes, speaker stands, or metal decoupling pegs to raise it higher from the floor.
Using Isolation Pads
Another remedy you can try out to solve this issue of vibrations is by using isolation pads. Although these pads come in all manner of shapes and materials, the best ones to consider are the ones made of spongy or rubber materials with air gaps in between them. Since your floor is like a giant resonator that allows sound to pass through, using isolation pads means that you’ll successfully dampen the vibrations before they move from the subwoofer to the floor.
Using Bass Traps
Both of these two methods I’ve discussed above are perfectly implemented if you’re looking to reduce vibrations from reaching the floor. However, if you’re looking to stop sound waves from hitting the walls and creating more intense vibrations, then you need to consider the convenience of adding acoustic treatment bass traps.
Similar to isolation pads, bass traps work by absorbing sound that’s bouncing from your sub to the walls. The only difference is that they’re mounted on the walls, especially on the corners, instead of being on the floor.
That’s all for today. In case you’ve been wondering whether a subwoofer can cause structural damage to a house, then this post has shed some light on your assumption. As you can see, subwoofers are engineered to reproduce bass at different frequencies. While anything greater than 50Hz is considered to be decent, anything lower than that is classified as the deep frequency which is responsible for the mechanical vibrations that cause structural damage. However, for this to happen, your subwoofer must have a strong motor and a large/powerful driver.
Thankfully, as a solution to these annoying vibrations, I’ve managed to discuss three common methods you can apply to dampen mechanical vibrations from not only causing structural damage but also disturbing the peace of your immediate neighbors in case you live in an apartment, a duplex or a condo unit.