Anybody who loves their music has to approve of at least a little bit of bass. Even if all you prefer is classical music, a subwoofer gives it some life and depth that it previously lacked.
On the flip side, you’ve probably heard that car coming down the street with the bass so high that the metal of the trunk vibrates.
It usually sounds pretty awful. When you have a bunch of moving parts located close to a powerful subwoofer, like a trunk on hinges, it will rattle the trunk so hard that the sound of the vibrating trunk often drowns out the sound of the bass.
If it can get so loud that it visibly vibrates a trunk, what can a subwoofer do to glass?
So, do you have to be worried about the windows in your home or car? If a sub is cranked up to a high enough level, does it stand a chance of shattering the glass around it?
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Can A Subwoofer Break Glass?
It’s very unlikely that a subwoofer will break glass. The sub would have to match the resonance frequency of the glass for it to break but, in most cases, you have to reach well over 100db to break even the most delicate glass. A subwoofer doesn’t reach the decibels that standard speakers do at the same volume. Most find that a level of 70 to 75dB is a comfortable playback level for bass.
On rare occurrences, subs, as part of some of the most extreme car speaker setups in the world – like the ones used in competitions – can blow out car windows. but even then it’s rare.
In the home, it’s even rarer or completely unheard of, considering you would have to have your subwoofer facing a piece of glass, inches from it, and cranked up to the max. Not going to happen by accident.
You could physically pick up a subwoofer and chuck it through a window if you really want to test the theory on subwoofers breaking glass but that’s about as close as you will get. Glass vibrates as it is struck with sound waves. Once the glass vibrates so hard that it essentially can’t vibrate any longer, it will shatter or crack throughout.
The bass that comes out of a subwoofer differs greatly from the sounds that come through regular speakers.
You can listen to bass with the volume up to 100db and the music would probably hurt your ears from the other speakers before the bass would. You could technically crank the bass up so much that it would shatter a nearby window. However, it would be so outrageously loud that your ears would throb and you would have trouble breathing.
That’s not to mention that the other speakers would be playing at decibels loud enough to have the entire neighborhood gather at your front door.
As a side note, if you’re worried about putting your sub on a TV stand with glass shelves; the subwoofer doesn’t actually have to be positioned close to the TV. The low-frequency sound from a sub is not directional so it does not need to be facing you or even close to you to sound good.
You could do a subwoofer crawl to find a number of good spots around the room.
Could A Subwoofer Break A House Window?
Of all the glass a subwoofer could potentially break, it would probably be a house window. They usually aren’t as strong as other window types and, unlike wine glasses, they aren’t shaped around a hollow point, which gives the glass a kind of fallback point.
It’s surprisingly hard to do so, however. Mostly, it’s because house windows are in large rooms, which provides the soundwaves with some room to breathe.
You would need to set the subwoofer up so that it is facing the window, an inch or two away.
Then you would need to crank the thing all the way up.
By the way, if you ever do this, it’s highly advisable to turn all of the other speakers off. The subwoofer would have to reach a high enough decibel to overcome the glass’ vibration and it would have to do so before the sub itself blew.
You would probably need a little help too—something like the window pane not being completely sealed right so that the vibrations of the glass change to a degree.
No matter what you decide to do, you will find that it’s a lot harder to break glass with a sub than you think.
Related Article: Can A Subwoofer Be Placed On A Shelf? (Explained)
Could A Subwoofer Break A Car Window?
It is possible for a subwoofer to break a car window but only in extreme situations. Normally, it would be even harder for a subwoofer to break a car window than it would a house window. This is true because car windows are designed to be more robust.
If you search YouTube for ‘subwoofer break glass‘ you will find videos of car windows breaking from the intensity of the bass being played. But these are the most extreme sound system setups, usually for competitions, and sometimes the windows that blow out look like they have gone through a fair bit of wear and tear beforehand.
There are also videos on Youtube of people running over 10,000+ watt Sundown systems that make objects dance on the dashboard and the exterior of their cars physically vibrate but you still won’t see a window break.
Car windows are typically reinforced and laminated. It’s a safety feature that keeps the glass from shattering all over you in the event of an accident, reducing the likelihood of you or someone else getting a serious cut.
The front and rear windshields are actually two layers of glass. Both of these layers are fused using vinyl that’s sandwiched between them. Also, the windshields in your car are designed with different materials than what you will find in a household window.
Vehicle windshields are a combination of a few or several of the following materials:
- Soda Ash
- Cullet
- Limestone
- Dolimite
- Silica Sand
Once the materials are melted together to form the pane and multiple panes are fused together, you end up with far stronger glass material. On top of that, they laminate the window pane before installing it on the car.
At the end of the day, your subwoofer is not likely going to have enough oomph to blow out your vehicle’s windows. If it were capable of getting loud enough to crack your windshield, you had better be far away or you’ll never hear again.
Could A Subwoofer Break A Glass Shelf That It’s Placed On?
A subwoofer could possibly break a glass shelf by causing it to vibrate off the wall. However, this would be due to the subwoofer unit vibrating and not the glass shelf vibrating at its natural resonance.
Again, this is a case of the sub’s frequency needing to match the resonance frequency of the glass that it’s sitting on to cause it to shatter. Not to mention the fact that the subwoofer should be sitting on the glass, facing forward and away from the glass it’s sitting on at a 90° angle.
It’s possible that the sub could get loud enough that its own vibrations shatter the glass beneath it. However, that’s not quite the same because it would technically be an impact break rather than the sound emanating from the sub breaking the glass.
It’s often recommended that you place something underneath a subwoofer to absorb the vibrations that it creates within itself. You should do that regardless of the surface that it’s sitting on.
One of the most highly recommended materials to put underneath a subwoofer is called an isolation pad. Isolation pads are made out of spongy, rubber material that is really good at absorbing the vibrations that a subwoofer creates.
The isolation pads effectively dampen the vibrations from the subwoofer and keep it from shattering the glass or damaging any other type of material that you might set it on.
Do Isolation Pads Reduce the Bass Effect?
Isolation pads will indirectly affect the best that your subwoofer’s bass has to offer but only to a small degree. If you have a really expensive system, it would probably be more noticeable. With a standard, surround sound home theater system, you may not notice as much.
One of the best things that you can do with a subwoofer is set it at eye level and in the center of the room. All of the other speakers belong on glass shelves throughout the room but a subwoofer is at its best when it’s sitting on a wood, elevated platform that places it level with your head while you are watching or listening to music.
All Things Considered
It’s highly unlikely that your subwoofer is going to wreck any of your glass, especially before it becomes too painfully unbearable to listen to. Subwoofers emit a low enough frequency that it’s not likely a match for the resonance frequency of the glass around them. So turn your bass up as loud as you want—your glass should be just fine.
