Are Two Subwoofers Quieter Than One?
One piece of advice we’ve been seeing popping up more and more is about keeping your subwoofer from bothering your neighbors. We’ve written about how to stop sound from bothering those who share a wall with your space. One thing that wasn’t common was a recommendation to get a second subwoofer. The idea is that two subwoofers are quieter than one. Is this true? Will it work? Let’s discuss!
Quick Answer: No
There are a lot of reasons why people might think that having multiple subwoofers is somehow quieter than having one (we’ll address these below). The short answer to this question is no. One subwoofer is not somehow louder than two. When your room correction sets your distance and levels, it calibrates your subwoofer or subwoofers for the same volume level. It doesn’t matter if you have one subwoofer or ten. The trim level will be set so that it outputs the same volume.
Why People Think One Subwoofer is Quieter than Two
There are a lot of reasons why people might think that a single sub is louder than one subwoofer. The big reason is room acoustics. The single subwoofer will often have huge peaks a dips that creates a very uneven bass response. When the content calls for bass where your response is at a peak, it sounds very loud. One would describe it as artificially loud. Two subwoofers will sound quieter in comparison because of a more even bass response. There won’t be peaks in the response where there shouldn’t be. Instead, there will only be bass when you expect it. The reality is that your room correction will consider that peak when it sets the trim level. The rest of the bass will come out quieter by comparison.
Where the confusion generally lies is in the trim levels. When your room correction sets your trim levels for a single subwoofer, it will (likely) be higher than the trim level for each of the two subwoofers. When the one subwoofer trim level is higher than each of the trim levels for the two subwoofers, people will think it will give a quieter experience.
That’s not the case.
As both of your subwoofers are creating the same sounds, the overall volume will be additive. As a general rule, adding a second subwoofer to your room will increase the overall output by 3-6dB depending on where they are in the room. Looking at the trim levels of your subs and thinking that them each being lower would equate to less bass in the room makes sense. But it isn’t the way it works.
Take Away
The best way to keep bass from traveling from one room to another is by decoupling your subwoofer or subwoofers. Adding more subwoofers won’t make a significant difference.