If it’s your first time setting up a subwoofer, or you’re wondering how to set up a subwoofer for the best bass output, you may be confused between selecting subwoofer phase 0 or 180. While it’s possible to adjust bass level and volume to your liking, it might be confusing to know the ideal phase for your sub. Thus, it’s important to learn what phase control is and how to set it properly. In this article, we’ll guide you on which is better between phase 0 and 180.
What is Phase Control?
Phase control is a common feature in powered subwoofers. Essentially, phase control makes it possible to introduce an electrical delay to an incoming audio signal. You can set phase control between 0 to 180 degrees. Sometimes, introducing delay to the sub signal assists the sub to integrate efficiently with other speakers in the room. If you fail to set the phase properly, the subwoofer will be out of sync with other speakers in the setup.
The way you set the phase mainly depends on the subwoofer placement in the room. You simply adjust the phase control using the phase switch on the subwoofer. If the sub is out of phase depending on its position in the room, you won’t feel its bass output. Also, when the speakers in a room are out of phase, you will feel that bass from one speaker overshadows bass from other speakers.
How Does Phase 0 Differ from Phase 180?
When selecting phase control, you can choose either subwoofer phase 0 or 180. How do they differ? Let’s find out.
Phase 0 Explained
Phase 0, also known as the normal phase, means that there’s no delay on the incoming subwoofer signal. By setting the subwoofer to phase 0, it means that the subwoofer and speakers in the room are in one phase. So when should you set your subwoofer to phase 0? Well, phase 0 should only be set when the subwoofer and speakers are placed in the same direction and within the same area.
Phase 180 Explained
Phase 180, also referred to as the reverse phase, means that the subwoofer polarities get reversed. By setting your subwoofer to phase 180, you reverse its polarities to that of the speakers in the same room. Essentially, the subwoofer driver will move inward whereas the speakers’ drivers will move outward. So when should you set your subwoofer to phase 180? Phase 180 is best set when the subwoofer are and speakers are placed on opposite walls.
When the subwoofer and speakers are positioned on opposite walls, there is no interference with their sound waves. Thus, there’s reduction in interference. However, phase 180 reduces the overall bass output.
Fortunately, some subwoofers come with variable phase control. In this case, you can adjust the phase level in certain increments. That way, you can set a more accurate phase level for improved bass output and performance.
How do You Choose the Best Phase Setting for Your Subwoofer?
When setting the phase control, you will need to consider the sound quality and subwoofer placement in the room. Most importantly, set the phase control to the level that the subwoofer and speakers sound best. Try different phase settings until you hear the one that sounds better.
Also, consider the subwoofer placement. If you have placed the subwoofer alongside the same wall as the speakers, set the subwoofer to phase 0. That’s because the drivers of the speakers and subwoofer are facing the same direction for harmony between their bass outputs.
On the other hand, if the speakers and subwoofer are positioned on opposite walls, their drivers are facing each other. Thus, you should set the subwoofer phase to 180 to prevent their bass output from canceling each other.
However, other factors may influence the sound output. Thus, your priority on setting the subwoofer phase should be determined more by the sound quality rather than the subwoofer positioning.
Setting up Subwoofer Phase 0 or 180
You’ll need to use the phase switch to set the subwoofer phase. If the subwoofer only has 0 and 180 degrees phase, you can only switch between the two. On some subwoofers, the phase is variable such that you can use a digital switch to make the adjustment in small increments.
When making phase adjustments, keep the volume low to get more accurate results when listening. Preferably, play music with heavy bass when adjusting phase. Upon adjusting the phase to one level up, increase the volume a little. Listen to the bass output from the same sitting position throughout the increments. Continue making adjustments while listening until you hear the best sound quality.
Choosing subwoofer phase 0 or 180 is all about the positioning of your subwoofer and speakers and the kind of sound quality you get. Just experiment with the two options until you find the one where the bass output sounds best. Remember that setting up your subwoofer and speakers is all about balancing the overall sound output.
Michael Evanchuk is a San Francisco-based sound engineer with 20 years’ experience installing, troubleshooting, and repairing commercial, automotive, and household sound equipment. Evanchuk owns an auto stereo center, where he offers highly competitive car audio installation and repair services. He has written dozens of articles on different sound engineering topics, all of which have been published in leading journals, blogs, and websites.