Should You Toe-In Subwoofers
When you place your speakers, you often worry about toe-in. Toe-in is how much you angle your speakers toward your listening position. With some speakers, you can place them straight forward and they sound great. Others need to be pointed directly at you (very few) for best performance. Most are somewhere in-between. So, if we are worried about toe-in with speakers, should we also be worried about toe-in with subwoofers?
The Science of Bass
Bass waves are extremely long. The lowest bass produced by your subwoofer is up to 55′ long. This means that as the driver in your subwoofer produces the bass wave, the wave wraps all the way around the subwoofer cabinet. It looks like this:
In the image above, there is a boundary (wall) behind the subwoofer that would reflect the sound. In an open room, with no walls, the sound would emanate from the subwoofer in a spherical shape.
Your Room And Bass
It is unlikely that your home theater room or area is 55′ in any one dimension. This means that the sound the subwoofer makes will hit and reflect off of every wall in your home theater at least once (sometimes multiple times) before a single wave can register in your ear. This means your room “hears” the bass long before you do. Your subwoofer isn’t “beaming” bass sounds at you like your normal speakers. Instead, you are hearing reflected sound from your room coming from many directions!
Will Toe-In Make a Difference?
If the sound is coming from your subwoofer in all directions, and you are hearing nothing but reflected sound, it is clear that the angle of your subwoofer won’t matter one bit. If you are looking for more evidence, there are plenty of subwoofer manufacturers out there that will sell you a subwoofer that has a front-facing driver and say they can be paired with another of their subs that have a down-facing driver. Check out the image at the top of this article. These are the 2000 Pro series of subwoofers from SVS. They often rate the PB and PC (ported box and ported cylinder) subs exactly the same. Clearly the direction the driver faces really doesn’t make a difference.
What About Boundary Reinforcement?
“Okay, smart guy,” says you, “so I can just push my subwoofer into a wall with the driver facing the wall and nothing will happen? What about that boundary reinforcement you are always on about?”
Sure, it isn’t recommended to place your subwoofer driver directly against the wall. But, honestly, as long as you aren’t impeding the driver’s extension (how far out the driver can travel), you are unlikely to hear a difference. There are some rooms where placing the sub so that it is firing into a corner can have sonic benefits.
So, there you have it. You don’t need to toe-in your subwoofers. But if you want to angle them because of aesthetic concerns or just because you think they look cool, have at it!
What about you? How have you placed your subs? Let us know in the comments below.