As part of our recent focus on subwoofers and making better bass, we asked last week how many subwoofers you have in your home theater. Now I’d like to know what type of subs you use: sealed, ported, or cylinder?
If you’re not familiar with the differences between these types of subwoofers, I unfortunately don’t have the time to write a detailed article about it here. The short version is that ported subs are able to displace more air than sealed subs, and thus can hit deeper octaves at louder volumes. This makes them very well suited for viewers who really want the bass to slam them in the gut during a movie explosion. The trade-offs to this, however, are: 1) Ported subwoofers are physically much larger than their sealed counterparts, and thus are harder to place and eat up a bigger chunk of room space, and 2) Ported subs frequently have a steeper drop-off curve than sealed subs and may sound boomy.
Music aficionados have often argued that sealed subwoofers have a “tighter” response that reacts better to quick changes in musical tempo, and a shallow drop-off in the bottom end that sounds smoother. However, this is a not-entirely-accurate simplification. A well-designed and -engineered subwoofer of either type needs to be able to strike a balance between both music and explosions, and those from the best manufacturers manage to do that.
Cylinder subwoofers are typically ported in design, and offer the air displacement advantages of a ported sub while taking up fewer square feet. They can be pretty unobtrusive when placed in a corner. On the other hand, their taller height usually rules out putting them in the front of the room between the main speakers, because they’d block the viewing screen there.
Personally, sealed subwoofers are the most practical for me. I have a decent-sized but not huge home theater, and with all my equipment and furnishings simply don’t have any good space to put a big ported sub. I don’t think a cylinder would work out very well for me either. The only corner I have free where I might put a cylinder sub is not a very good acoustic position for a subwoofer. That doesn’t mean I have anything against ported or cylinder subs, just that the decision hinges on very pragmatic concerns in my room.