Subwoofer Box Types
Subwoofer enclosures do more than just give you somewhere to mount your subs; they also play a huge role in the bass produced by your subwoofers. Choosing the right enclosure can be tricky, but we are here to help relieve some of that confusion and get your foot planted firmly through that car door. There are three main subwoofer enclosures types to consider: Sealed, Ported/Vented, and Bandpass enclosures. Each has advantages and disadvantages in efficiency, size, distortion, cost, and power handling. The different enclosure types produce a unique sound and choosing an enclosure should be based upon the music style you listen to. Here is the rundown on the various enclosure types:
|Sealed Subwoofer Box|
The sealed subwoofer enclosure is characterized by excellent transient response(less boom, more punch), superb low frequency power handling, and a smaller box size. When a speaker is mounted in a closed box, the air in the box acts to some extent as a spring. However, sealed enclosure systems tend to suffer from higher cutoff points and lower sensitivity than the other low frequency systems. They are usually the subwoofer system of choice for audiophiles because of their excellent transient response. The box internal volume should be as close as possible to what is recommended by the manufacturer. If a box is smaller than what it is recommended, the sound will be tighter, but more amplifier power will be required to push it.
If the sub box is too big, then the sound will be filthy and distorted.
Overall it produces a crisp and clean sound for any type of music. If you did not understand what any of that meant, here is a basic run down:
- Less Boom, More Punch
- Top Choice for Audiophiles
- Smaller Box Size Required
- More Amplifier Power Required
A ported enclosure system consists of a driver mounted on one side of a box that has an open tunnel or port which allows the passage of air in and out of the box. The function of the port is to "tune" the enclosure so that the rear wave of the speaker enhances the front wave of the speaker. This typically results in a woofer system with a higher efficiency (it plays louder with less power). At low frequencies, the vent contributes substantially to the output of the system. The box design acts as a filter, cutting off lower frequencies.
|Ported/Vented Sub Box|
Distortion rapidly increases below the cutoff frequency as the sub loses load. The transient response of a ported enclosure system is usually inferior to that of a sealed enclosure system using the same sub. Let’s rehash the main points of a ported/vented enclosure:
- Equal Boom, Equal Punch
- Strengthens Bass
- Amplifies Sound
- Bigger Box Size Required
Enclosures consist of a woofer between a sealed and ported box. Bandpass boxes will yield more bass than sealed and ported boxes (especially at lower frequencies), but over a narrower frequency range.
Since the box acts as a filter, mechanically blocking lower and upper frequencies, a crossover is not needed in most cases. These enclosures are usually big and very unforgiving when precise volumes and port sizes are not followed. Bandpass boxes also tend to mask distortion which could lead to damaged subs. Bandpass enclosures are extremely efficient in the band of frequencies that they are tuned to or "pass" (hence the term bandpass). Disadvantages of this design are a limited frequency range, huge enclosure size and limited power handling. We don’t recommend any more than 500 watts RMS power to a bandpass enclosure.
Let us take another look at the main points:
- Lower Bass Frequencies
- Should Be Tuned
- Low Power Handling
- Biggest Box Size Required
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