The Sealed Box Subwoofer Enclosure is the easiest to design and build, and provides the most accurate bass and a linear response curve. Translation: High end sound quality. There's a price, though - sealed boxes are not as efficient as ported boxes. Let's consider:


Advantages:

• Sound quality is best because box helps amp control speaker cone accurately
• Predictable, smooth response curve lacking any "hot spots" that ruin listening experience
  
• Typically sealed sub enclosures require a smaller box size than a ported design
• Construction and design are simple and straightforward

Disadvantages:

• Response is diminished by 3db or more over a ported box design
• Cannot be tuned to optimize driver response as in a ported design

The sealed subwoofer enclosure design is best suited to classical, rock, country, and other types of music where extreme low end performance is not as important as snappy, tight pounding bass. It is also ideal in situations where the best sound quality is desired.

Because the sealed sub box design dampens speaker excursion, it allows you to use an amplifier output near the maximum rated power input of your subwoofer. Since it does not rely on moving a specific mass of air for optimal performance, a sealed subwoofer enclosure generally can be smaller than a ported enclosure. For a given subwoofer, the optimum box size for a sealed enclosure is typically 2/3rds the vlume of a ported box.

Use a sealed box subwoofer design in systems with ample amplifier power for the subwoofer, where space or sound quality are of primary concern, or when ease of construction is desired.



Typical Sealed Enclosure Volumes for Common Subwoofer Sizes

6.5-inch Subwoofer Driver
ranges from .1 cu ft - .6 cu ft

8-inch Subwoofer Driver
ranges from .2 cu ft - 1.0 cu ft

10-inch Subwoofer Driver
ranges from .2 cu ft - 1.75 cu ft

12-inch Subwoofer Driver
ranges from .5 cu ft - 3.0 cu ft

15-inch Subwoofer Driver
ranges from 1.5 cu ft - 6 cu ft

Freeware Subwoofer Enclosure Design Software Tools

Designing the optimum stereo system for your car stereo or home theater system requires an optimally designed subwoofer enclosure.

While this can become complicated, fear not - several freeware applications are available to help you design the right enclosure for your application.


Whether you've already decided on which subwoofer speaker drivers to buy or not, these tools will help you make the most of your subwoofer purchase. If you've become overwhelmed with trying to decide what speaker will work best for your application, try this: Download the application that applies to the type of enclosure you've settled upon (not sure? See articles at right).

Try plugging in the specs for Qts, Vas, Fs, and Pmax for several of the subwoofer drivers you're considering. See how the different drivers perform in the type of enclosure that fits your type of music and space requirements. This should help narrow the field to the two or three subwoofers that will fit your unique combination of factors.

Ported (Vented) Enclosure Design Program - this handy freeware application allows you to input speaker parameters such as VAS and QTS, available from any reputable subwoofer manufacturer's website and many subwoofer dealers' websites, and calculates the frequency response and output curves for your amplifier power. It also calculates the ideal box volume and port length. Then, using the box design tool, you can calculate the dimensions of the box using that data to design the right ported sub box for your application. Extremely useful, and completely free!

• Download freeware ported sub box designer

Sealed Enclosure Sub Design Tool - As with the ported box designer above, this tool accepts data about your subwoofer, and outputs specifications for the ideal sub enclosure. This program is used to design sealed subwoofer boxes.

• Download freeware sealed sub box designer

Bandpass Subwoofer Enclosure Design Software - Again, this freeware subwoofer enclosure design program takes data about your sub as with the tools above - but this program allows you to design more complicated band-pass subwoofer boxes.

• Download freeware band-pass sub box designer