Subwoofer Box Information For Beginners
There are many different types of boxes you can use to mount your subwoofers. I will be going over the different types of subwoofer enclosures options that you have.
Infinite Baffle | Free Air
This is going to be the easest and cheapest way to add a subwoofer to your car audio system. This setup is tipicaly done in car with small trunks and there is not very much space available. There are a few ways that this can be set up. The car subwoofers can be mounted in a large cars rear desk or behide the back seat. Basically you are using the trunk as the speaker box in this set up. Now you must make sure that the truck is completely sealed off from the rest of the car to prevent cancellation.
Sealed Enclosure | Isobaric
This seams to be one of the most popular enclosures used in SPL competition because it produces great low level power handling and require less space than most other speaker boxes need. The sealed box is the most forgiving to design errors. Now a couple of he cons of sealed boxes. You may notice more distortion at high frequency and the speaker magnet will not cool as easily as non sealed boxes. Now even though sealed boxes require the least amount of space if you have even less space than need for you sealed box for a give subwoofer you can use the Isobaric setup. This setup requires less air space in the sealed box but takes two subwoofers to get the output as if you had the one subwoofer in the correct sealed box. Isobaric is when you have a speaker mounted in a sealed box like normal but also mount another subwoofer to the first face to face.
Vented | Ported Boxes | Bass Reflex
If you are going to be making your own box, the bass reflex boxes are not nearly as forgiving as the sealed box and you will hear you design mistakes. The bass reflex or ported box is basically a sealed box with a port or vent tuned to a specific frequency. This setup has good power handling and excellent efficiency. Now the down side of the Ported box. The ported boxes can be much larger than sealed boxes. Playing a subwoofer below the tuned frequency and power handling will produce a very poor sound and will damage the subwoofer. Do not lower the port below the manufacturer’s recommended frequency, this will only make things a lot worse.
Bandpass
The most popular in SPL competition. A bandpass box is basically a port box with another enclosure mounted to the front of it with another port or vent. When built correctly will produce very high SPL. But here is the problem. Bandpass box are not for giving at all. If the box is not built correctly it will a total waste of time and money and sound horrible. Bandpass boxes have to be tuned for a narrow bandwidth of frequency response. Suboofers are susceptible to cone over-excursion for frequencies outside of the tuned frequency response, and even worse if below. Please make sure to use a very good crossover to keep the frequency response in the correct range.
Related posts:
I know sealed boxes are supposed to be made to the dimensions specified for the speaker, but what happens if you put a speaker in a box with dimensions too big or too small? Would it be just sound quality issues or physical damage?
I have 2 infinity kappa perfect 12 inch subwoofer and personaly its the best sub i ever had in my life. Its loud with quality. The only thing is that you need a good amp to drive them.