Finish off your car audio with a subwoofer

Low frequency sounds are the main component of good sound. The quality of a sound system depends on its ability to reproduce both low and high notes. Some types of music benefit from a large subwoofer more than others, but adding quality bass into the stereo system brings the music to life.

If you are thinking about adding a subwoofer to existing speaker installation or building something from scratch, here are some important details to keep in mind.

Close subwoofer kicker — null0 / Flickr / CC BY 2.0

Size matters

The size of a subwoofer is one of the main factors in determining how loud and low it can be. Generally, larger subwoofers produce better bass, so keep that in mind when looking for the perfect unit.

Space is also a problem in car audio systems. It is very important that you take measurements of your available space before you start shopping. If you’re looking for the most daring bass you can get, then choose the biggest subwoofer to fit your car.

Sound capture in the body

While the size of the subwoofer is important, the type of enclosure you choose can have the biggest impact. The enclosure, commonly referred to as the box, is simply the box containing the subwoofer. Three main body types:

sealed
Ported
stripe

If you want exceptionally deep bass without sounding like your subwoofer farts , select sealed housing. In some cases, a smaller subwoofer in a well-built, sealed cabinet will produce deeper bass than a larger subwoofer in an open cabinet. This type of body is great for tight, precise bass that doesn’t wobble your fills.

Ported and striped cabinets tend to be louder, but not as deep. If you listen to music that requires very loud bass and you don’t really care about low end accuracy, consider one of these cabinets.

Another option is to choose a subwoofer that is designed to work without a cabinet. These subwoofers are usually mounted on a board installed inside the trunk. The barrel must be relatively airtight because it acts as a de facto hull.

Power, sensitivity, frequency and impedance

While subwoofer size and cabinet type are important, you need to pay attention to RMS, SPL, frequency range, and ohms.

The power level (RMS) refers to the power management characteristics of the subwoofer. The higher the RMS value, the more bass. However, a high RMS value is useless without power, so you will need head device or amplifier, which matches (or preferably exceeds) the RMS of the subwoofer.

Sensitivity, which is expressed as a sound pressure level (SPL) number, refers to how much power a subwoofer needs to produce a given volume. High SPL subwoofers do not require as much power to produce loud sounds as low SPL subwoofers. This means you will need a high sensitivity subwoofer if your amplifier or head unit is not powerful enough.

Frequency refers to the range of sounds a subwoofer can produce, so look for one at the bottom of the scale. However, the sound you get from a subwoofer depends on the type of cabinet you choose. Because the enclosure can modulate the sounds that reach your ears, the subwoofer’s frequency numbers may not accurately reflect the actual operation of the subwoofer.

To get the most out of your amplifier and subwoofer, it is important to choose impedance . This figure is expressed in ohms and refers to the electrical impedance of the subwoofer. The low impedance means that the speaker can receive more electrical signals, thus improving sound quality. As a concept, impedance is relatively simple, but it gets more complicated depending on how the subwoofer is wired, or if it has multiple voice coils, among other variables.