Subwoofers, or subs, as they are commonly known, are are what everybody wants these days.

There are many different subs available on the market and different sizes do different things.

Subs come in many different sizes, from 8" to 15 and 18. The common shape is, of course, round, but Kicker has their square SoloBarics, and Sony has their new pentagon subs.

The smaller, 10's and 12's are better for music that needs a tighter bass sound. For example, techno and rock would be good on these subs. However, subs that are of this size are not very good at lower frequencies and distort.

This is where the larger subs come in. They are able to hit lower frequencies and hold it, however they cannot hit tight beats that 10's and 12's can.

Also, it is the larger subs that can be heard from a long distance. Two 12's can be heard farther than two 10's, however, IN the car itself, the two 10's will hit harder.

There are even more factors which may affect your decision:

• What kind of music will you be listening to?
  Will you be entering into sound-off competitions?
• What is the resistance presented by the subs?
• How much are you willing to spend on the subs, and amp(s) to power them?

If you are going to be listening to rap, then some 12's or 15's will be good, and SoloBaric's will work too. However, if you want a tighter sound, such as techno, 10's or even 12's will be fine. SoloBaric's, on the other hand, are known to be good only for SPL, and not good for sound quality.

The resistance presented by the subs has more to do with your amplifier than with your subs themselves. The lower the resistance, the more power that the amp will be putting into the subs, however, too low and the amp will fry. Note that the way that you wire the subs will affect the resistance. Wire them in parallel and it will split the load, and wire them in series and it will add the loads. For example, two 4 ohm subs wired in parallel will make 2 ohms, however if you wire the same subs in series they will present 8 ohms.

And finally, of course, the more you spend on the subs, the more powerful, clear, and high quality they will be.

Now, after you have purchase your subs, you will have to decide what kind of box to put them into.

A sealed box provides a tighter sound, but requires more power and is not as loud as the other boxes.

A ported box's sound is not as tight, but it will pound louder and is better for SPL competitions.

There are also other types of boxes available that i will not go into details about.

A good program to download for calculating the size of the box required for the subs, WinISD, available for download here.

Some of my favourite brands of subs are as follows: Alpine, Rockford Fosgate, Kicker, JL, Infinity, and Phoenix Gold.

Again, just as with all other car audio components, go and listen to the subs before you purchase them.

I would suggest either getting professional installation with a custom made box and good quality wiring, or, for the do-it-yourselfer, you can use the program above to help design a box for the subs, and then purcahse a sub wiring kit from your local electronics store.