the tools you will need
You need some basic tools to mount your subwoofer in a box and connect it to your system. At a minimum, you should have the following tools on hand before you begin:
basic subwoofer installation
Subwoofers are specialized speakers that reproduce low notes. they are a popular component in many audio systems because they produce strong, deep bass. they also make your other speakers more efficient by deflecting the notes that full-range speakers struggle to reproduce.
Reading: How to connect subs to car
Subwoofers come in a variety of sizes and shapes. the most common type is an unpowered component subwoofer. This subwoofer does not have a built-in amplifier as a power source, so you will need to connect it to an external amplifier to draw power. (Some subwoofers have built-in power supplies. See page 3.) Also, while some subwoofers can be used without a separate enclosure in space-saving outdoor installations, most require a sturdy enclosure to function properly.
The most basic element of component subwoofer installation is very simple. mount your component subwoofer in a suitable box by connecting the wires to the terminal cup and using mounting screws. It shouldn’t take more than a few minutes. then run the wiring to a nearby amplifier. You will have options on how to connect your subwoofer. you can connect in parallel for maximum output, or in series for a higher impedance multi-woofer setup.
Built-in subwoofers are the easiest way to get better bass, because the manufacturer has already built the box and installed an appropriate speaker. some prefabs have up to three subs in them. you choose the style and size you want and match it with your amplifier, your available space, and the rest of your system.
In sedans, off-the-shelf unamplified subwoofers usually go in the trunk. if you’re giving it the right amount of power, the bass it produces will be strong enough to penetrate through the backseat. simply connect the speaker cables from the amp and secure the box with straps or brackets. make sure you don’t block access to the spare tire, and if you drill holes for the brackets, work carefully and make sure you don’t cut into the gas tank or a brake line.
If you’re installing a subwoofer that comes with a built-in amplifier, you won’t have to connect the speaker cables, but you will need to install a patch cable (or connect the speaker cables for the input signal). you will need an amplifier wiring kit for the power, ground, and power wires. Usually, that means running cables under your seats.
Powered or amplified subwoofers offer an ease of use that comes in handy if you drive a rental or leased vehicle. Due to their portability, these replacements can be quickly removed if you sell or trade in your vehicle. they also take up less space than a separate amplifier and subwoofer.
Use extreme caution when anchoring a subwoofer in a hatchback, pickup truck, or sport utility vehicle. it could fly away and injure someone if it stops suddenly.
prefab sub enclosures
While pre-built subwoofers have their advantages, you’ll have a greater variety of subwoofers if you opt for a component subwoofer and proper enclosure. it’s more work, yes, but you can create the sound you want. you choose the subwoofer or subwoofers that best suit your musical needs, and then select the cabinet size that will optimize its sonic properties. Most component subwoofers don’t come with hardware, so you may need to provide your own screws. In addition, you may need speaker cables and accessories to connect the speaker to the terminal cup on the box. finally, find some brackets or straps to hold the cabinet in your vehicle.
wiring and theft
If you’re going for the most common type of subwoofer setup (a component subwoofer in a box connected to an amplifier), you’ll need to consider several wiring possibilities before you begin.
A 2-channel amplifier gives you outputs for two speakers. Of course, that doesn’t mean you have to connect two subwoofers. you can connect one, two or even four. to be sure, you only need to consider the impedance of your subwoofers and the “load” capacity of your amplifier. these factors will determine which wiring method you should use. For more information, check out our collection of subwoofer wiring diagrams.
typically a car stereo amplifier “sees” an impedance of 4 ohms. when we say an amplifier is stable down to 2 ohms, we generally mean the minimum impedance it can drive in stereo (2-channel) mode, not bridged (mono) mode. the lower the impedance (resistance or “load”) an amplifier sees, the more power it produces and the louder the music sounds.
A common way to get a stable 2 ohm amp to produce the extra power it offers at a lower impedance is to connect the speakers in parallel. remember: while wiring in series always increases the impedance, wiring in parallel always reduces it.
To connect the speakers in parallel, connect the positive (+) cables of both speakers to the positive (+) terminal of the amplifier and the negative (-) cables of both speakers to the negative (-) terminal of the amplifier. You can dramatically increase the impact of your system by connecting two subwoofers (in parallel) to each of your amplifier channels.
After completing the wiring, install your subwoofer correctly. play the subwoofer at low volume for about 20 hours to condition it before turning up the volume. this will improve the performance and life of the subwoofer.
building your own subwoofer box
A box does more than just hold the woofer; it is an integral part of the system. a properly constructed and sized enclosure can turn an inexpensive woofer into a good performer, while a poorly designed or constructed enclosure will make even the best woofer sound horrible.
There are two main challenges in building a cabinet: making sure it contains the right volume of air, and controlling cabinet resonances that will otherwise compete with the sound of the woofer and color your sound.
The ideal cabinet volume (length x width x height) will vary depending on the woofer you select. The cabinet volume of your subwoofer is usually indicated as the internal volume. therefore, when calculating the overall external dimensions of the enclosure, you must take into account the thickness of the plate, the space occupied by the speaker, and any internal bracing.
Once you know the internal volume you want to achieve, you’ll decide on the dimensions of the enclosure. As a general rule, make sure that no internal dimension measures more than three times that of any other. but don’t get them too close together or you’ll get a cube, one of the worst acoustic shapes for a speaker.
so keep these two rules in mind: don’t make one side much longer than the other and don’t make them too close together. almost any shape will be fine. it is the volume that matters most.
Finally, determine if your box will be sealed or ported. a sealed enclosure is the easiest to design and build, and it protects the woofer from subsonic bass that can affect its performance. A ported box uses a tube (port) that reinforces the bass produced by the woofer. it can deliver excellent high-performance performance, but is more difficult to build.
for more information on the subject, check out our article on how to build a subwoofer box.