One or two subwoofers in a vehicle can make a world of difference in listening to music. It is very important to match the RMS of the subwoofers to the amplifier. It would be better if the amplifier is more powerful than the sub, because you don't want to activate the sub's clipping function. Clipping is the number 1 cause of subwoofer death.
Steps
Step 1. Gather the material (amplifier, subwoofer, stereo and wiring)
You can find a wiring kit in many stores, with 5mm wires and an inline fuse. You don't need a cable wider than 5mm.
If you are using an aftermarket head unit, go to an electronics store, the stereo department and request a wiring harness that goes from the car to the aftermarket head unit. For example, if you have a Chevrolet and a Sony stereo go to the store and say you need wiring that connects the Chevrolet to the Sony; they will ask you what year the vehicle is from and then they will go and get the harness from the shelf it is on, which is usually behind the cashier. Once you have purchased the harness unscrew the factory stereo, unplug it and connect the new harness, one end to the car and the other to the new stereo. When buying new wiring make sure it matches the model and size of the stereo
Step 2. Run the amplifier cables (up to the battery, through the bottom)
Figure out where you will place the amplifier, put the power cable (red) there and give it about 12 inches of extra cable, then start hiding and running the power cable under the hood. Some vehicles may have pre-existing cracks saturated with a plastic / rubber insert. Run the power cord through the fire bulkhead. If you need to drill a hole in the fire bulkhead, be careful not to hit anything on the other side and make sure the hole doesn't affect the power cord. Applying electrical tape to the entry point will give the cable additional protection. Make sure this cable is safe from any moving objects.
Step 3. Unplug the car power cable from the battery and attach the amplifier power cable to it; do not reattach the car cable to the battery
If you bought a kit, it comes with an inline fuse; if you haven't received it, you will need to get one. Simply cut the power cord, insert the fuse in line and reattach it. The amperage of the fuse should match the diameter of the cable.
Step 4. Place the amplifier wherever you like, then connect the ground wire (black or brown) to the amplifier
Ground it with a piece of bare (unpainted) metal; most people unscrew a bolt from a seat, connect the cable, and screw the bolt onto it. Lightly scrape the contact area to expose the bare metal of the bolt prior to grounding.
Step 5. As for the RCA jacks, if you are using an aftermarket stereo on the rear there are two RCA jacks
Simply slide the jacks from there to the "IN" input on the amplifier and try to prevent the RCA jacks from sliding next to the power lines to minimize noise.
Step 6. If you are going to use the factory stereo and run the amplifier from there, you will need to buy a Line Out converter
Together with the converter you will get a small box with two RCA outputs on one side and an output for 4 speaker cables on the other. You should take the speaker out of a hatch and run 2 of the 4 speaker cables to the box, paying attention to the positive (+) and negative (-) poles. You don't need the other two cables. From here you pin the Line Out connector out of sight and run the RCA cables to the amplifier, connecting them to the "IN" input of the RCA jacks.
Step 7. Now let's think about the remote cable (the blue one)
If you are using an aftermarket stereo there will be a blue wire located in the rear harness; mostly these cables are fixed, so you will have to join them together. Simply cut them, seal the used end and run the remote cable to the amplifier. If you are using the factory head unit you need to purchase a two position switch that suits your "whim". Find a cool place to mount or hide it, from which you will attach the remote amplifier cable, sliding it into the switch. Cut it, connect it to one pole, then connect the end you just cut to the other. Then run the remote cable behind the amplifier and cut it to leave about 12 inches or more of extra cable. This will come into play later.
Step 8. Use a capacitor to prevent voltage drops, such as dimming the light with the rhythm, caused by deep, low blows
Place the capacitor as close to the amplifier as possible, and use grounding as you did for the amplifier. Test the power cable and find out where the capacitor ends up, cut the cable and attach the cable for the battery to the battery. You can't just connect it; you must first load it with a resistor. Use a 1000 ohm resistor because these do not heat up. Take a few seconds to charge, and don't do the operation with your bare hands. To ground the capacitor, grab a voltmeter and place it on the capacitor itself; take the resistor and place it on the power side of the capacitor. Connect the power cable to the other end of the resistor, the voltmeter will jump around 12 volts, so the capacitor will be charged.
Step 9. Slide the power cable to the amplifier
If you have a factory stereo and have the remote cable there, you should string the remote cable with the power cable before inserting it into the amplifier's power slot. The remote cable commands the amplifier to turn on; so, if you don't have the aftermarket head unit remote cable to turn on the amplifier, every time you turn on the stereo you will have to turn on the amplifier manually. Make sure you always turn off the amplifier when you leave the car, or it will overheat and drain the battery.
Step 10. Run the subwoofer cables to the amplifier and screw them together
Step 11. Turn the gain knob all the way down, start listening to the music, and then turn the gain up to the level you usually keep it at, where the mids sound good
Adjust the gain of the mids until the subwoofer sounds good.
Step 12. RMS are very important when pairing amplifier and subwoofer
Sure enough power won't cause the subwoofer to clip, but too much power could also burn the coils due to overheating from too much power. The power of the subwoofer and amplifier should be as similar as possible for best performance and longevity.
Advice
- Don't forget to test the remote cable before assuming it works. The last thing you need is a dead battery.
- If the amplifier does not turn on, check the amplifier fuses.
- When connecting a Line Out connector to a factory head unit, it is advisable to use both sets of speaker cables to maintain the left-right stereo effect of modern music.
- Make sure you are using cables with the correct resistance (or impedance) for your system. A bridged amplifier operates with a different impedance than the same amplifier would have without this mode. Using cables with the wrong impedance could cause the cables to overheat or even break the amplifier itself, so make sure the cables and system are matched. Common values are 2, 4, or 8 ohms, so do your homework early.
- Soldering 12v power connectors and ground wires to the wires will reduce the resistance of the circuit and make the power cleaner, giving you better sound.
- Always remember to turn off the amplifier if the ignition is manual.
Warnings
- Always disconnect the negative pole of the battery before doing anything with the car's electrical system.
- Always be careful when working with electricity.
