This guide will tell you how to connect a subwoofer to your car stereo.
Steps
Step 1. The cheapest thing is to buy an amplifier wiring kit from a website
It will include a very thick wire used for power, a short wire used for grounding, a remote wire and often a fuse and other connectors to help you keep the wiring neat and clean. Some stores sell large spools of thread that can be purchased by the meter. This is an inexpensive alternative to purchasing a wiring kit, as long as you know the size of your car.
Step 2. Run the power cable (usually the longest in the kit, often red in color and often 8 to 0 in diameter) from the battery to the amplifier
Do not connect the cable to the battery and amplifier yet.
Step 3. Look for a metal ground near the amplifier
You will need to stay 60-90cm from the amplifier to have the best possible grounding. One way to do this is to lift the car carpet up to the pure metal by removing the paint. If the amplifier goes in the trunk, you can often find the suspension nuts directly above the rear wheels. Suspension components are usually bolted directly to the frame, making them an ideal grounding point.
Step 4. Take the car stereo out of its housing
There will be a blue and white cable coming out of the back, it is known as the remote cable. The remote cable is a cable that carries a 12V signal from the car stereo to the ignition amplifier.
Step 5. Take the remote cable from your kit and connect / tin it to the white and blue cable, then run it along the dashboard and finally through the door
Step 6. While you still have the car stereo removed, connect the red and white RCA cable to the back of the car, where it says "Subwoofer Output"
If your car stereo does not have a "Subwoofer Output" label, or if you are using the stock car stereo, you will need a device called an "inLine converter". It is a small box with 4 inputs and 2 RCA outputs that you will connect to the amplifier. It takes the high voltage signals going to the speakers and converts them into low voltage signals to match the amplifier. The 4 inputs must be connected to the rear speakers (+ and - both on the right and on the left).
Step 7. Route all cables to the amplifier
You should run the power cable and remote cable from the right side of the car as the original speaker cables go to the left and if the power cable is adjacent to the speaker cables and there is a short circuit, the car stereo it could catch fire. RCA cables should be routed through the center of the car as they can be disturbed by other electrical signals.
Step 8. Use the speaker cables to connect the subwoofer to the amplifier
The thickness of the cables here is not that important, as long as the cable is copper the resistance per meter is in the order of milli ohms, which means that if there were voltage drops in the cable, they would be practically imperceptible.
Step 9. Hopefully, you already have a subwoofer enclosure at this point
There are different types (sealed, open, band pass, etc.). There are endless articles explaining the pros and cons of each type of crate, and there are too many to include in this guide. If you want to get the best out of your subwoofer, its manual will surely tell you the right volume for each type of speaker. If you don't want to waste time doing all the calculations necessary to find the right volume, buy a speaker that is slightly larger than necessary and fill it with pillow filling until the subwoofer reproduces the desired sound.
Step 10. Make sure you know the impedance of your subwoofer and try to match it to that of your amplifier
For example, if you have a 500W at 4 ohms, and 1000W at 2 ohms amplifier, you will want to run your speakers at 2 ohms. Two 4 ohm subwoofers placed in parallel can make this possible. If you are new to impedance calculations, many amplifiers will have pre-made wiring diagrams in their manuals to help you.
Step 11. Put a fuse on the 12V cable in the hood no further than 50cm from the battery
If your amplifier wiring kit has a fuse holder, look for a space in the hood to mount it. Once secured, cut the power cord to connect it to one end of the fuse holder. Connect the other part of the cable to the other end of the fuse holder.
Step 12. Connect the power cable to the battery
There are ring connectors and even battery terminals that you can buy (or that you may already have in your amplifier wiring kit) that will make the connection between the cable and the battery more secure, and make the whole look better.
Step 13. Finally, connect the power cord to the amplifier as well
Now actually connect the cable to the battery. A little warning: sometimes you will see sparks when the cable first contacts the battery. Do not worry! It's just the amplifier trying to charge the huge capacitors it has inside.
Step 14. Do not turn up the volume too much, otherwise the subwoofer may distort the audio (clipping)
It happens when the amplifier's output reaches peak value and stays there for a moment. This damages the subwoofer because it holds the cone (the large circular part) fully pulled or fully compressed for the duration of the peak. Not only will it not produce any sound in that microsecond, but it will also risk getting damaged. A good rule of thumb for beginners is to play a song of your favorite genre and set the volume to 3/4. Now, with the gain at 0, turn it up until it seems clear that the sound can't get any higher than that. The gain knob is nothing like the volume knob. A gain knob should never be set to maximum.
Suggestions
- Make sure you do not insert the fuse until the end of the operation.
- Connecting a subwoofer to the stock audio system may require some additional steps, such as connecting the inLine converter as explained in one of the steps or connecting the remote cable to one of the ignition switch cables.
- A good quality used subwoofer can last for years, but unless you are REALLY sure what you are going to buy, a NEW amplifier is the best choice. For simplicity, take a "mono" amplifier, since subwoofers (especially if composed of a single woofer) are not technically stereo.
- If you blow the fuse when you turn on the power supply, it probably means that the grounding is wrong. Unplug it and use a wire brush or cleaner on the grounded area and try again. Otherwise look for a new place to connect it.
- Make sure all cables go well to the amplifier to avoid having to do it all over again.
- Be sure to cover each cable joint with electrical tape to prevent the bare parts of the cables touching metal parts of the car and shorting.
- Be sure to check the fuse box to see if there are any blown fuses. If there are, you may have problems with the amplifier, which may not turn on once connected to the subwoofer. It could be due to any device in the car that only works with the key turned (such as the wipers).
- Find out about sound absorbing sponge or spray to reduce the noise caused by the vibrations of the interior of your car after installing the subwoofer.
- Mount the amplifier under the cover of your trunk, so if you spill something on it you don't risk damaging it.
Advice
- Make sure you do not insert the fuse until the end of the operation.
- Connecting a subwoofer to the stock audio system may require some additional steps, such as connecting the inLine converter as explained in one of the steps or connecting the remote cable to one of the ignition switch cables.
- A good quality used subwoofer can last for years, but unless you are REALLY sure what you are going to buy, a NEW amplifier is the best choice. For simplicity, take a "mono" amplifier, since subwoofers (especially if composed of a single woofer) are not technically stereo.
- If you blow the fuse when you turn on the power supply, it probably means that the grounding is wrong. Unplug it and use a wire brush or cleaner on the grounded area and try again. Otherwise look for a new place to connect it.
- Make sure all cables go well to the amplifier to avoid having to do it all over again.
- Be sure to cover each cable joint with electrical tape to prevent the bare parts of the cables touching metal parts of the car and shorting.
- Be sure to check the fuse box to see if there are any blown fuses. If there are, you may have problems with the amplifier, which may not turn on once connected to the subwoofer. It could be due to any device in the car that only works with the key turned (such as, for example, the wipers),
- Find out about sound absorbing sponge or spray to reduce the noise caused by the vibrations of the interior of your car after installing the subwoofer.
- Mount the amplifier under the cover of your trunk, so if you spill something on it you don't risk damaging it.
Warnings
- Disconnect the battery before working on any electrical components in your car, including bare wires and connectors. A dancer link can damage a relay, blow a fuse, or damage the on-board computer, which is very expensive to repair.
- Be careful not to get the shock because it is quite painful.
- Consult your mechanic or your auto electrician if your car model has special procedures to follow (such as not being able to disconnect the battery, etc.). This is especially true if your car is a very recent model.
