How to connect subwoofer to car stereo


In many cases, pairing has to be done between an amplifier and the subwoofer. This is before a connection is done to the car music stereo. This does not need to be the process all the time though. One may choose to do a bypass which will enable a connection which is direct to the stereo without passing through the amplifier.

Caution needs to be taken so that one does not make a mistake by using only a single subwoofer when the amplifier is not in use. This is done so as too much power supply from the car systems is not overwhelmed. It also saves on too confusing connections that may be difficult to figure out or operate on. In the following discussion, you shall be taken through a procedure with clear steps on how to carry out this connection task:

How to connect subwoofer to car stereo

Connecting a car music stereo to a subwoofer

Needed tools

  • A tester
  • A rod for soldering (if needed)
  • A pair of pliers and screw driver
  • A hammer and a spanner

We shall begin with the small connection

We require an added battery power instead of relying power from the main source of the engine. This ensures that there is more power that is induced to the car. The rear speaker is then wired as the output of the subwoofer. By doing this, bass that shatters cannot be heard. However, this will add an extra frequency is added to the system of your sound.

You may choose to make the subwoofer the boat anchor. It can also be made the doorstop down on the floor or on the panel of the door. Let us focus on the unit of the head. Some types of head units have power which is inbuilt to bring out sound which is free from distortion. If you add a cross-over high pass together with the unit of the head, the problem is sorted.

Away from this, one can also work with the output of the preamp if the head unit has it. This is because the output passes by the amplifier which is internally built. This sends a signal which blows the mind to the amp which is externally built. These are the few techniques that you can prefer to use.

There is a detailed process of doing wiring and making connections. Of the five mechanisms, let us look at how to connect subwoofer to car stereo even without an amplifier being used. The same process can also be achieved by ensuring that rear panels are connected.

Disconnecting wires of the speaker

Ensure the speaker wires are connected from different speakers of your car. You can also do the same disconnection from the shelf of the parcel. The infotainment of the car is then switched off so that shocks and electrocutions are not experienced. The pins from their slots are then removed.

The main reason of doing this disconnection is to ensure that an environment which is conducive is created for the next task to be performed. The next role to be performed is that of having relevant wires attached. The reason behind this is that wires that are live can be so hazardous and may pose dangerous risks like electrocutions.

To achieve this, just establish the main supply of power unit of your vehicle and have it switched off and then physically undo the wires from their ports or terminals.

Establish ports for output that may be relevant

Continue with the process of identifying the output port of the subwoofer which is relevant for the action. Identify the port for Low-frequency Effects. This port takes care of those sounds that have a low pitch and deep ranging from 3-120.

The label on this port bears the name either as ‘sub-out’ or as ‘subwoofer’ and this connects the case stereo. If you do not see it even after adhering to this process, please check on the manual of the manufacturer.

Identify the relevant connection

After establishing all output ports, find out the connections that may be relevant to this connection process. Make a connection between the LFE jack which is found on the receiver and the output port of the subwoofer’s box. This will differ from one make of the subwoofer to the other. Most models of subwoofers have this jack as the only connector of the RCA found on both terminals of the gadget. Just pin in the jack to the port through the available hole.

Connections to be reinforced

The next step is to have the connections enhanced by connecting wires that are positive whose source is the subwoofer to left speaker bearing the mark (+). Connect wires that are negative whose source is the sub box to the left speaker bearing the mark (-). These two speakers are rear. This kind of connection will assure you the most powerful levels from your vehicle’s stereo.

Make sure the system is tested once the process is over. This is to ensure that the system is working flawlessly. To observe the indicator on the tester while checking whether the flow of power is proper or not, just put the tester’s tip on the live wire. Please be sure to make necessary adjustments if you do not see any signals.

The Subwoofer to be enclosed

Once you have checked every connection on the system, it is necessary to have the subwoofer enclosed in a good box. Make sure the side of the cone does not face the seat. The most preferable direction it should face is towards the lid of the trunk. This position of speakers will give you guaranteed gains from the cabin while making the sounds louder.


Do not take chances when it comes to making a connection between a car music stereo and car audio powered subwoofer. Even if it is not complicated especially when the amplifier is not incorporated, the connection itself may be hazardous because it is prone to electrocutions and in the long run, it may destroy the electronic system of your vehicle.

Therefore, it is imperative to engage an experienced technician to assist you. Most of those technicians that have done it for a while prove to be so resourceful. Be keen on how they are doing it while listening to their guidance. Remember to ask them questions where necessary.