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Connect A Subwoofer To A Car Stereo [5 Damn Useful Steps]

  • 4 min read
How To Connect A Subwoofer To A Car Stereo Without An Amplifier

Last Updated on by GuestAdmin

In most instances, To connect a  subwoofer,it has to be paired with an amplifier before connected to the stereo of the car. However, this ought not necessarily to be the case. It is indeed possible to bypass this requirement and make a direct connection with the stereo. In that case you must have profound knowledge on how to connect a subwoofer to rear speakers without amp.As a precaution, you are strongly advised to run only one subwoofer in case you choose not to use the car amplifier (external amp). This is to prevent the possibility of overwhelming the power supply systems of your car. Also, you do not want to create too complex a connection that you cannot operate on your own. In the discussions that follow here below, we are going to take you through the step-by-step procedures to follow to do the job.

How To Connect A Subwoofer To A Car Stereo

Tools Required

  • Screw & Pliers
  • Spanner & Hammer
  • Tester
  • Soldering rod (optional)

Disconnect the speaker wires

Disconnect the speaker wires from the various speakers in your car or from the parcel shelf. Switch off your car’s infotainment system to ward off the likelihood of shocks and electrocution. Thereafter go ahead to remove the pins from their slots. The aim of this disconnection is to create a favorable environment for the subsequent role of attaching the relevant wires. That is because live wires are potentially dangerous and generally probe to the risks of electrocution and shocks. To do so, simply locate the main power supply unit of the car. Switch it off after which you are to proceed to physically disengage the wires from the various slots and terminals.

Identify The Relevant Output Ports

Proceed with identifying the relevant subwoofer output port. Look out for the low-frequency effects (LFE) output port. This is the port which handles those low-pitched and deep sounds which range from 3-120 Hz.

This output port is labeled, ‘SUBWOOFER’ or ‘SUB OUT’ which connects to the stereo of the case. In case you have not seen it even after following the procedure above, refer to your manufacturer’s manual. 

Establish The Relevant Connection

After having identified the relevant output ports, you now have to establish the relevant connections. To do this, simply connect the LFE jack on the receiver to the output port of the box of the subwoofer. In most makes of subwoofers, this jack is usually the only RCA connector on both ends of the device. You will generally have to simply slot in the jack to the hole which is available on the port.

Reinforce The Connections

Move on to reinforce the connections. Attach the positive speaker wires which emanate from the subwoofer box to that of the left rear panel speaker which is marked as (+). Then, go ahead to connect the negative speaker wire which originates from the sub box to that of the right rear speaker which is marked (-). This arrangement will guarantee you the highest power levels from your car stereo system. Test the device before moving on to the next stage. After you are through with this stage, you should yet again test the system to see to it that it is flawless. Use a tester to check whether the flow of the current is flawless or not. Simply place the tip of the tester on the live wire and observe the indicator. You will obviously have to make some adjustments in case you do not notice any signals.

Enclose The Subwoofer

After establishing this connection, you now have to enclose the subwoofer in an appropriate box. While at this, be sure that the cone side faces away from the seat preferably pointing towards the direction of the trunk lid. This arrangement will confer to you the benefit of louder sounds while inside the car as it will bolster the cabin gains.


Even though the procedure of installing a subwoofer to a car stereo without incorporating an amplifier is not so complicated, you do not want to take chances. That is because the entire procedure is ordinarily dangerous due to the possibility of sustaining electrical shocks and damaging your car’s electronics system. It is for this reason that you want to invoke the assistance of a qualified electrician to help you out. Find someone who has already done it. Let the person guide you as you pay some keen attention throughout each stage of the journey. Never hesitate to ask questions if you are stuck.