Once you are done creating a harness after changing the car stereo, you usually add an amplifier to the car stereo system. This can be done by either amplifying a stock set of speakers or an aftermarket set. However, an easier way of doing this is by running the wires from your amp to your stock head unit location to use the existing cabling in your car. In this article, we will show you a step-by-step process on how to follow this alternative so that you’ll be able to learn out how to connect four speakers to a two-channel amp.
As expected, you will be working with many wires and technical terms during this whole walkthrough. So, for you not to get flustered and overwhelmed along the way, it is best to layout and identify the parts needed to connect four speakers to a two-channel amp.
Disassemble Harness and Identify Front Speaker Leads
The first thing you need to do is disassemble the harness by removing the tape surrounding it. Once that is done, you need to identify the front speaker leads of the harness. The front speaker leads can be identified by looking for a white and gray pair within the wires. After finding these pairs, you can start cutting the front speaker’s connections and wire it to the aftermarket speaker running from the amplifier to the factory head unit location. Be sure to cut everything at an equal length.
Labeling the Wires
Before actually soldering up the wires, it is best to label them so as not to, once again, get confused while working on your setup. This helps you identify the left front, right front, right rear, and left rear. You can print nice labels and use heat shrink tubing over them to make a clean label for the wires. This makes it easier to know how to connect four speakers to a two-channel amp.
Preparation for Soldering (Stripping of Speaker Wires and Heat Shrink Tubing)
To prepare for the front speaker connections’ soldering, you first have to strip the wires and cut the heat shrink tubing.
Identify Positive and Negative Wires and Soldering of Front Speaker Connections
After preparing, the next step is to identify the positive and negative wires to match up properly. Wires with solid colors are the positive ones, while their negative counterparts have a black stripe running through them. Once this is finished, you can now start soldering up the connections.
Remote Turn-On Lead
Now that the speaker connection has been made, you need to run the remote turn-on lead. This is done through the process of soldering it and attaching a spade connector at the end to ensure an excellent connection. This is useful if you want to know how to connect four speakers to a two-channel amp.
Take note that you need to check if you need the remote turn on for either the existing speakers in the factory amp, antenna amplifier, or a power antenna. If so, you will need to create T-connection.
Upon finishing the previous step, what you’ll need to do next is to make sure that all of the cablings are at the same length. Then, solder a spade connection to the remote turn-on lead.
Insulating Unused Wires
In unused insulating wires, you can cut them at different lengths so that they won’t touching anything. However, cutting them at the same length and putting a heat shrink at their ends is still allowed.
Tape Up Finished Harness and Make Two-Channel Connection to Amplifier
Now that you have completed the first few steps in knowing how to connect four speakers to a two-channel amp, you can tape up the harness (create a T-harness) and make a final connection.
Connecting of RCA’s from Stereo to Amplifier
Grab a radio and plug it into your car to run your RCA’s properly. It would be best if you connected the front RCA’s as you have only run your front channels from your amplifier to the factory harness.
Once finished, you should have a plug-and-play harness connected directly to the factory speaker wire, your RCA’s to the amplifier, and a remote turn-on from the aftermarket radio.
Wiring a Four-Channel System
Since you aim to connect four speakers into a two-channel amplifier, the next thing you need to do is wire up a four-channel that powers up the front and rears from the factory speaker wires with your four-channel amp.
To do this, you have to cut the connection between the aftermarket radio and the stock speaker connector. Then, you’re going to have to run two more leads coming out of the amp to the rear speakers.
When working on the wiring, you have two options: the first one being to use the second set of RCA’s from the rear RCA output to the rear RCA input, or utilize a single set of RCA with the use of an internal switch to run in two-channel mode.
Doing a four-channel system will lead you to disassemble the harness for a second time.
Disconnect Rear Speaker Connections from Aftermarket Harness
Cut the rear speaker connections from the aftermarket harness to the metro harness. Afterward, cut the connections to the Metro harness.
After doing so, you have to strip, solder, and heat shrink the rear speaker connections. Make sure to use the right cables in making the connections.
Create a T-Harness Again
After all of that is done, you should reassemble the harness by forming a T-harness similar to that of the two-channel setup from before.
Make Four-Channel Connections
Please start with the rear channels first in making the connections as they are located at the bottom.
Learning how to connect four speakers to a two-channel amp can be very tedious as it requires you to do a somewhat similar process twice. However, the results are very much worth it. In the end, you’ll end up the one with the most benefits to gain! Get more tips on connecting speakers.