If you have an old head unit that has no RCA jacks and you want to hook up and additional amp in your car audio system. You know it is very complex to install an amplifier in your car and when there are not even RCA jacks available, it becomes a little more complex.
An old head unit is not useless just because of the lack of RCA jacks. You should install an additional amplifier in your car to increase the power for running speakers or subwoofers.
When we move to hook up an amplifier, there are many methods available to perform this task. It all depends upon the type of equipment being installed and the number of methods available to connect.
Related: Connect Phone To Car Stereo Without Aux
Before we start, make sure the amplifier can accept speaker or line-level connections. And the other thing to check carefully is that the RMS power of amp is less or very close to the RMS power of speakers. If it is more than speakers, it can damage the speakers.
RMS: Root means square or RMS is the power at which a speaker or an amplifier can work continuously. Not to confuse with peak power, which is the maximum power a speaker or an amplifier can reach but cannot work at this power for a long time.
Where to place amp in the car?
First of all, you must decide a place to hook up your amplifier. There are many places to mount the amplifier in the car like at the back of a seat, behind the seat, between the seats, sidewall, back of a subwoofer box, etc. Don’t mount it close to any loose item that could damage the amp when you drive the car.
If possible you can also place it in the trunk of car. When you place luggage there, it may become difficult for you. Also, try to keep it at a place where it could get cool air to get cool as it will be getting hot while running.
Safety Tip: For safety, disconnect the negative terminal of your battery before you get started.
![](https://speakersmag.co.uk/wp-content/uploads/2020/08/How-To-Hook-up-An-Amp-Without-RCA-Jacks.jpg)
3 Ways To Hook Up Amp Without RCA Jacks
There are almost three methods available to hook up your amplifier without using any RCA jacks.
1. Connect Speaker Wire To RCA Adapter
This is the first method that we will use to make a connection. Using this method, you can add an amplifier to the old audio setup of your car. This will give a boost to the audio and make your sound loud, clear and increase bass.
Related: Connect Phone To Car Stereo With Aux Cable
Many people don’t even know if they can add an amplifier to the factory setup of their car, but today we are going to show you this.
In this method, we will use two RCA plugs. Connect wires from the speaker into the RCA plug. See in the picture below.
![](https://speakersmag.co.uk/wp-content/uploads/2020/08/Connect-Speaker-Wire-To-RCA-Adapter.jpg)
2. Install Using High-Level Amp Inputs
It is also known as speaker level input present on the amplifier. In these inputs, the voltage is higher than a standard RCA input so called the “High-Level Input”.
These inputs give you clear and amazing sound quality.
![](https://speakersmag.co.uk/wp-content/uploads/2020/08/High-Level-Inputs-on-Amp.jpg)
To hook up your amp with this method, run “Red Power Wire” from your amplifier through vehicle’s firewall, routing to the battery connect with the fuse holder.
Make a connection to the head unit and battery after mounting the fuse holder. Also, route “Red Power Wire” and “Blue Turn-On Wire” under seats or door panels to the amplifier.
Now we have to receive audio signals for each speaker or subwoofer we want running on the amplifier. For every speaker or subwoofer you want to connect with amp, strip back the color-coded right and left speaker wires, and then connect the wire leading to your amplifier.
Related:The Best Equalizer Settings For Car Audio Bass, Mid and Treble
3. Hook-Up Amp Using Line Output Converter(LOC)
![](https://speakersmag.co.uk/ezoimgfmt/images-na.ssl-images-amazon.com/images/I/61u%2BZDTpf5L._AC_SL1000_.jpg)
A line output converter speaker level signals to RCA signals that are used by an amplifier. These are mostly used with two-channel or mono channel amplifiers. You can use this method to hook up your amp without RCA jacks.
Before you start the installation, find the leads connecting your factory radio and amplifier to speakers. You mostly find them at the back of the head unit. Once found, use a wire stripper to strip away one-inch insulation of each of these wires.
In this way left LOC channel will be attached to the left speaker and right channel to the right speaker. Now solder the converter’s wires to the speakers wires and secure them with tape.
Next secure the LOC to the vehicle at some points of attachment and then insert RCA cables into the LOC and run them to your amplifier.
Also Read: How To Wire 2 Channels To 1 Speaker
Final Thoughts
These were 3 best ways you can use to hook up your amp without RCA jacks. If your car’s audio system is old and lacks RCA jacks, there are 3 methods available to connect amp and increase the power.
When you have decided to add an amp to your audio system, it will be a great update and you will enjoy better sound than before.