We all wish that upgrading your car audio was as simple as adding new speakers. In theory, replacing your OEM with equipment made with quality materials should help you make the jump from tolerable to excellent performance. But as tech advances, not many factory radios are programmed to cooperate with aftermarket units. Most times, the stereo is not equipped with the proper connections to even add an amplifier. 

So if you’re looking to add more power, the first thing we’ll recommend is adding an amp – but how is that done without having to rip out the stereo and replacing it with a more expensive product? 

If you’re keen on keeping the original look of your dash, and protecting your wallet, the audio industry has created a tool to modify your factory stereo’s existing outputs and convert them into connections amplifiers can use.

Passive Line Output Converters

A Line Output Converter (LOC) is a simple device that connects to the stereo’s speaker wires and converts them into a RCA output that can communicate with the amplifier. On a technical level, LOCs change the signal with an internal reduction transformer that runs the power through two sets of coils that brings down the voltage. In layman’s terms, they change the wire from one type to another. 

A painless way to tackle this problem is to install a basic, passive or non-active, LOC. The PAC SNI-35 is a passive LOC that’s compatible with all factory radios. This is the simplest version of an LOC and easy for anyone to install. Just turn off and disconnect the car battery beforehand. (LINK TO INSTALL)

Active Line Output Converters

Of course, if an audiophile is already altering their set up, they may want to invest in a product that provides more audio and power management. 

NVX has developed a line of LOCs that offer more than wire conversion. The XLCA2X  does everything the passive version can do plus some astounding audio quality management features. 

Not only can you keep your factory stereo and all the controls you’ve become familiar with, you can “set and forget” the XLCA2X for bass and amplifier gain, flip on a low-pass filter and auto turn-on your amplifier. Essentially setting a cruising altitude for how you want your audio to perform before messing with the stereo’s equalizer. 


Products like this make installation a lot easier too. Many modern vehicles make it difficult to find a 12 volt ignition or switched power source used as a remote wire to turn on an aftermarket amplifier. Premium LOCs like the XLOC line have a built-in auto turn-on circuit that can detect the audio signal in different ways to provide a 12 volt remote turn on for your amp.

It keeps your car battery from working overtime or taking power away from necessary non-audio fixtures like the headlights. The advanced LOCs are a major step up from its passive cousin. This is what makes LOCs an excellent partner for an amplifier and your juiced up system – active LOCs can address factory stereo shutdowns with a built-in load resistor so it doesn’t see the LOC connection as an unpowered, empty circuit and turn off the audio.  

If you’re trying to amplify your system, may as well invest in something that will keep the audio playing as it should. 

Advanced Line Output Converters

If you’re looking to only add a subwoofer to beef up your bass, a passive 2-channel LOC could be just what you need. But If you want to amplify a multi-channel, multi-speaker setup, you will need to select an amplifier and an LOC with the correct number of channels to run to each speaker.

Active LOCs truly provide more bang for your buck – you can purchase contemporary line output converters that have been designed with a series of channels/outputs for each speaker set.

The NVX XLOC66X is a 4- or 6-channel line output converter. It provides individual control over the front, rear, and subwoofer gain – on top of all the insane aforementioned features. It has a load selection switch (20, 60 or 20k Ohms) to prevent shutdown, an adjustable bass boost and a full range or low pass filter. Not to mention a selectable ground wire to eliminate engine noise.

The Audio Control LC7i, like the NVX piece, can negate bass roll off and other audio distortion issues but for 6-channels. So no matter how high you crank the volume, your system won’t kill those low frequencies or muddle up signals from the head unit. 

As always, consider your budget and plans for your car audio system before purchasing a new product. Our customer service folks at Sonic Electronix are always here to help.