Adding a line output converter to your car’s stereo system is a great way to get more volume out of your speakers and more clarity and profundity to your music. Many factory stereos included in cars are, frankly, not that good, so many audiophiles opt to install a custom line output converter to connect to their car’s speaker system.
In short, a line output converter is a good way to turn a mediocre speaker system into something that really pops. Unfortunately, car electronics and audio equipment are some tricky business and many don’t know the first thing about how car speakers work or how they can install a line output converter.
Table of Contents
So, What are the Best Line Out Converters?
Editor's Choice
AudioControl LC2i PRO 2-Channel Line...
Best Performance
DS18 V5HL 5-Channel Line Out Converter,...
That is where we come in. We have combed through the internet and put together this ultimate buying guide for the best line out converters. We will cover the 5 best line out converters available now, as well as a buying guide that includes important features to look for, the different types of line output converters, how to install a line output converter into your car’s factory stereo system, and frequently asked questions. Without any further ado, let’s get to it.
Design and Materials
Starting off our list is the LC2i PRO 2 channel line out converter from AudioControl. This line out converter has 2 active speaker level inputs which each accept up to 400 watts of signal per channel. The LC2i requires +12V to run properly and so is an active line out converter. The LC2i has GTO (“great turn-on”) signal sense that automatically detects when a signal is carried to the left speaker input, turns the converter on, and sends the signal to the desired amp. With the remote out options, the LC2i can turn on up to two other devices in the signal chain.
You can also choose the previous version which is is also good AudioControl LC2i
Benefits
The LC2i also comes with AccuBASS bass correction software that corrects the signal to account for any bass that may have been lost when the signal is transformed. The AccuBASS is somewhat like an EQ, which will boost 50HZ to 125Hz and it only activates when bass tones reach a certain threshold.
Pros
Easy to install
AccuBASS bass correction software
With with single or double channel input head units
Cons
Some accessories are not that good
The DS18 V5HL is a high-performance 5-channel line out converter that directly integrates a 5 channel OEM head unit with front, rear, and sub-channels. Each channel is rated for 50 watts and has a 4V output range. The metal casing doubles as a shield from ground noises and electromagnetic signals from other components of the car. It also has an auto signal detection and time delay control to prevent amplifier malfunction and annoying popping noises when activated.
The most obvious benefit of the V5HL is its 5-channels. Each channel has a separate knob to control output levels and LED indicators that represent the status of the signal connection and register any clipping. The metal casing is compact, sturdy and can be directly mounted with screws. The V5HL also comes in 3 other models with 2, 4, and 6 channels. The V5HL installs easily, has great sound quality and has virtually no detectable activation bump or delay.
Pros
5 channels give a lot of options
Affordable
Discreet can easily installed
Cons
Slight interference if you run all 5-6 channels
Can run slightly hot and make noise
Another from AudioControl the LC7i 6-Channel line output converter is like the more powerful big brother of the LC2i and comes with all the upgraded features and functions you would expect from an older sibling. The LC7i ups the available output channels from 2 to 6, each rated for up to 400 watts of power. The more channels mean that the LC7i is larger than the LC2i and a bit heavier at just over ½ lb. Like the LC2i, the LC7i features the AccuBASS bass correction software and is compatible with the ACR-1 dash remote which lets users remotely control the frequency output.
The LC7i is great for integrating a factory head unit and boosting preamp signals for louder clearer tones and bass. The 6 channels give you a lot of flexibility in stereo setup and can run a modest 2 speaker system up to 4 speaker amps, a sub, and mid-range amp. Like the LC2i, each channel has its own output knob that modulates the gain and LED indicators that detect and clipping and signal interruptions. The compact black case is discreet and easy to install and the AccuBASS software keeps the bass prominent at high-listening levels.
Pros
6 output channels offer versatile speaker setups
Clear up the whole signal, mids, lows, and highs
Channel summing features lets you feed speakers easily
Cons
Can be confusing to install if you don’t have some technical knowledge
AccuBASS may not play nicely with some subs
The Kicker KISLOC 2-channel line out converter hails itself as the “world’s first micro surface mount line-out converter” and features 2 speaker-to-RCA channels. Each channel can take up to 50 watts of input and deliver up to 8 volts of output, a surprisingly large range for such a small and low-power line out converter. This range allows it to deliver great sound quality with a small energy footprint. In addition to the 2 basic output channels, the KISLOC-2 has OFC wire for bass response and signal clarity, a flat frequency response from 20-20,000Hz, and “K-grip” dual mold connectors that ensure a solid and tight connection.
One of the best features of the KISLOC is its price. At just over $20, it is a veritable steal considering the sound quality it can generate. Since it only has 2 channels, the KISLOC is best suited for minimalist speaker setups. The enormous frequency response range means the device faithfully picks up every sound and the 8V output is enough to run powerful speakers. The device itself is small and easily installed; it can fit discreetly under the sill of your door frame or under your glove compartment box. Installation is easy and only takes about 20 minutes and a pair of wire cutters, and a soldering iron.
As it only has 2-channels, the KISLOC is not incredibly versatile. Even though it does have very good sound quality for the price, it can’t stand up to some more expensive converters. However, if you want a cheap and reliable line converter to try out, there is virtually no risk to trying the KISLOC.
Pros
Very affordable
8V output is rather high
Very large frequency response rate (20-20,000Hz)
Cons
Only 2 channels
Not incredible quality
The last item on our list is the PAC SNI-35 line out converter with 2 channels that serves as an additional set of pre-amps for a head unit with only 1 set. The SNI-35 has a response rate range of 20-10,000Hz and each channel is capable of handling 2-40W of power. The structure of the converter is designed to isolate input and output circles to eliminate ground loop noise and electromagnetic interference from other car components. The unit is passive and does not require an external power source.
The first thing to notice about the SNI-35 is how cheap it is at only $8. You may think this means it is poor quality, but au contraire, the SNI-35 is rather powerful considering how small and low-powered it is. It is passive so it won’t draw any power from your battery and it is extremely easy to install and connect the wires. This line converter will breathe new life into your speaker system without burning a huge hole in your wallet.
Pros
Extremely affordable
Simple, no-frills design
Separate knobs for each channel output level
Cons
Not incredible quality materials
Relatively short-lived
Line Out Converter Buying Guide
In this section, we will cover the basics of line out converters: what they are, how they work, the different kinds of line out converters, and what features you should look for in a line out converter.
What Is a Line Out Converter?
Let’s talk a bit about how car speaker systems work. Most car speaker systems are made of three major components: the head unit (or radio) which controls the entire system and generates the initial audio signal. The second component is called the amplifier which increases the strength of the audio signal so that it is strong enough to move the third component, the speakers.
Here are the basic mechanics: the head unit produces the audio signal. Initially, the signal is too weak to do anything so it is passed to a preamp which boosts the signal a little bit. The signal is then fed into the amplifier which boosts the strength of the signal a lot. Now that the signal is strong enough, it is passed to the speakers whose vibrations produce the sound you hear from your speakers.
Most people think that the majority of the sound quality of a car’s stereo system is due to the speakers. While speakers are important for sound quality, they are only half the story. The real thing that determines the bulk of the sound quality is the amplifier. In short, the more powerful amplifier you have, the stronger the signal and the louder and clearer the sound.
The problem is that most factory car stereo systems do not fully utilize their amplifiers. That is where line out converters come in. A line out converter (LOC for short) is a device that you hook up to the head unit of your stereo system to convert the head unit signal into a signal better suited to drive the preamp inputs in amplifiers.
In other words, a line out converter is a way to get the most out of your car’s stereo system without replacing the amplifier and head unit. It is rare for factory head units to have preamp outputs, so an LOC gives the connection you need to add an amp. Many folks want a way to upgrade their car stereo system without replacing their radio, whether because it looks good in the dash or the car is leased. Tapping into the speaker wires with an LOC gives the connectivity to do so.
How Does an LOC Work?
A high-powered line out converter usually consists of a transformer and a high-power resistor. When the head unit is switched on a produces an initial audio signal, there is a large spike in the DC voltage. The resistor of the LOC loads this signal and the transformers pass the voltage spike to both ends of the LOC, so that they increase in voltage simultaneously and cancel each other out. Ultimately, this process increases the quality of the signal and shields the amplifier from any DC pulses from the head unit that can affect sound quality.
The best line out converters also have 1 or 2 extra wires that are used to ground the shield of the output cables to the head unit. This allows the LOC to be grounded to virtually any point of the vehicle without the chance of creating a ground loop
Where Do You Install an LOC?
Generally, an LOC is installed between the speaker output wires of the head unit and the speaker input wires of the amplifiers. You cut the speaker wires, hook them up to the LOC, and run the new wires from the amp to the other side of the wires that were cut. So the LOC goes in between your head unit and stereo amplifier.
What Kinds of LOCs Are There?
LOC normally fall into two types: passive and active converters.
Passive converters are low power converters that essentially only scale down the voltage from the speaker lines. Since they are passive, they do not require an external power source. The one major downside of passive converters is that they can only drop the signal they receive from the head unit. If they receive a low signal, they will have low output.
Active converters, in contrast, actively modulate the signal sent from the head unit. Active units are more complex than passive converters and usually have additional features like bass restoration, remoter turn on, and line driver capabilities. Most active converters can handle up to 400 watts per channel which means they can be used with practically any high powered stereo system. Most active converters require at least +12V to run properly. The best line out converters are usually active converters.
Features to Look for in a Line Out Converter
Before buying, make sure you are familiar with the following features of line out converters.
Output Levels
The output level of your line converter is basically a measure of how “hot” the output signal is. The general idea for the best sound quality is to send the highest possible undistorted signal out of the converter that won’t overload the max gain input of the amplifier. Basically, the output voltage of your line converter should be roughly the same as the max input gain sensitivity of the amplifier. For instance, if your amplifier has a max input gain sensitivity of 5V, then you want your line converter to be set to a 5V output. Any higher can overheat the components and quickly turn your amp into a toaster. Any lower and you won’t get the full quality sound the speakers are capable of.
Input/Output Channels
The number of input channels on your line out converter refers to how many speaker output lines from the head unit it can connect to. The number of output channels refers to the number of speaker amps the LOC can connect to. Basic LOCs usually have at least 2 input and 2 output channels, while more complex models can have up to 6 of each. The more output channels you have, the more connections to the amp you have and the more speakers you can hook up.
Input/Output Channels
The “accessories” of a line out converter refers to all the functions the converter performs aside from modulating the line-level signal. Active line out converters usually have a suite of applications that can enhance the quality of a signal, including bass boost, EQ leveling, channel summing, and remote turn-on.
Line Out Converter FAQ
How Do I Install a Line Out Converter?
In the good old days, car stereo systems were hooked up with a simple system of bare and twisted copper wires. Most cars still use this single wire system to connect the head unit output to the speakers. This is the spot that the line out converter should be installed.
Here is a simple step-by-step instruction on how to install a line converter. All you will need are a pair of wire strippers and a soldering iron, 2 tools that can be found for cheap at a nearby hardware store.
- First, begin by locating the wires that connect the head unit or amp to the speakers. Most of the time, these are single copper wires that are located directly behind the head unit.
- Next, use the wire strippers to remove about 1 inch of rubber from each of the speaker wires. Attach the left speaker wire to the left channel of the LOC and the right to the right channel. Make sure you get these connections right. You can damage your amp or head unit if they get installed with the wrong leads on the wrong terminals.
- Using a soldering iron, seal the speaker wires to the LOC and secure the LOC to the vehicle. Most LOCs can be screwed into the car directly.
- Plug the RCA cables into the LOC and connect them to the desired amplifier.
- Set the amp’s gain setting to medium, turn on the stereo, and adjust the volume to a comfortable listening level. Turn the channel level up on the LOC until you hear a slight distortion, then turn it down until it goes away.
- Turn the volume up on the head unit without playing anything and listen for distortion. If there is some, adjust eh amplifier and LOC gain accordingly until there isn’t.
Again, it is very important to make sure you check the polarity of the speaker wires before connecting the LOC. Attaching the positive wires to the negative terminal can cause a loss of volume, sound quality, and possibly damage your sound equipment.
Do all amps require a line out converter?
Nope! There are many amps that have speaker-level inputs and so have no need for a separate line out converter. Powered subwoofers, for example, often have speaker-level inputs perform the conversion inside the amplifier. Most factory amplifiers do not have speaker-level inputs, which is why line out converters are usually used with stock stereo equipment.
How many channels should I get?
The answer to that question depends on what kind of speaker setup you want. If you want a big powerful car speaker setup with front and back speakers and a subwoofer, you will need at least a 5-channel, 4 for the corner speakers and one for the subwoofer. The number of channels also depends on how many channels the amplifiers have. Most consumer cars have a 4-channel amplifier that feeds into the 4 main speakers. In other words, you need to make sure you have enough channels on your LOC to power each of the amps for the speakers.
How should I set the output levels of my line out converter?
In general, you want the voltage output of your line out converter to be the maximum gain input that your amp can handle. Doing so ensures that your amp is being used to the fullest but you are not overtaxing it. So if your amp’s max gain input level is 8V, then you want to set your LOC to 8V output.
Do line out converters require an external power source?
It depends on the kind of line out converter you get. If you get a passive converter then no, you do not need an external power source. Passive converters only modulate the voltage which does not require any active monitoring.
Active converters, on the other hand, do require an external power source, usually at least +12v. Most active line out converters simply hook up to your car battery to get their power. Active converters are also made to only draw power when they are receiving a signal, so they should not drain your battery if left connected. Active converters require a power source because they do more than just modulate the voltage using resistance.
Can a line out converter damage my stereo system?
Only if it is installed incorrectly or set to the incorrect levels. For instance, if you reverse the polarity of the leads when connecting the converter, you can induce a reverse current which can harm your car’s electrical components. Alternatively, if you have the gain output level set higher than the max gain input levels of the amp, you can damage the amp and speakers. However, as long as you keep things within the right parameters, a line out converter should not damage your stereo equipment whatsoever. Most car stereo systems are not built to take full advantage of their components, so you can bump up the juice quite a bit without fear of breaking things.
Why should I use a line out converter instead of an amp with speaker-level inputs?
The main reason is that advanced line out converters usually offer extra features and functionality that amps do not. Active converters have things like onboard equalizers, higher preamp voltages, and restoration circuitry which gives you more precise control over your sound. While amp with speaker-level inputs are easy to set up because they have fewer components, a line out converter is less restrictive in what you can do. Line out converters tend to be less expensive than buying new external amps with speaker-level inputs.
Conclusions
Line out converters are a great way to get the most out of your factory stereo system without having to replace the head unit or amps. A good line out converter will bring up the highs, define the lows, and contribute to an overall better audio experience. This list of the 5 best line out converters will serve as a jumping-off point as you research the market.
