How to tune your car's audio system—Equalizer Basics

Most car stereos are pretty feature-packed. The touchscreen alone was a luxury to have back in 2010. Even before that though, one feature was highly sought-after by audiophiles and that’s an equalizer. Nowadays, most cars come with a built-in equalizer (EQ). This feature allows you to tune the different audio frequencies that come out of your sound system to your specific preferences. 

As far as cars are concerned, most come with only 4 speakers, while higher-end or more premium models come with at least 6 or even up to 12 speakers. Speakers can also be branded for some models. Premier audio equipment manufacturers like Bang & Olufsen (B&O), Bose, Burmester, Harman Kardon, JBL, Mark Levinson, and many others are often contracted by automakers to fit high-quality speakers with preset tuning. For most cars, however, the stock system will be good enough for the average driver, but to get the most out of it, you should consider touching your EQ settings. 

For example, the Ford F-150 features a Bang & Olufsen system that nets higher fidelity audio over the standard. Mazda is also famous for including a Bose sound system across numerous models like the Mazda3 and the Mazda CX-9. 

So there are a few terms that we need to unpack and understand before we head into the guide. Remember that the human ear can hear sounds that range from 20 Hz to 20,000 Hz. 

Treble - A general classification of high-frequency sounds. 

Bass - A classification of frequencies that range from approximately 20 Hz to 60 Hz. This classification can be broken up into two other categories, sub-bass, and bass. 

Mids - A classification of frequencies that range from approximately 60 Hz to 6,600 Hz. This classification can be broken up into three other categories, lower-mid, mid, and upper-mid. 

• Lower-mid - 60 Hz to 250 Hz  
• Mids - 250 Hz to 1,500 Hz 
• Upper-mids - 1,500 Hz to 6,600 Hz 

Highs - A classification of frequencies that range from approximately 6,600 Hz to 20,000 Hz. 

Subwoofer - Often referred to as a sub, this is a classification of speakers that primarily output bass frequencies. 

Woofer - In charge of handling the middle frequencies, and the most common speaker to be installed in most cars, woofers can boast a wide range of frequencies, but are primarily used to project middle frequencies. 

Tweeter - An especially small speaker, tweeters specialize in projecting high frequencies due to their small size. They allow for the brightness and ambiance of a track. 

Gain - Essentially the volume of the equalizer. A higher gain will increase the volume of your sound system or the specific frequency that you are adjusting. 

Most cars come with woofers and possibly a pair of tweeters, but higher-end models come with all three, or a combination of two or more types in one speaker basket. The first thing that you need to know is what kind of setup your car is running. Check your spec sheet, and you will find that most manufacturers will list the number of speakers, and even the types of speakers used. As a general rule of thumb, 6 speakers will have 2 tweeters and 4 woofers. Lower-end models and trims have 2 to 4 woofers, and higher-end setups with a sub, 4 woofers, and 2 tweeters, adding to 7 or more depending on the car.  

Other cars will also come with a sound stage setting or balance setup, which will allow you to direct the sound to a specific location in the vehicle. In general, you want to keep your audio balanced, but if you prefer, you can tune it to be more balanced for the driver. 

There are some equalizers that are heavily simplified, and only feature two tunable frequencies: bass and treble. That being said, boosting your bass will amplify your lower-range frequencies, and amplifying your treble will boost your upper-range of frequencies. 

First off, you need to access your car’s equalizer. That means digging into the settings. Typically, you go Settings > Audio > Equalizer. This string of action menu items is quite common but may vary depending on the brand of car that you own. 

Once you get to your equalizer settings, play a track of your choice, this means you need to connect your phone to your infotainment system or hunt around for an FM radio station playing a song of your preference. Once there, make sure to play the song in the background while you tune. 

You may approach tuning your equalizer by going high to low, or low to high, but since most cars don’t come with a subwoofer, you may want to tune the lower range of frequencies first. 

Bass

Start out with the lowest frequency and increase it slowly. Your ears will notice a difference in how a particular track sounds as you adjust. During this step, do not increase the bass past the point that your speakers can handle. If you hear a bit of rattling or cracking, that means that you’re past the point, and need to reduce your lower frequencies. Essentially, if you want more thump, then give these frequencies a bump. 

Lower-mids (60 Hz - 250 Hz) 

Next, you want to tune the lower-mids of your equalizer. In this section of the EQ, you want to increase the range slightly. Increasing the lower mid will enhance the lower and more pleasing tones in your track, like saxophones and lower notes on guitars. Generally, this frequency is more pleasing to the ear, and some studies show that they can positively affect your attention on longer drives. 

Mids (250 Hz - 1,500 Hz) 

Then you get to the mids, which can tire out your ears if listened to for extended periods of time. Boost your mids sparingly, as they can cause you to fatigue during a long drive. Most of the time, not everyone boosts their mid frequencies and the setting is left square in the middle otherwise known as flat. Others will actually put down the mid frequencies to make the other frequencies shine. 

Upper-mids (1,500 Hz - 6,600 Hz) 

This set of frequencies are the most damaging to your ear given a high enough volume and extended listening time. A more common term for this range of frequencies is treble. Boost this sparingly as it could cause you to fatigue during a long drive or listening session. A properly-tuned upper-mid, however, will create a resonant sound, similar to that of a bell or a chime, but it’s not uncommon to reduce the gain of these frequencies for a more pleasing listening experience. 

Highs (6,600 Hz - 20,000 Hz) 

The high-frequency range is responsible for ambiance and atmosphere. These frequencies give a sense of space and background to a track. Adjusting your EQ to the lower part of this range can make your track a bit annoying to listen to. As such, boost this frequency to add depth to your track and a sense of space. 

At the end of the day, there is no one perfect EQ setting. It’s mostly preference-based, however, a good rule of thumb is to make your graph look like a ‘U’, with your bass and highs boosted, while your mids remain relatively flat, or boosted sparingly. 

You should tune your equalizer based on a few different parameters. Consider what kind of songs you listen to and what genres are your favorite. Different genres often shine best with different equalizer settings. It’s not uncommon for cars to have a preset for rock, electronic, hip hop, and etc. 

Consider your setup, and where your speakers shine best. If you’re running the stock setup, it should be enough to boost the lows and highs, and keep the mids more or less flat, however, if you are running a custom setup, or have a car that features a premium audio system, you may want to spend more time tuning the equalizer to get you preferred sound profile. 

If you need more help, you may want to consult with a car audio specialist, or consult an audiophile on the best setup. They may also recommend upgrading a few components in your speaker setup to get even better audio out of your car. Either way, happy listening.