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How to Install a Bass Knob in Car

If you love a heavy bass, you may want to increase it without interfering with the volume of the music.

Also, sometimes the music might have a heavy bass, and you might want to reduce it and make the high frequencies more audible.

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The best way to adjust the bass is to control its level directly from the dash, but how to install a bass knob in the car? Let’s find out.

Generally, to connect a bass knob in the car, take an RCA output connector of the bass knob and connect it to the RCA input connectors of the amplifier. Next, connect the RCA input connectors of the bass knob to the RCA output connectors of the car head unit.

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Tip: With a bass knob, you can fine-tune the bass in your music without changing the gain configurations on the amplifier. Unfortunately, not all factory or aftermarket amplifiers are equipped with a bass knob.

If you do not have a bass knob in your car and want better control over the bass, you can use the universal CT Sounds, which is also equipped with a digital voltmeter.

In this article, I will show you how you can install a bass knob in your car audio.

How Can I Install a Bass Knob in a Car?

Installation of the bass knob depends on its type, and in general, for the standard bass knob design, only the RCA wires need to be connected with the RCA wires between the head unit and the amplifier. 

However, you may need a bass knob that requires a different way of connection if the bass knob you use has additional wiring for the car battery.

CT Sounds Universal Bass Knob - Digital Voltmeter, Blue LED Display, Remote Gain Control, Power Switch, Durable, Pushable ON/Off for Amp

If this is your bass knob, follow the steps below:

  • Connect the positive red cable of the bass knob to the positive terminal of a car battery.
  • Next, connect the black negative cable to the battery’s negative terminal. 
  • Finally, connect the remote turn-on cable of your car head unit to the orange cable of your bass control knob.

The bass knob regulates the frequency mix level in the lower part of the sound spectrum. The subwoofer knob controls the Gain on the signal that goes into the amplifier, so reducing the bass only changes how the treble frequencies and bass frequencies relate. 

In most cases, you will only need to increase or reduce the low frequencies depending on the type and genre of the music without interfering with the high frequencies of amplifier settings.

This is especially helpful in the case of 99% of car audio installations, where the amplifier is placed in the trunk; therefore, you cannot change its configuration while driving. 

Installing a bass knob in a convenient and more accessible location, such as below the car steering wheel or in the dashboard, will help solve this problem.

CT Sounds Universal Bass Knob - Digital Voltmeter, Blue LED Display, Remote Gain Control, Power Switch, Durable, Pushable ON/Off for Amp

Depending on your car and the other accessories installed in your vehicle, you can even install a bass knob in an empty switch panel, inside the center cubby, or in the center console near the gear shift knob.

Depending on your location, you can attach it in a flush with only the knob showing.

Choose a Compatible Bass Knob

There are many types of bass control knobs on the market, and the main difference between them is how they attach to the amplifier.

Typically, different car amplifiers come with different connection types, and you need to look for a bass knob that can match the connection type of the amplifier.

For instance, some use RCA cables, while others are universal knobs that connect directly into the amplifier.

Connect the RCA Connectors

An RCA is an electrical connector mainly used to carry video and audio signals. However, you can also use it as an RF connector, DC power connector, or as a connector for loudspeaker cables.

RCA signals are often color-coded: red for the right audio channel, yellow for composite video, white or black for the left stereo audio channel, orange for digital audio, and green for the center audio channel. 

In most cases, the bass knob comes with short RCA connectors, and you might need to increase the length of the cables by hooking up additional RCA cables, especially if your amplifier is at the trunk.

Considering that you’ll be using the RCA cables to connect the bass knob to the amplifier, the quality and thickness of the cable will play an essential role in the sensitivity of the bass knob. 

For instance, RCA cables need to have the proper shielding to prevent sound distortion.

Also, the RCA cable will be transmitting a line signal from the car head unit to the amplifier. Because the signal from the radio to the amplifier is not amplified yet, the resistance of the RCA cables can have a significant impact on the final bass quality. 

Therefore, it is advisable to go for high-quality, thick, and well shielded RCA cables. An excellent example are the wires from the ELITE Audio.

Elite Audio PRO 100% OFC Copper 2 Channel 17 ft RCA Audio Interconnect Stereo Cable with Triple-Shielded Armor, Quad Clamp Brass Copper Connectors & Copper Lead Drain Wire for Best Noise Cancellation

When you have the correct RCA wires in hand, attach the signal outputs (blue and white) to the amplifier and then RCA signal inputs (red and green) to the car head unit.

Although this color coding might differ with the brand, in most cases, the bass knob will have a label on the output and input connectors.

Connect the Remote Turn-On-Cable

The turn-on cable is the remote wire located behind the head unit. For most car radios, it is a blue and white cable coming from the back of the stereo harness.

When you turn on the car, this cable provides the amplifier a signal when to turn on.

If you however connect this cable to another wire in the vehicle with a constant voltage, the amplifier will remain on even when you will turn the engine off, so it is important to remember that it should be connected only to the car radio. 

When you turn the car’s ignition off, the remote wire stops transferring current, and the amplifier switches off.

You need to hook up the remote turn-on-cable from the back of the stereo to the orange cable (remote in) in your bass control and then connect the blue wire to your amplifier.

Set the Head Unit and Amplifier Bass to Medium

Considering that you will adjust the bass of your car stereo system using the bass knob and not the amplifier or the car head unit other than the volume, you need to set the bass to medium.

However, for the best bass experience, it is advisable to remove the sound distortion from your stereo system.

Minimize the Gain in the amplifier, and then increase the volume of your head unit until you hear some sound distortion. 

In most cases, you can minimize the Gain by turning the knob to the counterclockwise direction and maximize it by turning the knob in the clockwise direction.

Usually, this is the maximum volume that you can use in your head unit without sound distortion.

You can also opt to use ⅔ of your car head unit’s maximum volume as your maximum volume settings.

  • Minimize the Gain in your car head unit and increase the Gain in your amplifier until you hear some sound distortion. Typically, this is the maximum Gain you can set in your amplifier without hearing any sound distortion.
  • Note these settings as they are the maximum volume settings you can use without sound distortion.
  • Now, increase the amplifier and the head unit gain to these levels, turn the amplifier bass to the lowest position, and increase the bass using the bass knob to the top position.
  • Note that some universal bass knobs come with a rotary push turn switch for turning them on and off, so ensure the best knob is on.
  • In most cases, the knob will have an indicator light to indicate when it is in its top position. Start increasing the amplifier bass while listening to sound distortion.
  • If the amplifier bass knob causes a sound distortion before reaching the middle line, minimize it slightly and leave it at this level.
  • On the other hand, if the amplifier bass knob gets past the middle line before causing sound distortion, set it at the centerline. 

If you have a bass boost in your system, turn it up carefully to avoid sound distortion.

Keep in mind that a bass boost can cause damage to your car amplifier or subwoofers if you fail to set it correctly. Therefore, it is advisable to leave your bass boost with the default settings or at zero Gain.

If it is a must you use it, it is also advisable not to use it in both the amplifier and the car head unit at the same time.

With these settings, you can now use your bass knob to increase or reduce the bass with the sound remaining clear.

Can I Use Any Bass Knob for My Amplifier?

Bass knobs are in general, universal devices. However, in most cases, they work in the best way when they are from the same manufacturer as the amplifier.

This compatibility is because they have similar physical characteristics, and the signals and circuitry from the bass knob to the amplifier are the same for similar models. 

Bass knobs and amplifiers from different manufacturers might not work because some use standard phone jack plugs while others use standard plugs.

Additionally, their signals and circuitry are usually different, with varying current demand and voltage levels.

Xtenzi Amplifier Bass Volume Knob Control Remote XTBR6 Compatible with XThunder Link Amp

On the other hand, there are universal bass knobs that work with almost any amplifier on the market. Some of the universal bass knobs also come with a multimeter that can help you monitor the power usage of your car’s electrical system. 

These types of bass knobs also come with two extra cables, the red one connecting to the car battery’s positive terminal and the other black to the ground or negative terminal.  

Does Bass Knob Affect Gain?

Understanding what a bass knob does to your audio signal is essential. Typically, a remote subwoofer control is an external gain that allows you to fine-tune your music to achieve the bass level of your desire.

Connecting it to your amplifier essentially means avoiding the gain control in the amplifier. 

Generally, turning the bass knob up means adjusting the audio signal that your subwoofers are receiving. So, excessive turning up of the gain control may result in sound distortion and clipping.

The purpose of the gain control is to determine how far you can increase the head unit’s volume for the amplifier to reach its maximum power. 

A correctly set gain prevents damage to the subwoofer and reduces distortion and background noise.

If you set the Gain excessively high at higher voltages sources, your amplifier reaches its maximum power at a reduced volume control configuration from the source unit.

On the other hand, if the gain settings are too low, the amplifier will not be in a position to reach maximum power, and the sounds will be weak.

Usually, this makes the source unit clip resulting in the delivery of the distorted signal to the speakers. Low gain settings are ideal for sources with lower than 2.5 voltage.

Unlike volume, which is the power of the outgoing signal from the amplifier, Gain refers to the power of the input signal from the car head unit. 

That means that the bass knob will be affecting the frequencies at the gain level but not volume.

For instance, when you use the bass knob to reduce the bass, you will be reducing the low-frequency gain without affecting the high-frequency reaching the amplifier.


After installing a high-end aftermarket car head unit, high-quality amplifier, and subwoofers, you will want a convenient way to control the bass on the system.

The most viable option is to install a bass knob between the car head unit and the amplifier.

To make it correctly, first look for the most convenient and easy to reach location in your car, and then use the above step-by-step guide to install the bass knob.

Frequently Asked Questions

Can Bass Boost Lead To Clipping?

Bass boost can lead to sound clipping, and in fact, it is the main cause of clipping. Typically, every time you increase your bass boost by 3 dB, the amplifier will need to double the power output at the same volume.

For instance, if music is recorded at 0 dB and you set your amplifier’s bass boost to +9dB, you may force the amplifier to produce thousands of watts over its capacity.

If the amplifier cannot produce this power, it will try to amplify but with a lot of distortion, causing the clipping.

How Can I Minimize My Subwoofer Distortion?

You can minimize subwoofer distortion by using low bass and Gain or using High Pass Filters for your subwoofer.

The filters help to eliminate the low bass and distortion, delivering a more clean and clear sound.

Car subwoofers might also be distorted because you don’t have an amplifier, or your amplifier is not producing enough power.

The best solution would be to upgrade the amplifier to one with sufficient power.

Can Bass Damage My Subwoofers?

Excessive bass can damage your car subwoofer, especially if played at a high volume for a long time.

The damage occurs due to over-excursion when the subwoofer’s cone is forced to move way beyond its limits. 

This, however is not the easiest to clarify, and it depends on the following:

  • how low the frequencies are
  • at what volume they are being played
  • the power of the amplifier
  • the size and type of the subwoofer