So, your car speakers are producing static noise and crackling sounds? There is nothing more annoying than expecting to chill to crisp and satisfying music from your car stereo only to hear static screeching from your speakers. So, what’s the culprit? Sound is sent to your car speakers using wires with electrical signals, which can be easily distorted by other signals from electrical devices like power lines.
Great. Now that we know the why–let’s get to eliminating that music-killing static noise.
The issue is that anything that is capable of generating an electrical field can cause unwanted noise into a car audio system. You would be amazed at the numerous things in your car that can generate electrical fields, ranging from the windshield wiper motor to alternator to the actual sound components of your sound system. They generate different types and levels of static noise. While it may be possible to identify and fix a noise source of a car audio system, the process requires some detective work and patience. The following is a guide on how to get rid of static noise from your car speakers.
Table of Contents
Step #1: Track Down the Source of the Static Noise
The first step to solving the problem is by identifying the cause. There are various reasons that can cause static, including signal degradation as a result of RF interference, mainly due to an unshielded antenna cable or wire too close to the antenna putting out electromagnetic(EM) interference. Sometimes, the problem may be with the radio or accessories. To narrow this down, you need to first turn on your head unit and then set it so that you can hear the static noise.
Step #2: Check Your Patch Cables
RCA patch cables connected to the car audio components are also capable of picking up static noise. To test whether this is what is cramping your style, you will need to detach the cables from your amplifier.
After detaching the cables, insert either side of the spare patch cable into the left and right input jacks of your amp. Turn on both the engine and the audio system.
If the noise disappears, reconnect the cables to the amp and disconnect it from the receiver. If you still hear the noise, then it is your patch cables that are picking up the static noise. If your patch cables are to blame, try re-routing the cables and separate them from the power cable by at least 18 inches. You may have to purchase new patch cables.
Most people tend to use cheaper RCA cables for connecting their components. Inexpensive RCA cables may not have insulation or necessary conductivity for deflecting noise in a metallic body of a high conductive vehicle. Keep in mind that the amount of static noise received by your car largely depends on the loop area’s size.
We like these RCA cables for durability:
Not to get too math-y, the loop area is the distance between the noise center conductor and the outer shield times the length of the cable. You may consider replacing your cable with one featuring a twisted pair design. This gives you a smaller loop area, hence less noise.
If the noise is not originating from the patch cables, then it is likely coming through the antenna. To troubleshoot, first plug the patch cables back into the amp and then unplug your system antenna.
If the noise fades away, then try installing an antenna noise suppressor, which filters the in-line between the receiver and the antenna thus breaking the existing ground between them. If the noise persists even after unplugging the antenna, the static noise may be originating in the amp’s main power cable. Solution? Buy a thicker cable.
Step #3: Pull the Receiver from the Dashboard While Playing a CD
Static noise may also be radiated into your system. This is called radiated static noise. Pull the receiver from the dashboard while playing a CD (props for being old school on those CDs, btw). If the noise fades after pulling the receiver from the dashboard, then the static noise is being radiated into your car sound system.
This can be solved using a magnetic shielding foil, also referred to as Mu-metal. How does Mu-Metal work? In a nutshell, it shields the receiver’s back and wraps components such as your car’s clock that could be radiating static noise into the system.
Step #4: Turn Off Your Car Sound System and Disconnect the Speaker Wires from the Amplifiers
In most cases, static noise comes through the speaker wires. To test the wires, turn off the system and then disconnect the speaker wires from the amplifiers. Now, start your car.
If the noise still persists, then it is likely being radiated into the wires. Now, re-position the wires or shield them using Mu-metal foil wrapping.
Finally, check to ensure that the speaker wires are firmly fitted and there are no breaks in the wire line.
Step #5: Check Your Alternator and Car Battery
If you try fixing the wires but the noise is still there, then the problem could be from the vehicle’s electrical system. In this case, all you need to do is fill your car battery with fluid. If this fails to resolve the issue, then have a mechanic check the alternator and battery. If your ride is old and has not been turned for a long period of time, chances are the static noise is resulting from ignition.
How can you tell if the source if your ignition? Listen for a tickling noise that varies in speed with acceleration. You need to tune-up with shielded carbon-core spark plug wires, resistor-type spark plugs coil and distributor cap.
If the static noise persists, there could be a problem with your car ignition system as far as grounding is concerned. Poor grounding broadcasts ticks to other items like the hood, air conditioner and the exhaust system. Try grounding one of the under-wood components and see if the noise is eliminated.
Step #6: Install a Noise Filter
If the problem is related to the engine noise, then you will hear clicking or whining sound emerging from the speakers. If you establish that the noise only emerge when the engine is on and the noise pitch changes along the engine’s RPM, then probably the problem is on your alternator. The pitch usually varies with the speed of the engine. Usually, most static noise emerges as a result of poor grounding. You need to ensure that the ground wire is firmly connected to the bare metal in case of a static noise.
Sometimes, this kind of static noise in car speakers can be fixed by installing a noise filter.
You can also consider isolating your car amplifier from the car chassis by mounting on the dashboard or using feet or rubber grommets. If that fails, try using different type of patch cables. If the noise is persistent regardless of the engine running or not, then you need to identify the other audio sources that could be causing the noise. Adding Sound Deadening Materials in Your Car can also help you to get rid of those noises.
Out Damn Static, Out!
Static in your ride’s audio system is not something you need to live with. We hope this guide helps you find a way to get rid of static noise in your car speakers for good.