TRS Cable Noise: Why It Happens and How To Fix It

If you’re an audiophile, EDM fanatic, or musician, you might be familiar with TRS cables. Or, perhaps you’re working with some new audio technology and experiencing a humming or buzzing noise from your cable. Regardless of your background, TRS cable noise can be a frustrating issue; the good news is there are a few simple solutions.

TRS cable noises can happen because of improper connections, faulty cables, interference with other frequencies, and grounding issues. You can fix the problem by identifying the source, changing wires, removing the interference, or securing the ground connection.

This article will cover the basics of audio engineering, including why you might hear noise from your TRS cable. You’ll also read about how to fix the problem for the best quality sound from any TRS.

What Is an Audio Connection?

Audio connection refers to any system used to record, play, or transfer sound. For example, the headphone connection to your cell phone, your guitar’s connection to an amplifier, or an iPod connection to speakers all use an audio link. 

Essentially, anytime you have a device picking up or outputting sound, that involves an audio connection.

There are two main types of audio connections: analog and digital. For this article, we’ll be discussing analog connections, as these require the use of wires or cables.

What Is a Balanced Connection?

A balanced connection is the preferred method of audio. These cables contain three wires: a ground and two signal wires, one negative and one positive in voltage. This combination of two differently polarized signals cancels out environmental noise. 

Balanced wires are the best option for almost any use because they effortlessly remove buzzing, humming, or other excessive noise.

What Is an Unbalanced Connection?

Unbalanced audio cables only contain the signal wire and the ground wire. With that, the ground wire and signal wire have to use the same pathway, which causes some issues with unwanted noise. 

That ground wire can pick up environmental noise, even from other cables in the room. Because of that, unbalanced connectors are rarely recommended for audio use, though they are usually more affordable.

What Are Balanced and Unbalanced Circuits?

A balanced circuit uses only balanced equipment within the setup, while an unbalanced circuit may have a mix of both. Each element of equipment setup has its own type of connection, so if you use all balanced equipment and cables, the circuit is fully balanced.

However, if you have an unbalanced audio cable in a system with otherwise balanced equipment, the circuit is still unbalanced. The general rule is that unbalanced equipment will always lead to added noise, even if the rest of the system is balanced. 

What Is a TRS Cable?

A TRS cable is a balanced cable used most often to connect balanced equipment, in some cases headphones to a device. The TRS stands for Tip, Ring, and Sleeve cord, referring to the three parts of the balanced cable.

TRS cords look like ¼” (6.35 mm) or ⅛” (3.175 mm) plugs, with each component visible on the outside. The tip is the endpoint of the metal portion. Further down the connector, the ring is separated from the tip with a small black insulating band.

Then, you’ll see the longest part of the connector – the sleeve. The sleeve is a cable shield to protect the delicate parts of the cable. A black insulating band separates each section to prevent the connecting pieces from shorting each other.

Inside the cable, the three components are nestled together, invisible to the eye (unless you cut your cable open – not recommended). Often, TRS cables have this “jack” at both ends to connect to each device.

In other cases, TRS cords have only one jack – most headphone cords are made with a connecting TRS jack on one end that meets the device. TRS cables are balanced, so most people prefer them because they can cancel out any extra noise.

Causes & Solutions for TRS Cable Noise

To find the cause of your TRS cable noise, the best advice is to take it slow. Rather than changing several components at a time, check each element one by one so you can rule them out before moving to the next. 

Always use caution when dealing with electrical equipment to prevent electric shocks and other dangers. That said, the cause of your unwanted noise is likely one of the three following issues.

1. Improper Connection or Faulty Cable

When experiencing noise, the first places to check are the connection and the cable. It seems like a no-brainer, but sometimes the problem is as simple as that. 

Picture it as if your headphones aren’t fully plugged into your phone. You either don’t hear any sound at all, or you hear a patchy, buzzing version of your audio.

TRS cables work the same way. If the jack isn’t fully plugged into the device, you’ll hear the output’s strange noises or affected audio. Otherwise, even minor damage to your TRS cable or jack could affect your audio.

How To Fix

Check the connection and search for any damage along the wires before looking for another possible cause. Of course, if you find a faulty link, try the age-old trick: unplug it and plug it back in. 

If you found damage on the cable, it is likely unsalvageable unless you have expertise in that area. Instead, find an affordable replacement.

2. Interference

Though TRS cables involve a balanced inner system that prevents most interference and unwanted noise, that doesn’t mean they are immune. 

As you read earlier, there are two types of connections: balanced and unbalanced. When a TRS cable is used with an unbalanced circuit, the cable reacts more easily to interference.

How To Fix

Using an unbalanced signal or unbalanced connection is never recommended. However, if you suspect interference is the issue and don’t have the option to rework the circuit or devices, try moving the system to an area with less interference. 

Take wires off the ground and check your devices for environmental noises that the system may have picked up.

3. Grounding Issues

Many audio problems come back to a grounding issue. In addition to background noise in the form of humming, you can also determine if this is the cause in a few other ways. 

Grounding problems can result in weaker signals, shocks, interference, or unwanted noises like crackling or radio sounds. Again, these are more common if you’re using a TRS cable in an unbalanced system.

How To Fix

There are a few general suggestions when it comes to grounding that you can examine and resolve.

• Try to keep all power sources to one spot. Using different power sources comes with the concern of different voltages that may be leading to your problem.
• Avoid a messy tangle of wires on the ground. This is good for your system and organization in general, but it can also prevent ground loops. 
• Go with a balanced system whenever possible. As you’ve read, unbalanced circuits aren’t conducive to noiseless sound, and a mix of balanced and unbalanced will lead to the same issue.

Conclusion

Hearing distracting noise on an audio system is a frustrating and discouraging problem, especially when you can’t find the source. But if you’re dealing with TRS cable noise, there are a few things to rule out before giving up.

• Always use a balanced system when possible
• Check for damage to the cable or connection – in which case you’ll need new equipment.
• The most critical step in solving your TRS cable noise is to only change one element at a time so you can find the exact source of the problem.

Sources

• Cambridge Dictionary: Sound System
• Head-Fi: Audio Connections Between Components — Digital and Analogue
• Indiana University: Chapter Two: Studio Gear
• Santa Barbara City College: Cable: Buying Guide
• Electrical School: Balanced Load
• Audio Engineering Society: Balanced Lines in Audio Systems: Fact, Fiction, and Transformers
• Recording History: How to Use A Balanced Mono PA Cable for Unbalanced Stereo Signals
• University of California, Santa Cruz: Grounding
• College of William & Mary: Chapter 8: Ground Looks and Opto-Isolation