Understanding the Headphone Jack: Types and Uses Explained

Introduction

Headphone jacks are used to connect audio devices such as headphones, microphones, and speakers. In other words, 3.5mm or 6.35mm jacks facilitate the input and output of sound in various audio equipment and mobile devices. Read more to find out their uses and how to integrate them into a Geekom mini PC.

A jack socket, often called an audio or telephone socket, is a cylindrical connector used to transmit audio signals. You can find them in headphones, microphones and other audio equipment. As such, these sockets link audio devices together, enabling audio systems to function.

Jacks are essential for connecting devices. Basically, they provide a standard and versatile interface for inputting and outputting analogue audio signals.

What are Audio Jacks and Headphone Plugs?

Audio jacks and headphone plugs are essential components in the world of audio equipment, enabling the seamless transmission of audio signals between devices. An audio jack is a port that receives a headphone plug, allowing users to connect their headphones or earbuds to a device and enjoy high-quality audio. The headphone plug, on the other hand, is the male connector that inserts into the audio jack, establishing a secure connection for audio signal transmission.

These components are ubiquitous in various audio devices, from mobile phones and laptops to professional audio equipment. The audio jack ensures that the audio signals are transmitted accurately, providing a reliable connection for both analog and digital audio signals. Whether you’re using wired headphones or connecting to an audio mixer, the headphone plug and audio jack work together to deliver clear and uninterrupted sound.

History and Evolution of the Jack Plug

The 6.35 mm jack, a common audio connector, was first used in 1878 for telephone switchboards.

The 3.5 mm plug is a smaller, portable version of the 6.35 mm plug. It was initially designed for telephone switchboards. It was later popularised by transistor radios and devices such as the Sony Walkman.

Evolutions and Standards (3.5 mm, 6.35 mm)

Generally speaking, a jack plug is used to connect several audio devices, including guitars, keyboards, loudspeakers etc. The 6.35 mm has evolved into different sizes and configurations, like the 3.5 mm for portable devices. To connect a device with a microphone, you need to use standard 3.5 mm audio sockets. In TRRS plug configurations, an additional conductor is used to transmit the mic signal, which is essential for devices like smartphones and gaming consoles. Then you need separate sockets for audio output and audio input.

In addition, for audio on a mini PC, you can opt for a combined socket that supports both. Some devices have a single 3.5 mm socket that supports both audio output and microphone input. This is a TRRS (tip-ring-ring-sleeve) or 4-pin socket.

Transition to Wireless Technologies from Wired Headphones

Using a wireless jack (Bluetooth adapter) enables wireless audio and device connectivity. This offers convenience and flexibility but can also introduce potential problems. These can include degradation of sound quality, latency and interference with other wireless devices.

For audio on a mini PC, wired connections (3.5 mm sockets) generally offer lower latency. In this case, signal quality is more consistent and sound quality better than wireless options. On the other hand, wireless offers convenience and the absence of cables.

Types of Jack Sockets

Jack plugs, often 3.5 mm, are the universal standard for connecting audio devices. This simplifies the process and guarantees compatibility. Alternatively, for professional and music applications, the 6.35 mm is known for its robustness and reliability.

3.5 mm headphone jack plug

Mono (TS) 3.5 mm jacks have two contact points and are used for single-channel audio. On the other hand, 3.5 mm stereo (TRS) jacks have three contact points for two-channel audio, with each ring conductor supporting an additional audio channel.

Advantages：

• Jack sockets are a widely used standard, ensuring compatibility with a wide range of audio devices.
• The plugs are simple to use, requiring no special drivers or software. This makes them easy to connect and use.
• Headphones and other audio devices with headphone jacks are generally more affordable than those with digital connections such as USB-C or Bluetooth.
• The jacks use the device’s internal sound card for analogue audio. So, there’s no need for a separate digital-to-analog converter (DAC).

Disadvantages

• The analogue nature of jack connections can be susceptible to interference from other devices or electromagnetic fields.
• With the rise of USB-C ports, jacks don’t allow you to charge and listen to music simultaneously.
• Jack cables can be bulky and prone to tangles, especially with multiple devices.
• Analog audio signals can be susceptible to noise and interference. In short, this can affect audio quality.

6.35 mm jack socket

This jack is commonly used to connect headphones and speakers – basically, music equipment. These include mixers, amplifiers, effects units and guitar or bass equipment.

Compared to 3.5 mm, it is a standard connector for professional audio equipment.

Modern combo and alternative jacks

The combo connector (XLR/TRS/P10/phone) is a versatile audio input or output connector. It combines an XLR and a 6.35 mm (TRS) jack plug in a single housing. As a result, it offers great flexibility for different audio configurations.

Components of Audio Jacks and Headphone Jacks

Audio jacks and headphone plugs consist of several key components that work together to facilitate audio signal transmission. The audio jack typically features a female connector with a socket, while the headphone plug has a male connector with a tip, ring, and sleeve (TRS) configuration. The tip and ring contacts are responsible for transmitting the left and right audio channels, respectively, while the sleeve serves as a common ground reference voltage or return current for the signals.

The headphone plug also features insulation bands that separate the conductors, ensuring that the audio signals are transmitted cleanly and without interference. The number of conductors on the headphone plug can vary, with common configurations including two, three, or four conductors. The size and shape of the audio jack and headphone plug also play a crucial role in ensuring a secure and reliable connection.

These components are designed to provide a stable and high-quality audio output, whether you’re listening to music on your stereo headphones or using professional audio equipment. By understanding the components and their functions, users can better appreciate the technology behind their audio devices.

Compatibility and Connectivity of Audio Signals

While 3.5 mm jacks are more common for portable headphones, 6.35 mm jacks are still used for professional headphones. In particular, 6.35 mm jacks are used in studio and live sound applications. They can be mono (with two contacts) or stereo (with three contacts).

6.35 mm also connects speakers to amplifiers in DJ and PA systems.

1. Compatible Devices

3.5mm jacks are commonly used for portable devices such as smartphones, tablets, and other mobile devices. 6.35mm jacks are used for professional equipment such as amplifiers and studio equipment.

2. Use with Mini PCs

Characterized by its symmetrical, oval shape, the USB Type C plug has become a standard for modern devices. In addition, its compact size and reversible design have contributed to its popularity. This jack is also an advantage for mini-gaming PCs. It supports high-speed data transfer, charging and audio transmission.

So, these jacks adapt to new device technologies and features.

3. Adapters and Converters

Although USB and Bluetooth offer digital audio connections, headphone jacks are better for audio applications. Some older devices may have separate jacks for headphones and microphones. Mini PCs, on the other hand, generally use a single, combined jack. The latter supports both functions using a different type of plug.

Here’s a video on YouTube to better explain the jack plug:

Common Problems and Solutions

Jack sockets are primarily used for basic audio playback and do not offer advanced features. For example, they do not offer digital signal processing or high-resolution audio codecs. Additionally, these jacks can become loose or damaged over time, resulting in intermittent audio issues.

1. Unstable Connection or No Sound

Due to wear, dirt, or a jack incompatibility, the connection can be unstable in a mini PC. To resolve this type of issue:

• Check that the headphone jack or headphone plug is not visibly damaged;
• Gently clean the port with a small brush or compressed air to remove debris;
• Make sure the volume is turned up and not muted;
• Try another cable to make sure the problem is not with the cable itself;
• Make sure the cable is fully inserted into the AUX port. 

2.Jack Plug Wear and Durability in Audio Equipment

Factors contributing to wear are frequent plugging and unplugging. To prevent wear and promote durability, use a can of compressed air or a soft brush to clean it gently.

3. Troubleshooting

If you are having trouble getting your microphone to work on a mini PC, there are a few things you should make sure of:

1. Are you using the correct outlet?
2. Is your microphone adequately connected;
3. Do you configure the computer’s audio settings correctly?
4. You should also clean the jack and replace any faulty cables and accessories.

The Future of Audio Jacks and Headphone Plugs

As technology continues to evolve, the future of audio jacks and headphone plugs is likely to be shaped by advancements in digital audio signals and wireless connectivity. While traditional analog audio jacks and headphone plugs will likely remain in use for the foreseeable future, there is a growing trend towards digital audio connections such as USB and Lightning.

Wireless audio technologies like Bluetooth earbuds and headphones are also becoming increasingly popular, offering users greater convenience and flexibility. However, it’s worth noting that wired headphones and audio equipment will likely continue to be preferred by audiophiles and professionals who require high-quality audio output and low latency.

In the world of professional audio equipment, audio mixers and audio interfaces will likely continue to feature a combination of analog and digital audio jacks, allowing users to connect a variety of devices and equipment. The phone jack, in particular, will likely remain a staple in the music industry, with many musicians and audio engineers relying on its reliability and versatility.

Ultimately, the future of audio jacks and headphone plugs will be shaped by the needs and preferences of users, as well as advancements in technology and innovation. As the audio landscape continues to evolve, it’s likely that we’ll see new and exciting developments in the world of audio jacks and headphone plugs.

Conclusion

The 3.5 mm and 6.35 mm jacks facilitate both audio input and output in a mini PC. They mainly handle analogue audio signals. These are traditional sound transmission methods suitable for a wide range of audio devices. So, it’s beneficial to understand their usefulness or how to integrate them into your device!