How Do Headphone Jacks and Plugs Work?

If you are wondering how do headphone jacks and plugs work? You most probably have some operational issues. As with most things, headphone jacks work great until they don’t work anymore. So are you going to fix them or buy new ones?

Knowing how headphone jacks and plugs work gives us a better understanding when we get issues that affect the sound flow into our headphones.

So, let’s go through my simple guide to headphone jacks and how they work…

Contents

How Headphone Jacks Work – The Basics

The basics are very simple, headphone plugs are female connectors, while headphone jacks are their male counterparts. The headphone plugs connect with the jacks to create an electric flow of audio signals.

The types of wiring, microphone functions, and connectivity can change with the different configurations of plug-to-plug, jack-to-jack, and jack-to-plug. So we must first delve into the differences between a headphone plug and a headphone jack.

The Main Differences Between Headphone Jacks and Plugs

If you look at the male and female headphone jack and plug connectors, they look similar to the naked eye. However, there are a few differences that you need to be aware of. The connectors we are talking about are located on the ends of the cable.

What’s the difference between headphone jacks and plugs?

The headphone jack is the female part, and the headphone plug is the male part. Headphone plugs come in many sizes, such as 2.5mm, 3.5mm, and 6.35mm TRS audio connectors. The headphone jack is routinely a 3.5mm cable. The plug connects to the audio device while the jack connects the cable to the headphones. Those are the basic fundamental differences.

How to Connect Headphone Jacks with Plugs

Not all headphone plugs and jacks are compatible with each other; they need to match to be compatible. Headphone plugs and jacks need to be the same size and have the same wiring to work properly. However, there is some wiggle room with the wiring compatibility.

Headphone jacks and plugs are individual connectors that have several conductors, usually between two and five. For plugs and jacks to work together, these conductors have to be set to the correct format to adequately transfer the audio data from one to the other.

Wired headphones are transducers that can convert a signal from a certain format to another one. These are always analog audio signals that are carried electrically in AC voltage through wires.

Carrying audio signals via analog…

The headphone plugs and jacks use their conductors to send the audio signals along the cable. This is why it’s so important to align the conductors between the plug and jack so it can carry the audio to the headphones via its wiring scheme.

One of the main issues you will have is you cannot physically see the connections between the jack and plug unless you completely strip the jack and cable. But basically, this is how a headphone jack and plug work together to send audio to the headphones. They act as a conduit for electrical current from the audio source to the headphone device.

Headphone Plug and Jack Sizes

Headphone jacks and plug connectors come in many different sizes. It’s always important to know your options when you need to connect the two to your headphones. Please see a list of headphone plug and jack sizes below.

2.5mm (3/32 in)

This 2.5mm jack or plug is not very common in the modern audio stratosphere. However, this connector is still used to connect two-way devices such as walkie-talkies and even some old VCRs. This is a typical unbalanced mono TS (tip-sleeve) connection. Or it can also be a TRS (tip-ring-sleeve) connector.

3.5mm (1/8 in)

This is the most commonly used connector, especially with wired headphones. But you will also find this jack on old smartphones, laptops, tablets, some mixing consoles, and some tape recorders. These connectors can be either unbalanced stereo TRS (tip-ring-sleeve) or unbalanced stereo and mic, which is a TRRS (tip-ring-ring-sleeve) type.

4.4mm Connector

One of the newest connector types. This type is usually called the “Pentaconn” and is largely compatible with Sony and some HiFi devices. These connectors are balanced stereo that comes equipped with TRRRS (tip-ring-ring-ring-sleeve) varieties.

6.35mm (1/4 in)

These large jacks are predominantly used in recording studios and for electric instruments. If you’ve seen the big fat jacks that go into electric guitars, then you have seen this connector. Usually wired as unbalanced mono TS (tip-sleeve), although when this jack is used for headphones, it’s normally wired as an unbalanced stereo TRS (tip-ring-sleeve).

Don’t forget size adapters…

The 3.5mm and the 6.35mm connectors are easily the most commonly used in the world of audio and headphone connections. Therefore, these are the ones you will come into contact with the most. However, there is the option to use a size adapter.

These come in standard jack-to-jack and plug-to-plug variants, and also for plug-to-jack and jack-to-plug combinations. You can cross-connect many different-sized jacks and plugs with adapters.

Understanding Headphone Jack/Plug Wiring Schemes

Now that we know the answer to How Do Headphone Jacks and Plugs Work? We need to take a basic crash course in headphone jack/plug wiring. Entire guides have been written on wiring schemes, but there are a few essentials you need to understand.

We have already briefly discussed the tip, ring, and sleeve connectors. Usually denoted by their abbreviated capitals such as T (tip), R (ring), and S (sleeve). These are the standard terms used to explain the different conductors that are on the connectors.

We also already talked about how the conductors need to be aligned for the connection to work. Each of these is an individual wire in the cable that carries the audio to the headphones. So, let’s take a brief look into wiring standards for headphone jacks and plugs and the type of audio that is transferred.

Stereo and Mono Audio Wiring

Most modern headphones over the past 50 years have been wired to accept stereo sound. It’s been the standard in music for eons. However, did you know that there are still some headphones that only accept mono audio? This is where it might get a bit technical.

For mono sound, you will need at least two conductors. This will be one signal wire and a return wire, which also acts as the ground. This is a very simple TS (tip-sleeve) connector. If we need to wire for stereo sound, we need at least three conductors. These will be the left channel audio wire, the right channel audio wire, and the return/ground wire.

But please remember that it’s common for both mono and stereo headphones to have more conductors than they need. This is for microphone integration or to balance the transfer signal.

What is Balanced and Unbalanced Audio Wiring?

Most modern wired headphones have unbalanced audio, although there are exceptions. Unbalanced audio wiring features one wire for signal and another wire for return/ground.

These two wires work together to form a circuit that ensures the audio signal reaches the headphone’s driver. Unbalanced audio is perfect if using short headphone cables but can deteriorate with longer ones.

Balanced Audio wiring uses two signal wires…

One of the wires carries the positive pole signal, while the second wire carries the negative pole signal. This balanced audio wiring creates a stronger signal with less interference, which makes it better for long cables.

It’s important to mention that stereo headphones need two unbalanced or balanced audio signals for their two headphones drivers.

Highly Recommended Wired Headphones and Jack/Plugs

Understanding the basics of wiring and how headphone jacks and plugs work will help you to make the right product choices. So, check out these highly recommended wired headphones…

Need a pair of quality Headphones or more helpful info?

Then check out our in-depth reviews of the Best Headphones Under $100, the Best USB-C Headphones, the Best Wireless Headphones for TV, the Best Headphones Under $20, the Best Headphones with Microphone, or the Most Comfortable Headphones on the market in 2023.