What are In Ear Monitors? – Learn The Benefits!

Many professional musicians rely on this unique piece of device for their performances, but how do they actually work? Do you think it will be a benefit to you as well? Whether you are a serious musician looking forward to a full time career as a performer, or a budding audio engineer who is still learning the ropes, you’ll need to ask yourself – What are In Ear Monitors?

In this article, we will go through the fundamental concepts surrounding the use of this convenient audio monitoring device. Understand the system that it is a part of, and how it benefits musicians or audio enthusiasts. Also learn more about the core components that are crucial in driving in-ear monitors. Are you ready to start? Then let’s not wait any longer!

Custom IEMs

Custom IEMs / Photo by Josiahclanton / CC BY-SA 4.0

Introduction – Who Needs It?

Commonly referred to as “IEMs”, in-ear monitors are devices often used by audio engineers, musicians and audiophiles, for casual or critical music listening. Professional performers also use in-ears in order to hear their own custom tailored mix of vocals and instruments on stage during live performances or studio recording sessions.

The earpiece of an in-ear monitor is often custom fitted for the user’s ears, in order to maximise the level of comfort and also further reduce the amount of noise induced by the environment. In-ear monitors generally cost much more than consumer level listening devices, and are typically utilised in professional audio situations.

In order to understand more about IEMs, we need to first look into the concept of an audio monitoring system, which is a crucial part of any live sound system.

Speaker Wedge

Photo by Robert.Harker at English Wikipedia / CC BY-SA 2.5

Audio Monitoring System

Any sound system that allows the operator to provide a mix of multiple audio sources to performers on stage, is essentially a monitoring system. Conventionally, loudspeakers are used as monitors and are carefully placed on stage, to direct sound towards the performer (usually called wedges). Since IEMs are used in both ears, users are able to hear a stereo mix, if the monitor system is capable of it.

Having a stereo mix adds more depth into the audio quality, as the different sound elements on stage can be panned to each ear. Due to recent technological enhancements, users are now able to incorporate an ambient feature, allowing the attenuation of ambient noise that is filtered by the IEM.

IEMs Musicians

Photo by Lauren Holley / CC BY-SA 2.0

It is important to take note that while IEMs are effective in enhancing the overall accuracy and transparency of the monitor mix and also minimises the overall volume on-stage, performers are now unable to hear the noise coming from the crowd. To remedy this, microphones are placed on both sides of the stage, pointing towards the audience, in order to record some of the crowd noise.

The recorded noise from the audience can then be channelled back into the performer’s in-ear monitors. Live shows that are of a larger scale could incorporate several microphones for the same purpose, spread out across the front of the stage, which could then be routed to a multi-track recording equipment used for broadcasting production, or other uses.

The two core components in an in-ear monitoring system are as follows:

  • Transmitter and receiver
  • Earpieces

Transmitter and Receiver

If you take a look at most professional in-ear monitor systems in the market, they typically incorporate a wireless system in order to send mixes to the IEMs. This wireless system consists of a transmitter and a receiver pack that is worn by the performer. For every monitor mix, there is usually a transmitter and each IEM will always have a receiver.

IEM Receivers

In-Ear Monitor Receivers

The transmitter units are usually designed to output either a single stereo mix or two mono mixes. If a transmitter unit is set to send two mono mixes, then that same unit can be used for two separate mixes. All receiver units can only receive a single mix (either stereo or mono). The wireless audio transmission between transmitters and receivers is done via a VHF or UHF radio frequency.

The general professional consensus is that UHF systems are superior to VHF systems in terms of performance, thus making them more expensive in the market. UHF systems are known to be less susceptible to frequency interference, which enhances its capability in transmitting quality audio signal.


Photo by Kimdrummer / CC BY-SA 3.0


The term IEM actually refers to the earpiece itself, and is at the final stage of the monitoring system’s signal path. The earpiece is usually custom moulded (to fit the user’s ear) in order to provide maximum comfort and allow the sound to be projected directly towards the user’s ear canal. This unique design also provides better noise isolation, which ultimately reduces the level of ambient noise heard.

A custom fit in-ear monitor is typically capable of noise reductions between 25 and 34 decibels. However, keep in mind that this result varies depending on the quality of the fit and length of the canal portion of the earpiece. Manufacturers often offer custom IEMs in a variety of colours, but most of them are clear or in a colour that closely matches the performer’s skin tone.

With enough research, you will find some manufacturers that can place your own custom artwork on to the custom in-ear monitors. IEMs usually use cables with a 3.5 mm stereo jack connector that is plugged into the receiver pack, which is typically clipped onto the belt or clothing of the performer, or placed in a pocket.


Photo by Kansai explorer / CC BY 3.0

You can also look for non-custom IEMs that comes with a variety of foam and silicone tips. These earpieces are designed to be universal and can fit into most people’s ears. They are also generally much more affordable as compared to custom moulded IEMs and thus, suitable for musicians on a tight budget.

We have come to the end of this article. I hope you guys have enjoyed reading and at the same time found this to be very useful in helping you decide if you really need those pricey IEMs!

Do leave comments or questions below, and share this article with your friends!



When I'm not rocking out to great music, I'd prefer to be sleeping on a field on a windy day =)


  1. I am really glad I have found your website. I have friends who have created a band making music at local pubs. Up to now they did it locally but they are asked to participate quite big festival. I know they don’t use any ear protection so I will share your article with them.
    When reading your viewpoints, it seems to me it is not necessarily to have the custom fit in-ear monitor as there are cheaper and not worse alternatives available. But what is your suggestion? Hearing is very important for a human and even more important for musicians so I guess musicians should go for the best solution in this case.

    • Hi Arta!

      The concept of hearing is completely psychological. Some people may find certain sounds to be loud, and others may not seem to think so. There are many professional musicians who do not use IEMs at all, and they seem to be fine with it. In fact, in most cases, they prefer the natural sound of the live concert environment.

      It is really up to the performer to decide, if he/she really needs the IEMs. Your friends could try non-custom IEMs first, to see if it benefits them. If they ultimately decide to stick with it, they could then invest in more expensive custom IEMs in the future.

      Thanks for dropping by!

  2. great post. I can see how an in ear monitor can be extremely helpful to performers on stage. I have been apart of of some performances where monitors are used. I have always found them kind of loud. Do these in ear monitors allow you to keep the volume down a little so you will get less hearing loss form bi loud monitoring systems?

    • Hey Calvin!

      Yes, IEMs will definitely help reduce the risk of hearing loss. Due to its superior noise isolation, as compared to other listening devices, you will be able to hear high quality sounds at lower volumes. Thanks for reading!

      Cheers =)

  3. Thank you I had never heard of iem’s….my son is a musician who writes and records his own music….we have built a mini studio for him but I have never heard him mention ‘in ear monitors ……. I will definitely mention this site to him so he can coma and learn about them.

    • Hello Cambell!

      Your son is welcomed here anytime. If you have any further questions about anything that is discussed here on this site, don’t hesitate to drop by again!


  4. This article helped me decide on using IEM`s when on rehearsal. Your detailed information on how and why other people use the ear monitors for their purposes is very good. Wonderful idea and highly skillful writing i recommend it for anyone who needs help deciding if they should change their sound or how to improve the quality.

    • Hi Philip!

      Yeah, IEMs are also very often used by musicians during rehearsals, and not just at the live show itself. I am humbled by your kind compliments about my writing. I try my best to explain these concepts in the simplest way possible.

      Thanks a lot!

  5. Hi, you definitely taught me something new today. I always wondered why music artists have those ear pieces in their ears (now I know the correct name is “in ear monitors”). I always asked myself the question: Isn’t the music loud enough for them to hear? I see now that it’s to hear the finer details of the music better. You have really given a good and understandable explanation on the topic of IEMs, their use, what they do , how they work and the types available. Keep up the good work!

    • Hey George!

      Thanks for taking the time to read the article. Its great to know that you now have a better understanding of IEMs. Do come back again soon!

      Cheers =)

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