FAudio Mezzo LE Review

Today we are taking a look at the $1,900 USD FAudio Mezzo LE (Limited Edition) Universal In-Ear Monitors.


Disclaimer: The FAudio Mezzo LE was sent to us by MusicTeck for this review, free of charge. I only covered the import taxes and fees. As always, I’m here to give you my honest opinion on the product.


Specializing in the research and development of audiophile in-ear monitors, FAudio has been a well-known company in Eastern markets since 2014. The company is based in Hong Kong. If you are an audiophile living in Europe or the Americas, you may not have heard of FAudio.

This is where we come in. Today we have a very special product, the Mezzo LE, limited to 588 sets worldwide, which is one of FAudio’s most impressive products.

I would like to point out that all of FAudio’s in-ear monitors are handcrafted to the finest detail at their headquarters in Hong Kong. Therefore, each set comes with a unique pattern. FAudio has been developing Mezzo LE for more than 3 years and recently the monitors have been released internationally. The Mezzo LE retails for $1900 USD. It can be purchased from MusicTeck.

Let’s take a detailed look at the configuration.

FAudio Mezzo LE Limited Edition

Let’s start by hearing the development story directly from FAudio.

“Back in early 2019, we completed the basic product design of Mezzo and presented the first engineering prototype at the Autumn Headphone Show in Japan. Three years later, we have made countless changes to Mezzo, including adding new unit designs, adding personal tuning features, and more, so that we can meet you in the most powerful and perfect position after all the adjustments.

I would like to share some of the design philosophies of Mezzo. This time we have taken inspiration from the instruments and incorporated the basis of their design into our product concept, because, in a wide variety of songs, both ancient and modern, the instruments play a role in advancing the music, highlighting the rhythm and atmosphere, and are an important element of a song. The tuning design of the Mezzo circuit was inspired by the design of electric guitars!

The Stratocaster, designed by Leo Fender, Bill Carson, George Fullerton, and Freddie Tavares, was first released in 1954 and is a monumental work. The Stratocaster is one of the greatest musical inventions in the history of human music, and in my opinion, one of the greatest inventions in the history of music.

The Stratocaster is one of the very few guitars in the world that is recognized by guitarists of all genres and is the most widely used in different musical applications. Such a guitar has had a great influence on rock, blues, and pop music history, and even the entire history of guitar design and manufacturing, and is the most dazzling, influential, and even the greatest in the guitar world. Of course, this part is a bit personal, after all, I’ve been addicted to the toxic sea of guitar collecting for the past 20 years, and I love to study everything about this wonderful creation! Haha!

The Single Coil pickup design used in the Stratocaster allows the musician to fine-tune the tone to suit his playing style by switching the circuit or adjusting the potentiometer (aka Switch) to achieve a distinct and varied tone: this is the inspiration for Mezzo’s custom tuning feature. And I can tell you responsibly that Mezzo’s tuning is one of the most versatile and adaptable of any similarly designed product on the market, and it is not limited by one type of music while maintaining an extreme balance!

The Mezzo’s crossover circuit has the longest and most complex tonal adjustment time of any product we have released in the past seven years. In this extremely sophisticated crossover circuit, to minimize distortion and tonal differences in unit use, we used a PCB board as the core of the entire autotune function for the first time, and tested a variety of different brands of capacitors and resistors so that Mezzo could deliver the most suitable and extreme sound experience in each autotune mode for each type of music. Let me explain in detail the characteristics and various applications of each of the Autotune modes! -K”

As you deduce from FAudio’s fantastic article, they are very passionate about Mezzo LE and it makes a lot of sense that they are launching the product on the 7th anniversary of their company. It is clear that the R&D of the product has taken considerable time and effort.

They also state that the R&D process has been supported by the feedback they have received from users at most of the audio exhibitions they have participated in since 2019.

Since I think your curiosity about the configuration is at an all-time high right now, let’s take a deep dive into the technical details of the Mezzo LE.

Inside each shell of the Mezzo LE contains two balanced armatures, a piezoelectric tweeter, and a modified version of the highly acclaimed 10mm dynamic driver previously used in FAudio’s Major IEM. One of the BAs is tasked with mid-high frequency reproduction, while the other is a full-range driver. The 10mm double-layer diaphragm dynamic driver is responsible for the optimal reproduction and transmission of the lower frequencies.

The company states that the piezo driver has an impact on the entire spectrum, making a major contribution to fundamentals such as tone enhancement, spatial restoration, and texture.

Additionally, the Mezzo LE combines all these drivers with in-house patented technologies to provide a flagship tuning all-around. The Mezzo LE uses 2 such technologies. The “T.C.T” and the “T.B.A.C”. Here’s how FAudio explains the details of these technologies;

True Crossover Technology (T.C.T) is an advanced and unique crossover technology that compensates for the transition point of the frequency band through a full-frequency driver, resulting in a smooth, supplementary tri-band transition without creating phase distortion. This technology thoroughly integrates the sound of the drivers and provides improved sound coherence, while keeping the drivers in optimal working condition and providing higher accuracy of the final signal.

The T.B.A.C is a triple chamber designed specifically for dynamic units, which can further enhance the transducer efficiency of the dynamic unit by eliminating the unstable frequency response and excessive airflow generated by traditional dynamic units. This time, we have used Major’s moving coil unit to strengthen the structure of the low-frequency restoration part, so we have designed a new T.B.A.C acoustic solution for Mezzo to better integrate into the whole space structure, and to maintain the smooth airflow of this moving coil unit under the high-intensity operation.

Chamber 1.

Provides a constant supply of air to the unit, enhancing the transmission efficiency of the upper midrange and treble, and at the same time making the layers of the double diaphragm more distinct.

Chamber 2.

The metal structure enhances the rigidity of the entire unit, carries away excessive harmonics, and regulates the air intake through the rear chamber air holes to achieve a powerful tuning effect.

Chamber 3.

Specially designed to accommodate 10mm moving coils, made with high-precision 3D printing technology and metal coating, the front air holes effectively discharge excess air and reduce some of the excess sound pressure, providing a smooth channel for moving coils to transmit sound waves and minimizing the sound pressure generated by low-frequency waves, greatly increasing the comfort of long-term listening.

The Mezzo’s autonomous tuning design did come relatively late. One of our goals was to incorporate the multi-pickup switching design of the legendary electric guitar Stratocaster into this product, and bring the most distinctive tuning style to the user!

In addition, after studying various tuning design possibilities, we found that the conventional tuning circuit mechanism may affect the final sound phase and frequency response curve, so we conducted quite a long period of testing and parameter adjustment, and tried various solutions to test its frequency response, and finally achieved a more targeted tuning effect based on the actual listening experience. This is where we spent most of our time in the development process.

The crossover circuit is more complex than any other pair of headphones in the past, and by using the patented T.C.T and T.B.A.C technology, the output of the full-frequency moving iron unit is compensated for different tuning modes to maintain the linearity of the entire frequency response curve and the smoothness of the three frequencies, so that different tuning combinations can perform well in terms of quality and coherence.

Mezzo offers three bands of frequency response compensation;

Tuning Switch No. 1 – Low Boost

Tuning Switch No.2 – Mid Boost

Tuning Switch No.3 – High Boost

Listening suggestions for each tuning mode are provided below.

Switches All Off – Natural HiFi (Vocal, Soft Pop)

Switches All On – High Gain (Rock, Metal, Animation)

1+2 mode (Dance, Hiphop, EDM)

2+3 mode (Pop, R&B, Soft Rock)

1+3 mode (Classical, Gaming, Movie) “

So yes, this pretty much sums up the majority of the magic that went inside each shell of this enchanting green monster. Feeling confused? Don’t worry, in the section where we talk about the sound quality of the Mezzo LE, we’ll combine it with all kinds of sources, check out its synergy, compare it with various IEMs, and experiment with different cables so you won’t have to.


The review continues on the next page. Click here or use the jump below.

Page 1: FAudio, Mezzo Limited Edition

Page 2: Packaging & Accessories, Tone-Master Cable, Design, Build & Fit

Page 3: Tuning Switches, Sound, Technical Capability, Source Selection, Comparison, Last Words

4.4/5 - (262 votes)

Long time Tech Enthusiast, an ambitious petrol-head, Yagiz likes his gadgets and always finds new ways into the tinkerer's world. He tries to improve anything and everything he gets his hands onto. Loves an occasional shine on the rocks.


  • Reply November 1, 2022

    Samuel Williams

    Great read, thank you. I have a Monarch MK II and I plan to upgrade to this one.

  • Reply November 1, 2022

    Lincoln Asparagus

    Fantastic review thank you yagiz. I checked the Music teck website to purchase Mezzo but it is out of stock.

  • Reply November 14, 2022

    Jorge Costa

    How good is this set with prog rock, metal and alternative rock?

    • Reply December 22, 2022


      Fantastic, just listening to Procupine Tree (Athens 1995) and sound is like beeing live at the concert. I do not listen to metall so not able to judge on this.

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