Mest Jet Black
Tourmaline Black Glaze, Masterful Pottery Craftsmanship
Debut of the Hybrid Bone Conduction System
All-New Bone Conduction Crossover Technology
Ultimate Sound Quality, Immersive Unique Melody
Mest Jet Black is a product from the UM MEST series. It continues the series' signature four-driver hybrid configuration while making significant breakthroughs in driver technology and tuning. For the first time, it features a ceramic shell and the newly developed Hybrid Bone Conduction system, along with an innovative bone conduction crossover technology. Listening to the Mest Jet Black is an experience of solemn power and unparalleled sensation.
Mest Jet Black The beginning...
Since its launch in 2019, the MEST series has been widely praised for its outstanding sound and bone conduction technology. After analyzing the strengths and weaknesses of the MEST series, we developed the all-new Mest Jet Black. Mest Jet Black is not just about a change in shell material—it represents a revolutionary advancement in technology. We have refined the sound, particularly the bone conduction component, to achieve a more open and intuitive bone conduction experience. These improvements are evident and have been thoroughly tested by audiophiles in the U.S., Japan, Korea, China, and beyond.
Innovative Material Selection
Following the philosophy of ultimate pursuit and meticulous craftsmanship, we chose a black ceramic shell for the Mest Jet Black. The ceramic shell is delicate, with a smooth, jade-like texture, earning it the name "Black Jade".
The manufacturing process for the ceramic shell and faceplate is extremely complex. It begins with zirconia powder processing, followed by sintering at 1600°C and multiple intricate procedures. The final product undergoes precise manual refinement and high-precision machining to achieve its stunningly refined texture. During the sintering process, the earphone size shrinks by approximately one-third, requiring rigorous verification and testing of design tolerances and final dimensions. Due to the high hardness of ceramic, diamond-tipped tools are necessary for milling, making the final processing stage highly challenging.
Reasons for Choosing a Ceramic Shell:
1. Enhanced Acoustic Performance – The high density of ceramic provides Mest Jet Black with superior acoustic properties, ensuring more stable sound transmission while reducing distortion and unwanted noise.
2. Excellent Sound Isolation – The ceramic shell effectively blocks external noise, allowing for a pure and immersive listening experience.
3. Exceptional Durability and Scratch Resistance – The material maintains its pristine appearance even after prolonged use.
4. Strong Antibacterial Properties – Compared to traditional materials, ceramic is environmentally friendly, recyclable, and hygienic.
5. Smooth, Comfortable Texture – The warm and refined feel of ceramic enhances wearing comfort.
In summary, the ceramic shell of the Mest Jet Black not only elevates its overall aesthetics and texture but also offers significant advantages in acoustics, noise isolation, durability, hygiene, and comfort, delivering an unparalleled experience for users.
Hybrid Bone Conduction System | Bone Conduction Crossover Technology
After six years of research and testing, UM has developed the revolutionary Hybrid Bone Conduction System and Bone Conduction Crossover Technology.
By refining the characteristics of composite balanced armature bone conduction drivers and piezoelectric bone conduction drivers, UM has seamlessly integrated both into a new hybrid bone conduction system. Through crossover technology, each frequency band is handled by dedicated drivers, reducing distortion and enhancing the detail of bone conduction compensation.
· Composite balanced armature bone conduction drivers focus on low and mid-frequency signals
· Piezoelectric bone conduction drivers handle high-frequency signals
Similar to air conduction, Bone Conduction Crossover Technology reduces the burden on a single driver to process the full frequency range, minimizing nonlinear distortion and resulting in a more natural sound. This advancement provides an unparalleled auditory experience.
With the strategic combination of two composite balanced armature bone conduction drivers and one piezoelectric bone conduction driver, UM has successfully pioneered a new Hybrid Bone Conduction System and Bone Conduction Crossover Technology.
Conduction Method: Vibration
Conduction Medium: Composite Balanced Armature Bone Conduction Driver + Piezoelectric Bone Conduction Driver → Human Ear
Key Features:
1. Enhanced response speed and impact of low frequencies
2. Smoother transition in mid-to-high frequencies
3. Jet Black preserves its core strengths while further improving tonal integrity and layering
Driver Configuration
Mest Jet Black continues the MEST series' hybrid driver design, integrating dynamic, balanced armature, electrostatic, and bone conduction drivers. By combining bone conduction technology with traditional air conduction, it delivers a more comprehensive auditory experience.
Below are the two transmission systems formed by Mest Jet Black’s different driver types:
1. Air Conduction System – Traditional drivers generate sound waves that travel through the ear canal and reach the cochlea.
Air conduction driver setup: 1 dynamic driver + 4 balanced armatures + 2 electrostatic drivers.
2. Bone Conduction System – Sound is transmitted directly to the inner ear via skull vibrations.
Bone conduction driver setup: 2 composite balanced armature bone conduction drivers for low and mid frequencies + 1 piezoelectric bone conduction driver for high frequencies.
In this configuration, the dynamic driver is responsible for low frequencies, balanced armatures handle mid and high frequencies, electrostatic drivers cover the ultra-high frequencies, and the combination of composite balanced armature bone conduction for low and mid frequencies with piezoelectric bone conduction for high frequencies ensures full-frequency compensation.
Air Conduction and Bone Conduction FR Curves
UM Dreamy Custom IEM Cable
Dreamy utilizes single-crystal copper that has undergone nearly a year of natural annealing and features a seven-fold pipe structure, providing a more natural sound experience for IEMs.
· Sleeve Material: PVC
· Conductor Material: OCC Copper with Seven-Fold Pipe
· Conductor Gauge: 24AWG
· Number of Conductors: 4
UM Jet Link Custom IEM Cable
The UM Jet Link custom cable is specially developed and designed for the Mest Jet Black. Its black cable jacket and metal components complement the black ceramic shell of the earphones. Made with OCC copper, featuring a seven-core twisted structure and 26AWG four-wire custom wiring, it delivers clear and profound sound.
· Sleeve Material: PVC
· Conductor Material: OCC Copper
· Conductor Gauge: 26AWG
· Number of Conductors: 4
Leather Case
UM has upgraded the leather case for the MEST series, making adjustments in both design and materials. 80% of the case is made from high-end Italian cowhide leather, continuing UM’s signature blue as the primary color. The leather thickness ranges from 1.3mm to 1.5mm, offering high durability, excellent tension, and a vibrant sheen.
The center of the lid features Teal SUEDE Indian goatskin, which has a velvety, soft texture. The interior lining is made of natural navy blue cowhide from Korea, providing great elasticity and durability.
For functionality, the case incorporates a circular Velcro structure, ensuring both convenience and security. Additionally, a built-in pocket allows for easy storage of warranty cards, ear tips, and other accessories.
Specifications
Product Name: Mest Jet Black · Black Jade
Number of Drivers: 10
Driver Configuration:
· 1 Dynamic Driver (Low Frequency)
· 2 Balanced Armature Drivers (Mid Frequency)
· 2 Balanced Armature Drivers (High Frequency)
· 2 Electrostatic Drivers (Ultra-High Frequency)
· 2 Composite Balanced Armature Bone Conduction Drivers (Low & Mid Frequency)
· 1 Piezoelectric Bone Conduction Driver (High Frequency)
Impedance: 12.6Ω
Sensitivity: 106dB @1kHz
Crossover:
· Air Conduction: 4-Way Crossover
· Bone Conduction: 2-Way Crossover
Packaging List
Cable Optional: No Cable / UM Dreamy Custom Cable / UM Jet Link Custom Cable
Carrying Case: UM2 3135C Case
Ear Tips : UM Silicone Ear Tips S | M | L + UM Transparent (Open Tips + Petal Tips) S | M | L
Others: Warranty Card, Cleaning Cloth, Air Mesh Fabric Bag and Notice Card about Cable Choose