Jomo Instinct Emerald Review – Force of Nature

Pros –

Comfortable and visually charming shells, Excellent included cable, Bold yet meticulously controlled bass, Excellent treble fine detail retrieval, Powerful and clear midrange, Top class soundstage expansion

Cons –

Lacks separation, Mid bass tuning is somewhat tubby, Not the most genre versatile tonality

Verdict –

The Instinct is a creation of warmth, power and space that epitomizes the subjective nature of the hobby atop marvellous driver and acoustic design.

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About Jomo –

Jomo Audio is a Singaporean audio company who’ve been making high-end IEMs for over a decade and a half. Joseph, the man behind the brand, has a background in electrical engineering and extensive experience with audio mixing and broadcasting. Starting out as an enthusiast, Joseph had humble beginnings re-shelling and repairing IEMs from local audiophiles which opened the opportunity to develop his own models. Over the years, Jomo reached the international market and has become one of the most renowned brands in the high-end boutique market. Jomo now works out of a medical-grade lab with professional tools and relations with Knowles, Sonion and Egger. They have access to the latest technologies including 3D scanning, CAD and printing. Jomo has continued to push the boundary of technology since.

Introduction –

Following the success of the Flamenco, Jomo then chose to focus more on innovative driver types and designs. This is exemplified by the Alpha Ti LE IEM which sports a complex 9-driver tribrid setup comprised of a dual DD woofers, 6 BA drivers and a piezo tweeter. Shortly after, Joseph launched the Impulse Ti and Instinct Emerald which both use a similar driver platform. Given the limited units available and high asking price, I asked Joseph about his 3 new flagships and how they compared. Joseph expressed that the three models all share a very similar structure and setup but offer different flavours of sound mostly due to the difference in dynamic driver diaphragm and shell materials. The Instinct offers a slightly more V-shaped sound than the Alpha Ti with a stronger bass response and slightly brighter top-end. It also sports a slightly more complex 5-channel cross-sync Uniphase passive electronic crossover.

The Instinct is available for $2999 at the time of writing. You can read more about it and secure one for yourself at Jomo Audio!

Disclaimer –

I would like to thank Joseph very much for reaching out to organise a review of the new Instinct Emerald. All words are my own and there is no monetary incentive for a positive review. Despite receiving the earphones free of cost, I will attempt to be as objective as possible in my evaluation.

Contents –

• Page 1: Intro, Unboxing, Design
• Page 2: Sound and Source Pairings
• Page 3: Comparisons & Verdict

Specifications –

• Drivers: Dual custom 10mm Ti DD, 6-BA, 1 nine-layer PZT
• Crossover: 5-Channel C.S.U
• Frequency Response: 20 Hz – 80 kHz
• Impedance: 9 ohms

Behind the Design –

Dynamic Driver Chamber Unit

The Instinct Emerald uses a dual 10mm dynamic driver woofer unit to deliver its powerful bass output. Each driver sports an ultra-thin titanium diaphragm and has been placed in a cone-to-cone configuration. The dual woofer array lowers distortion, increases efficiency, and also effectively achieves the bass response that would be possible in double the housing volume which improves space efficiency. Jomo achieves this using a brass CNC-machined airflow control chamber that controls venting in front of the dynamic drivers allowing fine-tuning of the bass response alongside acting as a waveguide to ensure phase coherence.

Six Midrange Balanced Armature Array

Midrange and high frequencies are handled by six balanced armature drivers. Joseph doesn’t state where they are sourced from, only that they are high-precision units. Visual inspection shows a 4 + 2 configuration with the quad-driver stack offering a visible magnet yoke. This suggests the use of a modern Knowles component.

9-Layer PZT Tweeter

Piezo drivers had a popularity spike several years ago but have since disappeared into relative obscurity. Jomo is bringing it back, implementing a 9-layer piezoelectric ultra-high frequency driver. PZT drivers function by using a ceramic material that actuates/moves when an electrical current is applied. While they offer a narrow frequency range, they can deliver excellent efficiency as they convert electrical energy directly into mechanical energy with no friction elements that may lower resolution. The downside is heat generation which is addressed by increasing the layer count. This increases surface area and efficiency and improves heat dissipation. Greater heat dissipation allows the driver to actuate at higher frequencies without suffering from heat damage, resulting in extended and low distortion treble.   

5 Channel C.S.U Crossover

Jomo’s complex driver array is united by a 5-channel C.S.U (CrossSync Uniphase) passive electronic crossover network. Adding extra channels allows for greater fine-tuning of the IEM’s frequency response and also better ability to correct phase. This system works in conjunction with sound tube length and driver positioning in addition to cross-over component values to achieve phase coherence thereby improving resolution and minimizing distortion.

Adrenalin MK II (4W)

The Instinct comes with Jomo’s Adrenalin MKII upgrade cable out of the box, which is an updated, 4W variant of the cable that came on the GT600. It’s a 21AWG OCC silver-plated copper cable with high-precision CNC machined metal components hand-crafted in-house at Jomo.

Unboxing –

In my chats with Joseph, we’ve enjoyed talking about our mutual love of JDM cars. I enjoy how Joseph has woven this into his IEMs and this is exemplified by the unboxing experience on the Instinct in the form of a carbon fibre textured case. The case offers a metal frame, hinge and clasp assembly alongside silver Jomo branding. Opening the box reveals a laser-cut foam inlet that holds the accessories snugly. The button-clasp carrying case first draws focus with its authentic leather construction and aroma. Within are the IEMs within a drawstring pouch that keeps each shell protected during transit.

In addition, the right side of the box houses a microsuede cleaning cloth, Jomo ear tip box and assorted stickers too. The Adrenalin MKII cable is provided within a green satin pouch and demonstrates excellent quality that rivals many custom cables. However, it is not modular at either end. In terms of ear tips, the Instinct comes with 3 pairs of dual-flange silicone tips and 3 pairs of hurricane silicone tips. These are a good choice given the earphone has quite a warm and bassy tuning, foam tips may have provided too warm of a sound.

Design –

As opposed to its siblings, the Instinct has a medical-grade resin shell which Joseph says contributes to the sound tuning differences between the 3 flagships. True to its name it comes in a vivid emerald green adorned with precision milled bronze faceplates. The shells are covered in a flawless high polish finish that is super slick and easy to clean. Unlike many modern 3D printed shells, the Instinct is not resin-filled which perhaps provides greater air volume for the dual-woofer system to work with, working in tandem with a small vent located near the 2-pin connectors. The milled faceplates give the earphone heaps of depth and a premium aesthetic. There are no bubbles or imperfections miring this impression and the resin construction is overall solid yet lightweight if not as exotic as its metal-clad counterparts.

As aforementioned, the Instinct uses 2-pin connectors however, unlike most, Jomo has implemented a spring-loaded tensioner system that improves reliability and service life. I’m a huge fan of this as not all 2-pin connectors are made equally with some being a little larger than others. This can stretch out the connectors leaving them loose when used with other cables. Jomo and MMR’s designs both use these connectors and I’ve never had any such issues, maintaining a reliable connection after countless cable swaps. This has made them my go-to choice for cable reviews and comparisons. The cable itself also inspires, with the Instinct coming pre-equipped with Jomo’s Adrenalin MKII upgrade cable right out of the box.

The Adrenalin MKII is an OCC SPC cable with a 4-wire configuration. It certainly looks the part with stunning silver conductors beneath compliant transparent TPU insulation and milled gunmetal connectors. There’s a good amount of strain relief and comfortable pre-moulded ear guides. The cable has no memory, so it coils easily for storage and resists tangles well. It also comes with a 4.4mm balanced termination out of the box which is a nice addition. The overall quality matches many midrange aftermarket cables including the sound performance. I used the Instinct for a few cable reviews prior to this article and noted that the stock cable was both a good sonic pairing for the Instinct and that it made a notable impact on the sound compared to standard OFC cables.  

Fit & Isolation –

With a 9-driver configuration and two large dynamic drivers inside, the Instinct is on the larger side for an IEM. However, the dimensions are all reasonable and the internal layout has been well-considered to uphold ergonomics. Chiefly, the shells are smoothly formed, and the height and length are no greater than most IEMs. Only the depth has been increased to accommodate the driver setup and as a result, they protrude slightly more from the ear. However, they didn’t contact much of it during my testing due to their rounded profile and two small divots that relieve pressure on the tragus and antitragus, thereby mitigating hotspot formation.

They are still not a good choice for those with especially small ears, that said. As the shells are relatively light and offer an over-ear fit style, stability remains excellent with no issues during my testing. The protruding and well-angled nozzle also aids a strong seal while the vented design relieves pressure, improving wearing comfort and ensuring that no driver flex is apparent. Despite this, the venting is minimal, so passive noise isolation is quite good and above average among vented IEMs. With foam tips, the Instinct isolates very well and is easily adequate for commute and daily use with silicone tips too.

Next Page: Sound Breakdown