Brise Audio IBUKI

A Fresh Breath of Air!

PROs: modified IEMs design from Fugaku with a detachable cable and the freedom to use any source, updated 9-driver tribrid config (2DD/5BA/2EST), expanded soundstage and imaging, very powerful, deep, visceral 2xDD bass, natural, detailed mids, crystal-clear treble, premium custom cable, and premium leather case.

CONs: price, source and eartips pair-up dependency, detachable cable attachment at the bottom.

Brise Audio IBUKI was borrowed from Musicteck for testing and analysis in this review.

Manufacturer website: Brise Audio. Available for sale through authorized retailers, including Musicteck.

Intro.

Code-named “BEP-001”, which was just a placeholder name until the official unveiling, the prototype of IBUKI IEMs made its debut at Musicteck tables during the recent CanJam NYC ’26 show. It was referred to as a prototype because the final version was mentioned to have an updated shell material, a different connector, and, as we learned later, a slightly updated tuning. I was able to borrow BEP-001 after CanJam and wrote a detailed First-Look review, assuming the final version changes will be mostly cosmetic rather than in tuning. But as it turned out, the Brise Audio team collected a lot of feedback from the customers and retailers, paying particular attention to those who craved the tuning in the direction of Fugaku. After receiving the IBUKI loaner from Musicteck and spending a few days with it, with BEP-001 still fresh in mind, I decided it was time to start working on the IBUKI write-up.

As I mentioned in the BEP-001 review, to follow Brise Audio’s new product announcements, you need to be familiar with their design evolution. Well-known for high-quality, original premium wires, they first decided to build a portable reference amplifier as an evaluation testbed for cable development. That is how the original TSURANAGI (Tsu) was born, later evolving into Tsu v2 with a more IEM-friendly volume-curve adjustment. Then, Brise Audio surprised everyone with the announcement of FUGAKU (Fu), an all-in-one, transportable, compact audio system — a fine-tuned, custom-designed audio chain featuring an amplifier, a cable, and earphones. Its eye-watering price shocked everybody because some assumed it was a pair of earphones, until they realized it’s a whole system that can’t be separated to use with another amp or cable, requiring you to add just a source to drive it. And if you think about how much money high-end audiophiles spend on flagship IEMs, upgrade cables, and portable sources and amps to complete and optimize the audio chain, Fu’s price tag was not that shocking.

So, what would be the next step to go from there? Last year (2025), which marked their 10th anniversary, Brise Audio went back to the amp design, starting with the basic structure of the Tsu amp, where every block was redesigned, then adding their latest pure-silver Shirogane wire conductors with a large cross-sectional area of Orochi, and implementing amp circuit design technology from Fugaku, to give birth to the WATATSUMI (Wata) amp. It almost felt like Brise Audio wanted to give us a taste of Fugaku’s amp, to use with other IEMs. Since you can already get a wide variety of their cables with universal connectors, what else is left? The only thing that remained was the standalone IEM itself. At the end of last year, while promoting some of their cables, a familiar Fugaku IEM shell appeared with a ‘regular’ cable and no other info, sparking a hype. This clever marketing caught many audiophiles’ attention, whetting their appetites for what was to come: Brise Audio’s upcoming flagship IEM, IBUKI, with a detachable cable and universal connectors.

Today, I’m revisiting my BEP-001 review, incorporating all relevant updates to cover final tuning, shell design, and source and cable pair-ups. I would also like to emphasize that the IBUKI tuning by Brise Audio was done using the Wata amp, an optional addition that I consider essential to hear these IEM at their full potential. But there are many other sources to consider, as well as other cables and different eartips, all of which I will cover in this review. So, without further ado, let’s find out more about the final production version of IBUKI.

Unboxing/Accessories.

While the final packaging for IBUKI hasn’t reached me yet, so I can’t fully cover the unboxing experience until a bit later, I can talk more about the included accessories now. Unlike in my BEP-001 review, this time, IBUKI came with an official premium leather case. It is not exactly pocket-friendly, but it is definitely transportable, square, and about 6.5” x 6.5”. Under the cover, there is a plastic insert with a form-fitting, secure setting for its unique shell design and cable management, which wraps around the spool formed on the insert’s exterior. I’m sure you can find a smaller case and try to store it more traditionally. But if you want a more secure way to transport these, I would use the included case.

Also included were Azla Sedna Earfit Max eartips with a silicone mesh filter inside the core, provided in a plastic storage case, in all 6 sizes. These eartips will be included with IBUKI as part of the official accessories. Eartips selection is very subjective, and I will cover other options I tried during my testing. Here, the eartips selection with IBUKI is also VERY critical, especially for treble response. Also worth mentioning, both the leather case and the eartips box were inside velour drawstring bags, which were among the included stock accessories. Plus, the Brise Audio website mentions the Ultra Suede cable organizer clip.

Last but not least is the included Brise Audio premium custom cable. Referred to as BSEP for IBUKI, which uses 4 conductors and is based on AKAGANE-35 high-purity copper wire with a quad-spiral structure, its tuning was exclusively made for IBUKI. Another exclusive detail of the design was the hardware: newly designed Grade-64 titanium parts for the Y-Split with a printed “IBUKI” name, a chin-slider with the Brise Audio company logo, and IEMs connector housings with a color-coded ring (red for the right side), all matching the IBUKI shell color. The straight 4.4mm BAL plug is Brise Audio’s original special copper alloy design, and its housing has their signature DIY-ish branded heat-shrink. As previously mentioned, the BEP-001 prototype used an mmcx connector. The final version comes with the OFC Pentaconn Ear from Nippon Dics, which is more robust and higher-quality than mmcx. Overall, I found the cable to be relatively lightweight, very supple and comfortable to wear, and non-microphonic.

Design.

Despite a strong resemblance in their exterior appearance, suggesting a similar design, Fu and IBUKI IEMs are not identical. So, let’s first revisit the Fu, which has an 8-driver tribrid design with 2DDs, 5BAs, and MEMS drivers. Their multichannel active crossover and power amplification were done inside the external compact amp module, where BA and MEMS are driven single-ended, while DDs are driven balanced. The L/R earpieces were attached separately to the amp module via 7-pin connectors. Fu’s pure silver 16-conductor soft cable is serviceable, though not easy to disconnect from earpieces. You can use any eartips with it; it’s not proprietary, and I found the sound isolation to be pretty good. These PVD black-coated pure titanium housing earpieces don’t look like your traditional IEM shells; they’re very compact because they only house drivers inside, with no crossover, filters, or sockets, and they have adjustable ear hooks to make sure they stay secure in your ears under the weight of the cable.

The IBUKI no longer relies on an external amplifier with an active crossover. Here, high-precision, temperature-stable thin-film resistor attenuators are used to adjust sound pressure levels across each frequency band, including an internal (to the shell) passive crossover circuit featuring optimized filters. Also, Brise Audio used pure-silver litz wire and audiophile-grade solder for the drivers’ internal wiring. The design was updated to a 9-driver 5-way partitioning with:

• Low: 2x 8mm LCP DD
• Low-Mid: 1x Sonion BA
• Mid-High: 4 x Knowles BA
• Ultra-High: 2x EST

The biggest change under the hood was replacing the MEMS driver with two ESTs. Then, two liquid crystal polymer (LCP) diaphragm dynamic drivers are mounted in an opposing configuration within a gold-plated OFC ring chamber with carefully selected damping properties. It’s not the same as the isobaric 2DD config; it’s their own design. Brise Audio refers to its 2DD config as Ver 2, mentioning it as an updated version over the one featured in Fu. Every BA driver was also carefully selected and optimized for each frequency band.

With all these changes, I was quite surprised that the shells’ design is similar to Fu’s. They even used the same acoustic tuning technology, with 3D-printed parts designed during Fugaku’s development, and utilized sound-absorbing and vibration-damping material treatments to improve internal and external isolation. There was also mention of using Carbon Nanotube materials on the internal driver surface and wiring, which I’m not sure if was implemented in Fu IEMs.

As already mentioned, the IBUKI shell design is nearly identical to that of Fu IEMs, including the same over-the-ear adjustable angle soft resin ear-hanger structure and the wire attachment at the bottom. But while the Fu cable was “permanently” attached, the IBUKI cable is detachable, using P-ear connectors. At the same time, it can create a bit of a challenge when dealing with aftermarket cables that typically come with a pre-shaped heat-shrink earhook and the expectation that the cable will be attached at the top of the shell. I experimented with different ways of wearing aftermarket cables, and while not everybody might approve of the look, it’s not a showstopper. With P-ear able to rotate within the connector, you can guide it over the ear or under it, to the back of your neck. I even tried it with glasses and found no issues with the earhook. The shells are very comfortable to wear, regardless of your ear anatomy. And, with the proper selection of eartips, you get great sound isolation.

Furthermore, while the BEP-001 prototype used the same pure Titanium shells as Fugaku IEMs, the final version of the IBUKI uses Ti-6Al-4V, also known as Grade 5 alloy, containing 6% Aluminum and 4% Vanadium, providing significantly higher strength, superior fatigue resistance, and greater rigidity than regular commercially pure Titanium. Plus, a PVD coating was applied to the surface for scratch protection and a finer feel to the touch.
One very important detail of the shell design I would like to mention is the golden notches on the faceplate. Fu had 3 of them, signifying the union of 3 components: IEMs, cable, and amplifier. The IBUKI has 2 golden notches that refer to 2 main components of the design: IEMs and the cable.