Final Audio Design FI-BA-SS


Reviewer at audio123
Pros: Organic & Resolving, Top Clarity, Massive Extension
Cons: Cable
The Final Audio Design FI-BA-SS is the flagship model of the Heaven Series. Like other iems in the Heaven Series, it utilises a single balanced armature driver. On the website, it states “Our Flagship BA-SS takes balanced armature earphones to another level of performance”. With only a single balanced armature driver, it is hard to imagine the level of sonic performance that the FI-BA-SS can produce.
“With our special “BAM Mechanism” design, air movement inside the housing is optimized, allowing the BA-SS to produce deep bass without the distortion and muddiness normally reproduced by BA unit earphones. The design theory of this breakthrough earphone rests on a single driver directly connected to the circuit – uncomplicated by the presence of other drivers. The BA-SS is a handmade product, made by Japanese sound engineers with a full-focus on ideal sound with no compromises. This is our flagship model of the BA series and our premium model in the Balanced Armature category.”
Final Audio Design has incorporated Balanced Air Movement (BAM) technology in the FI-BA-SS. This allows the sound to be projected out from the single balanced armature driver effortlessly. The main purpose of utilising a single balanced armature driver is to control all the frequencies and ensure coherency at its best. The presentation will be clear cut and straightforward to the listeners. The combination of technicality and musicality has reached a pinnacle in the case of the FI-BA-SS.

Housing: Stainless steel
Driver Unit: Balanced Armature Driver
S.P.L: 112 dB
Impedance: 16 ohm
Length of Cable: 1.4 m
Weight: 20 g

Build Quality
The build quality on the shell of the iem is fantastic. The cable is decent but more is expected given the price tag of it.


The FI-BA-SS has a special sound that no IEMs can replicate. It is hard to describe the sound of the FI-BA-SS. The sound has multiple characteristics to it. Organic, Resolving, Technical and more. Sophisticated or complicated the sound of the FI-BA-SS may be that it is difficult to reach a perfect description. Hence, a detailed explanation is needed. The FI-BA-SS offers an insane amount of extension at the opposite ends of the frequency. No words can describe the resolution and refinement of the FI-BA-SS. It is a very revealing iem that presents everything effortlessly. The FI-BA-SS is bright sounding and the mids are prominent. There are hardly any veils in the sound. Transition from other iems to FI-BA-SS makes it seems that multiple veils are being lifted. That is the sonic prowess of the FI-BA-SS. As straightforward as you can get from the sound, the FI-BA-SS excels in being “honest” in giving a raw sound to the listener. Clarity is very impressive. Details retrieval is on point. There is a decent bass to the sound coupled with the developing treble that enhances the whole listening experience.

The standout for me is the splendid midrange. The prominent mids’ purity exemplifies the raw and organic sound of the FI-BA-SS, making it one of the best iems for the vocals genre in the market at the moment. Free of colouring and distortions, the sound reproduced is just too transparent and allows the listener to be immersed in the tracks. The single driver implementation proves its sonic capability. It reveals everything effortlessly. The soundstage is very wide for an iem. Engaging presentation allows the vocals to be portrayed live to the listeners.

Lows (9/10): The bass is perfect as you can listen to every single variations. There is no slam to it but just a consistent and coherent presentation. It is certainly not the type of bass that bassheads crave. However, the accuracy and tightness of the bass is right there and is comparable to multiple balanced armature drivers iems. The lows of the FI-BA-SS is really impressive. You need to listen to the FI-BA-SS to accurately understand what the lows is all about as words can only describe it to a certain extent.

Mids (10/10): The mid range is my favourite part. Mids are straightforward and detailed. The FI-BA-SS shines on the vocals tracks. Vocals are cut through to the listener and the highly energetic sound makes females vocals sweet. Instruments sound particularly impressive. With the airiness and spaciousness, the sound is developing slowly to reach a high resolving nature. The mids are fantastic in how it presents itself. Coherent, clear, engaging, organic, addictive, resolving etc. There are far too many adjectives to describe it. It is in another league.

Highs: (9/10): The highs are very bright and this shows the extension of it. However, it can reach an extent of being sibilant. In all honesty, that is the only flaw across the whole spectrum.

The FI-BA-SS from Final Audio Design shows exactly what a single balanced armature driver can do. Coherency is one of the best I have heard from an iem. Phenomenal sound with a huge price tag. This iem is too unique an iem to pass.
Nice review! How is the isolation in the public places? :)
How does this fare in 2020?


Headphoneus Supremus
Pros: Great Sound Quality; Transparent; Detaled
Cons: Fragile non-detachable cable
The narrative of how I came upon Final Audio Design is found in my reviews of Sonorous X and the Piano Forte X. Suffice to say that I do enjoy the unique music presentation proposed by Takai-san, the man who was behind Final Audio Design. I am proud owner of the FI-BA-SS, the Heaven S, the Heaven VI, the Pianoforte VIII, IX and X, the 1601SB (predecessor to the Pianoforte series), Lab 1 and AKR02 (special edition FI-BA-SS in collaboration with AK). I also have the Hope VI and the Sonorous X.
I remember when I first started with the Heaven S, the Final Audio Design FI-BA-SS was spoken of in almost hushed tones. It was supposed to be this amazing single balanced armature from Final Audio Design with a sonic signature unlike any. The reverence was also because at that time it was the most expensive universal IEM around. To use the term of the Jaben Singapore team, it was “special”. It was proclaimed by Final Audio Design itself on its web site as being their flagship.
I was going fine and told myself I don’t need the FI-BA-SS. However, curiosity got the better of me. So, one day I walked into Jaben and declared that I wanted to try out the FI-BA-SS. The famous last words I uttered to a grinning crew at Jaben was: “I’m just trying”. Less than a month later, I was the proud, if not a little sheepish, owner of the little silver coloured bullets. Well, I am proud of myself that I did not succumb immediately but had agonized for a few weeks over the inevitable eventuality.
Technical details
The FI-BA-SS is made of shaved stainless steel. It is entirely hand made in Japan. Although it has a compact and small housing, it has a nice solid feel to it. Inside the housing there is just a single balanced armature driver. The thinking was to have just one driver obviates any need for crossover or any muddiness introduced when there are a few drivers. I imagine the idea was to have a housing that is simple and pure as is possible. All around the back of the housing are vents which allowed the air to be released. It was called Balancing Air Movement to prevent sound leakage and control air flow.
Build Quality
Build quality is impeccable. For the then highest price for a universal IEM, you get two solid nuggets of stainless steel. They are probably still the classiest housing I have seen for an IEM. With the vents at the back of the housing, it almost reminds me of a jet engine. The Final Audio Design FI-BA-SS looks simple, classy and elegant.
The non-detachable cable is quite thin, soft and has a penchant for entangling. All of which conspire to give me sleepless nights on whether I should pick up a spare FI-BA-SS in case I inadvertently kill it one day. The cable is terminated with a low profile right angled 3.5mm plug. While the housing extends its stainless steel housing to a short tube into which the cable enters,  there is no strain relief where the cable goes into this tube and it only adds credence to my nightmare scenario.
Comfort and Isolation
Because of the small footprint of the FI-BA-SS, it fits nicely into most ears. And while solid in feel there is not unduly great weight. Once you insert it into your ear canal, you hardly notice it is there. I do find that the stock ear tips are very comfortable. But of course, because it is pretty standard stuff, it is open to anyone to substitute the ear tips with any make of their own choosing for more comfort.
Insofar as isolation is concerned, this really depends on the type of ear tips that is being used. For the stock ear tips, I can say that isolation is pretty good. Despite my concerns, there does not seem to be any leakage of outside noise through the vents at the back of the housing.
Music Genres
Having a large collection of music, I have much choice in what I want to listen to. However, I will confess that with the FI-BA-SS, I tend to stick to acoustic vocals, jazz, pop and generally vocal music. I am not excited when listening to heavy metal or heavy rock with them because while it does possess quite a bass kick, the quantity of the bass is not quite optimal with these two genres.
Sound Quality
The first time I tried the FI-BA-SS I was stunned by how bright it was tonally. Once I got past the initial shock, I slowly learned to appreciate its sonic qualities.
What I will say is that the FI-BA-SS like its stable mate in the full sized can category, the Sonorous X, in that it paints a vibrant, vivid and rich presentation of the music. At the same time, there is surprisingly no harshness to its trebles even though they seem to feature prominently. The trebles are extended and pristine. There is plenty of grip and timbre in the mids. The bass is probably its Achilles heel – there is plenty of texture, resonance and quality in this department but it simply lacks the quantity that is required for certain types of music. Overall, there is also great detail in whatever music it plays. The flip side of this is that if the quality of the source is not up to scratch, do not expect the FI-BA-SS to gloss over the weaknesses.
One thing that is shocking about the FI-BA-SS is in how raw and emotional it makes the music sound. I still remember sitting in a freezing hotel room somewhere in North East China during the midst of winter and it was minus 35 Celsius outside, and I was listening to Diana Krall wrapping that voice of hers around the lyrics of Walk On By on the FI-BA-SS off my brand new AK100 – the rawness of her emotions and the nuances of her voice really tugged at my heartstrings and sent shivers down my spine.  I swear that I could feel myself tearing up. But then again, it could just be cabin fever from being snowed in…
As with the other Final Audio Design IEMs, the cables are non-detachable and so the question of cable rolling is moot.
The FI-BA-SS seems to be an equal opportunist when it comes to pairing with music sources. I have used it with the iPod Classic all the way up to the Lotoo Paw Gold and have not experienced anything adverse worth reporting.
Whatever else I can say about the sound signature or sound quality of the FI-BA-SS, what will always come first to my mind is how vivid and vibrant, & raw and emotional it is.
Thanks, James444! It was your extensive posts about the FI-BA-SS that gave me the courage to pick up what was then the most expensive universal IEM around. :)
How different is the AKR02? 


Headphoneus Supremus
Pros: My Precious!
Cons: Sneaky little hobbitses.
We wants it, we needs it. Must have the precious.
They cursed us. Murderer they called us. They cursed us, and drove us away. And we wept, Precious, we wept to be so alone. And we only wish to catch fish so juicy sweet. And we forgot the taste of bread... the sound of trees... the softness of the wind. We even forgot our own name. My Precious.
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It's a bit of a love/hate type of earphone --- those that love it, love it. Those that don't, well, they'll concede that it sounds clear, but that they weren't impressed with it at all, and that it's overpriced. Don't get it for a value proposition, obviously. It's not practical, and the casing material construction alone is expensive. Get it because it's special.
 What strange reviews these earphones elicit...
Well I just bought one. Hopefully I won't turn into a golem


Headphoneus Supremus
Pros: Irreverent, Impetuous and Cruel
Cons: Irreverent, Impetuous and Cruel
This is not a proper review, just really some rambling from the appreciation thread...

I have no idea why I didn't really like them so much the first time. I guess it is their unorthodox nature. They are a bit impetuous, however I have really been enjoying them the last couple days, prompting me to write some unorthodox impressions. Please excuse their rambling and possibly incoherent nature.

The SS is a dirty little vixen, devoid of etiquette. She can turn on a dime from prim and proper to screeching, kicking and clawing; so goes the quality of the recording, there goes the SS.

The vocalist is who she loves the most. She pulls in close and puts a loving hand on the microphone and beckons you in. Vocals are the anchor in this love affair but the dirty vixen also has a thing on the side with the drummer. The SS in particular likes his snare. I can almost feel the sticks impact and the skins stretch. On second thought, I think she’s sleeping with the entire band.

She’s a cigarette smoker and a whiskey drinker. The SS doesn’t mind slumming and she enjoys hanging with the sleaze rock crowd. In fact, the SS has taken my previous distortion guitar favorites out back, kneed them in the groin, rubbed dirt in their faces and spit on them for good measure; then walks away leaving them in the gutter.

Love/Hate guitars couldn't possibly sound any nastier. I can practically feel Bones spitting his rap in Stuck Mojo. The wall of sound Sevendust produces is rich, deep and edgy.

Oh! Darling, the SS can play the role of the hippie. George, John and Paul’s voices sound fantastic on the SS. I get a live edge and an outdoor vibe from the SS with Abbey Road. The Sheepdogs, I Don’t Know, sounds as if it was recorded on the back of a flatbed, out in a field somewhere. And now it’s on to glam and Bowie simply sounds wonderful… must-resist-eyeliner.

The SS isn’t very forgiving and she can be downright cruel at times but she’s just got a way about her that has me coming back for more.
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It's not forgiving at all, and you explained why quite nicely!
Night Crawler
Night Crawler
Nice read, shane. The SS is still the best damn IEM I've ever owned. [ :