Fiio FH9 review : Very capable with Minor hiccups

Sound Quality:

This flagship from Fiio is truly loaded. It uses a 13.6mm beryllium coated DLC diaphragm dynamic driver for the lows and 6 Knowles BA drivers for the rest of the spectrum. Out of these mids are handled by 4 custom made 62305 drivers and two 31736 driver are responsible for the treble.   

I have been working on some $1000+ lately, the UM Mext and 64audio Duo are excellent. While the FH9 was on the way, I had not read much about it. I was fairly unaware of its output but expected it to be better than FD5 for sure and yes, was aware that FH9 has a V shaped output.

I have to admit, I was pleasantly surprised how good the FH9 sounded out of the box. And guess what, doesn’t matter what filters you use, FH9 always retains the V shaped signature. This sound assessment is made with the black balanced filter. I will do the breakdown first and the effect of the other filters later.

I am using 4.4mm plug with stock silicone tips and Shanling UA5 and Fiio K3 for this review.


This 13.6mm BE coated DLC diaphragm DD has to be one of the most exciting part of this IEM. Even when the IEM has a semi open back design, it manages to deliver fuller and rumbly notes. Fiio says it’s their S.Turbo acoustic technology, which uses a tube to deliver powerful yet mud and bloat free lower end.

Doesn’t matter what tech is used, all it should do is sound good and the FH9 manages to impress. The impact area is not big though.. It has very good sub-bass presence, there is enough rumble. Mid bass has very good volume and punch, it moves good amount of air too. Upper bass is well controlled and stays clear of the lower mids. FH9’s technical capabilities can be felt here too. The way it manages to separate different instruments and notes while presenting them in layers is impressive. This kind of ability is usually not found with hybrid IEMs priced under $1000. It still is not the best, notes has bit of slow footed feeling even when FH9 manages to strike a very good balance of being full bodied and controlled. This DD has very good texture too and if you enjoy a textured and detail filled lower end FH9 is one of the best at this price.

Mid range:

All the 4 custom made BA drivers (I do feel these are compound drivers) do a very good job of delivering some of the highest amount of details and clarity under $1000. FH9 easily scales up to the UM Mext and even manages to shadow it with its superior micro detail retrieval capabilities. So does it take the crown for hybrid IEMs? It definitely can unless you are bothered by the slightly unnatural timber. FH9 has a metallic feel to it, especially with vocals. Both male and female vocals have good accuracy and precision but the tonality and timber are affected by a metallic feeling. Another thing that could have been better is height of vocal notes, notes have nice and wide bases but the body gets thin rapidly as it progresses while the finishing region is wider. This extra bit of area in the finishing region gives FH9’s vocals excellent resolution and definition, all this renders an unnatural timber and tonality (The body needs a bit more volume). Unaffected are the texture, both male and female vocals have plenty of texture to enjoy.

Just like the vocals instruments too have excellent details with slightly higher transparency resulting into taller instrumental notes. And again, the notes suffer from the mid body compression. It might feel like I am highlighting this a bit too much but this is the only thing holding back the FH9 from being simply the force to reckon with. All the instruments are a bit more energetic than the vocals, they have slightly aggressive stance but still then the upper mids are clear of any sibilance, unless you are a bit too sensitive.


FH9’s dual BA drivers do a really good job of exhibiting Fiio’s tuning capabilities. This treble region is not looking for anything but details. It is sparkly and has plenty of energy. The energy gained at the upper mids are carried over and maintained till the end (If you feel this energy is slightly over limit for you, use Foam tips). Notes are precise and accurate with plenty of details. Yes, the notes still have a bit of lean feeling to them but that’s perfectly fine for treble notes.

What impressed me is the cleaner feeling. Notes are uncompromised, especially with space and height, FH9 controls the notes with excellent composure and there is no high pitched spike or lack of energy with this IEM. Treble extension is as good as it gets. In fact FH9 has better upper treble energy than the UM Mext and has a more complete treble region. Layering and separation are simply in a different level for a hybrid IEM. FH9 has an enviable treble region. It nearly blows everything away, if there wasn’t the Shanling ME700 lite, this would have been the best hybrid IEM to get around $600.


FH9 has a well developed stage. Unlike the FD5, FH9 has no unnatural compression. Yes, the density of instruments is not as even as BA based IEMs like Holocene or Shozy Elsa but is plenty good for a hybrid. The Lower and mid ranges do not have the stage filling feeling because of shorter note’s height while the treble notes fill up the stage with ease. Bass and mid range notes are mostly placed inside head while the treble notes are projected out of the head. Another good thing is the stage’s dynamic expansion feeling, it does not kill or suppress the sonics and can expand a bit depending on the tracks demand. Imaging of the FH9 is fairly accurate, I wish the bass and vocals were a bit more accurate ( I love the pin pointed imaging of IEMs like Holocene and SA6 in this price) but they still are above average.

Stage size is not huge here though. The Shanling ME700 lite has taller stage and similar width. FH9 has good width and depth and the height gradually increases as the treble notes move further from the head.

There are a couple of things to keep in mind, thanks to already elevated bass and treble regions, I didn’t bother trying the bass or treble filters but had to give them a go before the review and here are my thoughts on them:

Bass Filter (Red): I understand that the bass filter must have some lower end power over the balanced/neutral filter but the bass filter is not exactly good unless you like wooly and boomy bass which lacks proper control. I was expecting more volume or impact area but there is nothing like that. Yes, thanks to slower decay, notes have gained a bit more weight. Mid range remains similar, similar vocals and details but the treble is much more controlled. After using the balanced filter for 99% of the time for this review, this bass filter sounds a lot more tamed and feels like it’s lacking the much needed bite and traction. It’s good for those who don’t want much treble energy. But guess what.. The upper mids are exactly same, energetic and agile.

Treble Filter (Green): I actually like this more than the Bass filter and guess what.. This filter has similar bass body and impact area but the weight of the notes are reduced, it still has the similar rumble, textured and layered feeling but the decay is faster. Vocals and the whole mid range has gained some energy and are a bit sharper. Upper treble is more or less similar but notes have a bit more definition. Treble region has the biggest gain here. Notes are taller and have a lot of energy, still then, it doesn’t get uncomfortable.  It sounds a bit more vivid and raw-ish. Yes, this thing definitely pushes the mids a bit deeper into the V.



VS Shanling ME 700 lite:


FH9 is easily the best hybrid IEM from Fiio. Is it the best Hybrid IEM around $600? If not the best, it is one of the best for sure. If you want details, especially treble resolution and definition, FH9 can top your list. It doesn’t have basic tuning flaws and everyone can enjoy this IEM thanks to the tuning nozzles. The only thing one can complain about is the slightly metallic timber, this too can be cured to some extend with a good quality copper cable. Yes, the stage is a downer especially when this is a semi open IEM, we all were expecting more here but there will be hardly any complains about it.

FH9 is a very capable IEM held back by a couple of oversee-able hiccups. There might not be one but it will be awesome of Fiio will be iron out these down sides with FH9S maybe.. Fingers crossed.

Wishing you guys the best. Enjoy your music!! Cheers!!



Suman Sourav Meher

Suman Sourav Meher

My humble audiophile journey started in 2010, when I was in college, where I fell in love with the elements, nuances, and variations of this mesmerizing world. The ability of tiny earphones to recreate amazing sounds made my bad days tolerable and good days better! Now I am a full-time audiophile with a preference for musical tracks, especially vocals and engaging ones. I must admit I am addicted, but not to drugs or alcohol, but to earphones. Come join me as I share my experiences, bad or good, and let’s have some fun!


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