FiiO F9 PRO & FH1 – Double Dragon

Immediately after the launch of F5, F9SE and F9 IEMs, FiiO instead of catching a breath of fresh air, decided to be seriously involved in the improvement of their own designs, thus F9 PRO and FH1 see the light of the day, I’ll write about both products in detail in the shortest time.

I. FiiO F9 PRO

As in case of F9, F9 PRO are hybrid earphones that uses a dynamic driver to deliver a good base response and two balanced armatures that takes care of the mids and treble.

Unlike the original F9, the PRO version uses balanced armatures from the renowned American manufacturer Knowles, the exact models is TWFK-30017-000.

Package contents

The same two detachable cables can be found, one is a normal 3,5mm one that offers in-line controls, the other one is a balanced 2,5mm cable of a higher quality.

This time package contains 12 pairs of ear-tips, classified in 4 different categories (each having 3 pairs of small/mid/large ear tips) as follows:

  • Black silicone ear tips – they offer the most balanced sound, nothing stands out too much, for me those are little uncomfortable and isolate not as great, negatively affecting the bass performance.
  • Black silicone ear tips with a red inner tube – these ones absorb some of the treble highlighting the low end – the perfect ear tips for bass heads.
  • Transparent silicone tips with a red inner tube – with this tips mids come forward a bit highlighting voice performance. For a relaxed and more natural sound signature this are the right tips for the job.
  • Black memory foam tips – very similar with Comply tips, they offer the best comfort and isolation helping a bit that bass response. The heat from the ear canal makes memory foam soft that easily takes its shape so this are my favorite ear tips because of the superior comfort and slightly accentuated bass.

Besides the hard-shell case that is also waterproof a mini pouch is offered as well. Made from fabric and being that small is really great at safe transporting of F9 PROs.

Sound Quality

F9 PRO compared to the original F9 uses Knowles balanced armatures that had a greater impact on sound that I initially anticipated.

Impressive is the very good tonal balance that F9 PRO is capable of – the only real downside of the F9.

Frequency response is no longer V-shaped, the mids this time around are much more present and the treble is not that bothering any more. Overall, I think they offer a reference sound at an entry level price.

Bass is reminiscent of the one from F9, on the other hand using memory foam tips really wakes up a deep and rumbling bass.

I still think bass response of F9 PRO is fast, having a good precision and extension.

On both F9 and F9 PRO I feel that bass puts more emphasis on quality rather than on quantity. It goes pretty low, but it cannot be considered as reference level due to shy sub-bass, however using the right ear-tips care completely resolve this issue.

It is executed strikingly fast with a serious impact on the eardrums, very obvious on electronic music, at higher volume I have a feeling that my entire inner ear is vibrating.

Unlike the former F9 IEMs, PROs do not sound as aggressive – a good consequence if you listen to more musical genres.

I was impressed by the mids as well that are much more present and alive, offering more emotion and soul than the F9 predecessors.

As a result, bass as well as mids almost always are coming forward offering an exact dose of musicality and acoustic performance.

The more pronounced mids have greatly reduced the feel of plasticky and false sound, sometimes heard on F9.

At last I can easily listen to vintage music where mids are really bold and outlined, and to modern music too where bass can be the most important aspect.

I enjoyed the most the performance of the highs which is much more natural and I was even wondering if it is due to new balanced armatures or due to crossover changes, because the differences are quite big.

Overall, I liked F9 but razor-sharp nature of the treble made me use F5 more often to the detrimental higher performance of F9.

The PRO version has completely solved this problem, providing not just the same level of detail and resolution in the higher registers but also making it more relaxed and natural. Brightness is no longer present and I enormously enjoy the new sound signature.

Moving from F9 to F9 PRO the immediate impression is that the sound becomes livelier and more natural, much closer to reality that seemed calmer.
Finally, the tonal balance is present and as a result almost nothing stands out, everything seems in its place.

Holography is more impressive this time around; closing my eyes I can swear that the sound emanates at 1-2 m away from me and not millimeters away from my ear-drums, the sensation is really interesting. Few IEMs can sound so airy and fast, with a good tonal balance.

The disappearance of harmonic distortion on treble (present on F9) creates a soundstage that is not only deeper and broader but also airier and clearer.

F9 PRO on the right equipment is completely another animal than F9. I’m sad that they have not been offered at the same time because I consider them a logical upgrade to F9 – especially if natural sound is what are you looking for. Very rarely I can associate a natural sound with balanced armatures, but it is possible and F9 PRO shows exactly that.

Together with F9 PRO I’ve tested a pair of FH1 on the same equipment; I’ve made a solid impression about F9 PRO so FH1 will have a fierce competitor this evening.

II. FiiO FH1

FH1 are also hybrid earphones that uses a dynamic driver for base response and just a single balanced armature (instead of two on F9 and F9 PRO) at that is Knowles 33518.

Another important change is the use of a larger diameter dynamic diaphragm, more exactly a 10 mm one instead of 9.2mm one on F9 and F9 PRO. Besides this fact, it is reinforced with a brass metal ring that increases the surface area by 25.7% – two important changes that suggest a better reproduction of the low end, will see if that is the case.

A last change that again had an impact on the sound is the use of brass in the construction of the sound tube to which ear tips are attached, and the balanced armature is placed much closer to the ear than in case of F9 and F9 PRO.

To reduce production costs in place of an aluminum body shell a high-gloss plastic one was used, I do hope this change will not have a bad impact towards sound quality.

The same hard-shell protection case can be found in the package and two detachable cables: a normal 3.5 mm one with in-line controls and a balanced 2.5mm one of a higher quality.

Again 6 pairs of ear tips can be seen, from which 3 pairs are the standard black silicon tips – most balanced sound across the board and another 3 pairs that has a red sound tube that are used for waking that bass from hibernation.

Overall the package and its accessories are very similar to the F9 one.

Now let’s get to the most interesting part.

Sound Quality

If the original F9 would represent the Yin concept, then surely FH1 will be their opposite twin brother Yang – both are opposed diametrically when it comes to acoustic performance.

But let’s get it from the start.

Bass performance is very different, it reminds me a lot about F5 performance, even by that of Sennheiser Momentum In-ear or IE-80. Bass vibrates sensibly more, it goes lower and has clearly longer decays. Fortunately, it doesn’t overflow the mid frequencies.

Not just extension is better going into sub-bass region, but it’s inner kick is stronger as well. This time around I feel like the emphasis was placed more on quantity rather than on quality.

The transient response bothers me a bit, the vibration of the notes is longer than what I am accustomed to and layers and sub-layers of bass are not present.

If I would not be so critical with its bass response, it can be considered really good.

Besides the muscular bass I have an impression that the balanced armature emphasizes mids a little bit more that the higher notes. Thereby mids are more pronounced, capturing attention to throughout the song.

Voices are becoming syrupy and warm and as a result vintage music sounds foggy masking some micro-details from the decor.

Holography has little to suffer as well, due to the less airy sound, everything sounds closer to the listener, the action takes place closer to the eardrum and that leads to a smaller soundstage both in depth and in width.

It is shocking enough to think that a hybrid earphone that uses a balanced armature can sound so warm and sweet, without a touch of artificial sound.

Although the mid frequencies are warm and pleasant, they do not always come upfront due to a less airy presentation.

The highs are completely opposed to those heard on F9, they are much calmer, more relaxed and placed deeper into the stage.

The highest notes have a slight attenuation, as if the top was cut a bit, this effect was only heard on higher quality Hi-Res material. On normal lossless music this effect is rarely heard.
Attenuation of the treble creates both the impression that notes hit an imaginary wall but also the sensation of intimacy, in which the action takes place in a more cramped and crowded place.

I think the frequency response of FH1 is opposite to that heard on F9, and the F9 PRO is exactly between the two models, with the most accurate and linear sound.


Consequently, I think that FH1 are most musical and relaxed earphones from FiiO’s portfolio, while F9 PRO have the most accurate and natural sound from all its stable.

I am glad that I can easily tune the sound using only the ear-tips found in the package, especially those in the F9 PRO package are sounding very different from each other.

F9 PRO easily rivals IEMs from established manufacturers. Just a week ago I have listened to a pair of Shure SE315 and those sounded as if I had wool in my ears, the F9 PRO easily outperformed them by a long shot.

I recommend at least trying F9 PRO, it’s worth your effort, I decided to keep them in my stable for a comparison with the next review candidates.
The FH1 is the embodiment of musicality, offering a relaxed and easy-to-listen sound for hours and hours.



  • Removable cables, package rich in accessories
  • Good extraction of details
  • Airy presentation
  • Naturalness and rich tone
  • Wide open soundstage
  • Rivals performance of more expensive earphones
  • Best comfort until now (using foam ear-tips)


  • None at this price point and performance

FiiO FH1


  • Lively and dynamic sound
  • Very obvious musicality
  • Good macro-details
  • Excellent textures of the notes
  • High level of comfort due to lack of air pressure in the ear canal
  • Excellent price for what it offers


  • Lack of linearity, coloration on bass and mids
  • Extraction of micro-details was not a priority
  • Shy top end

Associated Equipment:

FiiO F9 PRO, F9, FH1, Q5, HeadAmp Pico Power, Gilmore Lite Mk2, Matrix X-Sabre Pro, Audio-GD Master 9, iFi iPurifier2

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