The FiiO FH5s is a quad driver IEM with 2 balanced armatures and 2 dynamic drivers. This $259 earphone has a triple-switch tuning system and semi-open back design.

FiiO official website: https://www.fiio.com/

Disclaimer: This sample was provided for the purpose of an honest review. All observations and opinions here are my own based on my experience with the product.

FiiO FH5s

Specifications

• Impedance: 40Ω（@1kHz)
• Frequency response: 10Hz – 40kHz
• Sensitivity: 106dB/mW
• Headphone plug: 2.5/3.5/4.4mm gold-plated plug

Packaging & Accessories

The FH5s box looks and feels really premium, even for something in this price range. On the front of the box is an image of the shell plus an exploded diagram showing the internal structure and components. On the back is a diagram showing the effects of the tuning switches. Here’s a list of everything in the box:

• FiiO FH5s IEMs
• Detachable silver-plated copper cable
• Detachable 2.5mm, 3.5mm and 4.4mm plugs
• 8 pairs of single flange silicone eartips in 3 styles (bass, vocal, balanced)
• Carrying case
• 1 pair of double-flange silicone eartips
• 3 pairs of foam eartips
• MMCX tool (for detaching cable)
• Cleaning brush/switch tool
• Documentation/warranty

Design

Without a doubt, the most striking feature of the FH5s’ shells is the “dragon scales” vents on the faceplates. Beneath the vents, you can clearly see the open-air mesh guides that give FH5s its semi-open back nature. The aluminium-magnesium alloy shells are CNC-machined to perfection and have a smooth matte finish.

Another feature of this IEM is the 3 tuning switches that are located on the top of the shells. These can create up to 8 different profiles allowing you to customize the sound to suit your own preferences. The MMCX connectors have blue and red markings to easily distinguish the left and right sides respectively.

Internally, the FH5s houses a 12mm beryllium-plated diaphragm/PU gasket + 6mm Beryllium-plated + Knowles TWFK-30017 compound BA. The 4 drivers have been tuned in conjunction with the TRISHELL acoustic design to reduce resonance and distortion.

Weighing in at 8.8g for each side, the FH5s shells are lightweight but extremely robust and durable. They adopt FiiO’s third-gen ergonomic design for maximum comfort. I guess they got it right because I can comfortably wear these all day long.

Due to its semi-open nature, the FH5s has below-average noise isolation but it’s still sufficient for using on the go and in noisy environments.

Cable

The included cable is a 4-core silver-plated copper (SPC) type. It has transparent and colour-coded plastic MMCX connector housings and flexible heat-shrink ear hooks. The chin slider, Y-split and straight plug are all matching polished aluminium. Speaking of the plug, you can easily switch between the 3 included terminations and the mechanism feels sturdy and secure.

In terms of handling, the cable performs extremely well. It’s supple, devoid of any kinks or memory and has minimal microphonics.

Sound

Let’s talk about those switches

So, the FH5s is another IEM with tuning switches and by adjusting them you can slightly alter the frequency response. By far, the switch that makes the biggest change is the bass switch. The others make some very minor changes which you can see in the images below.

My personal preference for the switch settings is (unsurprisingly?) with the bass switch turned ON. Contrary to what you might be thinking, it’s not because I want more bass than the Standard setting provides. Rather, enabling the bass switch creates what is to my ears a more pleasing tonal balance. It effectively just takes some of the edge off the treble that (spoiler alert) can be a little aggressive.

Gear used for testing includes:

• PC -> Topping DX7 Pro
• Soundaware M2Pro
• iPhone with Earmen Sparrow

The FH5s is fairly easy to drive but because it is a particularly resolving IEM it scales well with better sources. I would call the sound signature neutral/bright. The sound is highly detailed and crisp but for me is suited better to low volume listening as the upper mids/treble glare increases and you turn things up.

Bass

The bass is my favourite aspect of the FH5s’ sound. It’s tight, fast and deliciously textured. There’s no unruly resonance or cloying decay, thanks to the Beryllium-coated driver, the strength of the chassis and semi-open design. I chose to leave the bass switch turned ON, but the bass is ample and engaging even with the switch in the OFF position.

The bass has a great balance of force, punch and impact. You can hear every vibration of the strings on the bass guitar in Miles Davis’ “Portia” (starting at 1:55) with great detail. The separation of the bass from the trumpet and keyboard makes it truly vivid and engaging.

When listening to Daft Punk’s “Give Life Back To Music”, the FH5s renders the kick drum with a tidy slam and visceral, satisfying impact without covering the guitars and vocals in the midrange.

Mids

The FH5s presents the midrange with excellent clarity and an open, spacious feeling. Notes are neutral in size and forwardness with a sprinkle of brightness in the upper midrange. The spike in the treble gives the upper mids a slight edge resulting in a tone that’s not completely natural but is very clear.

It’s a midrange that’s bursting with energy and sparkle, one that will certainly get your attention. However, the occasional upper registers of a piano or female vocal belts could use a touch more warmth, particularly at higher volumes. One example is K. Michelle’s “Hard To Do” which sounds beautifully clean on the FH5s but there is a hint of graininess in the vocals.

Treble

FH5s’ top end is slightly lifted which makes it airy, precise and detailed. But there’s a bite to it which comes mainly from its 8kHz peak. Trebleheads will surely love the crispness of the highs but those who are treble-sensitive might have a hard time regardless of the switch settings.

Treble notes are slightly thin and could use a touch more body. This quickly becomes apparent as you turn the volume up and the high frequencies seem to leap forward and upset the tonal balance. This does result in fantastic detail retrieval, even if it comes at the cost of lower overall resolution.

Soundstage

As one would expect from an open-back design, the FH5s has a spacious and airy soundstage. It has more width than depth, creating an elliptical space that stretches wide to the sides and moderately in front. The large stage aids in instrument separation but the forwardness of the treble limits the FH5s’ layering. As a result, stereo imaging is good but not quite 3-dimensional or holographic.

Comparisons

DUNU DK-2001 (299 USD)

The DUNU DK-2001 is a hybrid quad-driver IEM with a 1DD+3BA configuration. It has a similar sound signature as the FH5s but has a slightly warmer overall tonality. The DK-2001 has slightly more bass quantity and more fullness in the upper bass.

That bass fullness carries over into the lower midrange and gives the DUNU a slightly warmer midrange as well as more body to vocals and instruments. Male vocals are more forward and sound more natural compared to the FH5s which renders them with a slight dryness albeit with better articulation.

In the treble region, the DK-2001 has rounder and slightly softer notes but maintains a similar level of energy. The FH5s, on the other hand, gives a harder edge to treble notes but at the same time creates a wider and more spacious soundstage.

FiiO FH3 (129 USD)

The FiiO FH3 is a triple-driver hybrid with a 1DD+2BA driver configuration. Starting with the bass, the FH3 has more quantity and overall impact but lacks the speed and finesse of the FH5s. Where the FH3 bass displays some mild bleeding into the midrange, the FH5s keeps any resonance under tight, unwavering control.

There’s a noticeable drop in midrange resolution on the FH3 on most tracks. However, when there’s a cacophony of crash cymbals and shrieking electric guitars, the FH5s’ lead in this area diminishes. For the most part, however, the FH3 can’t match the transient speed and cleanliness of its bigger sibling.

In the midrange, instruments and vocals have more body and forwardness on the FH3. In comparison, the FH5s sounds cleaner and more organized. Vocals are warmer and richer on the FH3 whereas they’re clearer and more detailed on the FH5s.

The FH3 has less upper midrange and treble presence and thus can’t match the level of detail retrieval that the FH5s achieves. Furthermore, FH3’s additional warmth and body means it has a more intimate soundstage.

Conclusion

The FiiO FH5s is a testament to the value that FiiO consistently delivers with its products. The build quality of its over-engineered dragon scales shells, the high-quality modular cable and the overall number of accessories is already more than we’re used to seeing at this price point.

Furthermore, it has a highly detailed, spacious and customizable sound. But just like a dragon, the FH5s can occasionally bite and breathe fire so it won’t suit everyone. Nevertheless, if you’re someone who likes some treble energy or you’re not averse to using EQ, the FH5s is definitely a worthy proposition.