Fit and Comfort

Seen above is the FiiO FT5 placed on a mannequin head, to help show how these headphones would look on the human head. Note that the head is slightly under average sized, so account for the discrepancies accordingly. As with all headphones, getting a good fit and seal is crucial, so make sure to properly use the available height adjustability of the headband and the swivel/rotation of the ear cups themselves. This section is mostly a summary of the points expanded upon in more detail on the previous page and I will mention here that the FT5 is about average in terms of weight of planar magnetic headphones (heavier than average compared to dynamic driver headphones) at ~456 g, but thankfully it does wear this mass better than you would expect despite the svelte design. A lot of this is to do with the construction that allows for good weight distribution with the metal parts used throughout, and the wide self-adjusting suspension band also helps spread out the mass more along the top of your head. There are caveats associated with this for those with larger heads though, as pointed out on the previous page. The ear cups also come spring-loaded so this can be good or bad depending on how much clamp you feel on the side of your head. Lastly, the ear pads are not the largest out there but the improvements done compared to the previous FiiO headphones make a big difference in comfort and achieving a secure fit and seal this time round. The oval-shaped opening, the larger space inside, and the contouring all help. The end result is my average sized head and ears had no issues with the FT5 although I did find myself fiddling around with the top of the ear cups after ~45 min of use every so often. We get two types of ear pads and the stock suede pads were my preference for comfort whereas the protein leather pads are the way to go if you prioritize getting a good seal. I also appreciated the pad install mechanism as well as the foam gasket to prevent any sound leakage between the ear pads and the ear cups themselves, and both sets of pads were also malleable enough to fit over my ears without leaving a gap anywhere. Lastly, keep in mind that the FiiO FT5 is an open-back set and thus will be best used in a quiet environment without others in the vicinity.

Audio Performance

Audio Hardware

Please read the relevant section on this page for a brief introduction on how planar magnetic drivers work if you are unfamiliar with them. Fiio's entry to the over-ear planar magnetic headphones route is not necessarily re-inventing the wheel as much as aiming to put out a well optimized version of said wheel. The driver is 90 mm in size and uses a 6 µm thick polyarylate (PAR) diaphragm based on rigorous internal testing including long-term reliability and acoustic performance. The conductive traces are made of aluminium (weight savings) and silver (increased conductivity) and are applied uniformly using a nanoscale coating process borrowed from the semiconductor industry, with the goal being to have thick and uniformly coated diaphragms which could respond evenly to the magnetic flux generated by 20 magnets used per side. These neodymium magnets are placed 11 on the inside and nine outside in a staggered manner such that the traces, and thus also the entire diaphragm, moves back and forth rapidly and uniformly to put out a low distortion, high impact sound—provided everything works as intended anyway. The end result is a set of headphones that's about average when it comes to driving requirements for planar magnetic sets with a rated impedance of 36 Ω and sensitivity of 110 dB/Vrms (~96dB/mW here). Some powerful tiny DAC/amps such as the FiiO KA13 and Cayin RU7 will do the job well enough, let alone more powerful portable sources such as the FiiO Q7 and some higher end DAPs, although I expect most people to use the FiiO FT5 in their home/office with a desktop setup that has plenty of juice. I generally paired it with solid state amplifiers and a good delta-sigma DAC at home.

Frequency Response Measurement and Listening

I will mention that I have a general preference for a warm-neutral signature emphasizing a slightly elevated bass and smooth treble range with detailed mids and good tonal separation. I also generally prefer instrumental music over vocals, with favored genres including jazz and classical music.


Our current headphones test setup uses a set of two custom in-ear microphones for the two channels. These microphones closely adhere to the IEC711 class, but have been tweaked to be more reliable in the >10 kHz frequency range, the precise issue with my previous setup, that is otherwise still very good and will continue to be used for IEMs and earphones. Two soft silicone pinnae are installed on the sides, separated by a distance matching my head, and multiple "height" adapters have been 3D-printed for further customization, based on fit, head size and shape. Each set of microphones has an XLR output I separately adapted to 3.5 mm. I used a transparent source—the FiiO K7 desktop DAC/amp with the balanced cable connection—for measurements after confirming it was not a bottleneck in any way. This artificial head simulator feeds the microphone lines into a reference USB sound card, which in turn goes to a laptop that has ARTA and REW running. I begin with an impulse measurement to test for signal fidelity, FFT to test for headphone seal, calibrate the sound card and channel output, account for floor noise, and finally test the frequency response of each channel separately. Octave smoothing is at the 1/12th setting, netting a good balance of detail and signal to noise ratio. The default tuning was used for testing, and no app or program-based EQ settings were chosen, unless specifically mentioned. Each sample of interest is measured at least thrice with separate mounts to account for any fit issues, and an average is taken of the individual measurements for statistical accuracy.


The Harman 2018 over-ear target in particular is a reference curve many headphone makers aim for now, but I find it too bass-boosted. As such, I am opting for the Harman 2018 curve with the bass target from the Harman 2013 curve, which is what is being referred to as the "Harman Combined" target there. Before we get talking about the sound signature of the FiiO FT5, I want to first talk about the channel balance achieved here. You will notice how the left and right channels are pretty much identical all the way from 20 Hz to 20 kHz, which is the region of interest for human hearing even if FiiO mentions a 7 Hz to 40 kHz response. Indeed, knowing this was a randomly picked retail unit makes it all the more impressive given companies have difficulties getting this level of channel matching even with much more expensive headphones! There was no channel imbalance perceived thus and I will also mention that using the headphones for ~50 hours didn't change anything either for those who would undoubtedly be curious about burn-in. So far so good!


We've seen how the FiiO FT5 comes with two different sets of ear pads in the form of the pre-installed suede pads and the partially fenestrated protein leather pads in the box. Seen above are the average frequency response measurements for my sample of these headphones with both sets of pads and I will say right away that the two sound more different than the graphs might make it seem. In fact, if you were to go purely by the measurements, it would be easy to claim the sound signature is identical all the way with perhaps the faux leather pads having a bit more sub-bass. There's not much in music <50 Hz to make that dip with these pads really relevant. In practice, I found the bass with the protein leather pads to be snappier with faster transients whereas the suede pads were more diffused. The latter is more comfortable and can make for a wider sense of stage but personally I'd go with the pleather pads since it presents the FT5's strengths clearer. It does have the potential to also showcase the relative tonal imbalance too making it less of an all-rounder set so I do see why FiiO decided to go with the suede pads by default.

The FT5 clearly has a warm tonality which reminded me of the far more expensive Meze Elite. Bass and lower mids are pronounced and helps make this a more exciting set for someone new to planars but wanting something other than the neutral-neutral/bright sets that are more prevalent in the market. I also see similarities to the FT3 which had deliberate dampening to make for a bass shelf and a bassy, warm sound out of a dynamic driver set. Perhaps FiiO is aiming for different takes on this sound signature across its IEM and headphones lineup? There is a dip in the sub-bass you will notice, with electronic music coming off milder than fans of the associated genres would probably appreciate. This means the FT5 is better seen as a mid-bass beast where you have a very nice balance of resolution and impact coupled with the planar speed that you need to hear to understand better. This isn't a neutral set out of the box and not necessarily the most accurate sounding one either given some trailing ends of tones feel missing at times, as will some instrument harmonics. Instead, it's better to see the FT5 as a fun set that prioritizes vocals and brass instruments in addition to kick drums.

Note that dip in the upper mids beginning from 1 kHz? It's made all the more prominent as a result of the warmer presentation before but this is a psychoacoustics "feature" that has been widely acknowledged as enhancing the soundstage from headphones. The net result is you feel sound coming from outside your head as opposed to just inside of it. Brands such as HIFIMAN have become synonymous with this upper mids dip and I will also say that the ear gain region thereafter is not as recessed as these measurements make it seem. In fact, female vocals mostly sound fine even if some can feel in the background. Everything thereafter is mostly neutral creeping on energetic but I would not say the FT5 is a bright or sibilant set at all, let alone fatiguing. Timbre and imaging aren't strong points here though and the tonal balance does affect how jazz and orchestral music is rendered. I'd favor the FT5 more for rock and metal music than for pop and acoustic jazz. Piano-centric classic music works here as do string quartets too.


FiiO originally planned to release the FT5 earlier last year and for slightly less than what it eventually came out for. This makes for an interesting comparison wherein there are many popular releases which cost slightly less or more with few that compete directly at the exact price point. One such contender, however, is the extremely successful HIFIMAN Edition XS which has become the brand's most sold set of headphones ever—even more than the less expensive Sundara. Going through my review can help shed more light on why. This is the least expensive of the oval-shaped ear cup headphones from HIFIMAN that also provides an excellent example of the neutral-bright planar magnetic sound signature I mentioned above. It's not going to compete favorably against the FiiO FT5 when it comes to build quality and accessories though, although comfort can be a tie depending on how you find either set. The Edition XS is more likely to be an all-rounder, especially if you EQ, although the FT5 would be the set I'd recommend for someone used to a V-shaped sound from a mainstream pair of headphones and wanting to try something similar but perhaps better sounding.

The MOONDROP VENUS costs similar to the FT5 and Edition XS when it goes on sale from its otherwise higher MSRP of $600. You get a much improved build quality from the Edition XS and very similar sound, although it is significantly heavier and arguably now suffers from the newer MOONDROP PARA offering a very similar experience for half the price. Most of what I said above holds true here too and I would probably take FiiO over MOONDROP when it comes to a blind purchase in general. But the PARA is worth the gamble to where, given it costs less than the FT5 too, I would be really tempted to get it over the FiiO offering and add a decent set of dynamic driver headphones to make for a compelling two-set collection for not that much more than what the FT5 costs. One benefit the FT5 has over the other three planars is it is much easier to drive off even a portable DAC/amp though.

If you do decide that planar magnetic sets are just not your cup of tea, there is no shortage of good dynamic driver headphones. Those in the USA benefit from the likes of the Drop x Sennheiser HD 6XX available for under $200 on sale although most others will find the equivalent HD 650 costing about the same as the FiiO FT5. There's also the newer HD 660S2 which has received a recent price cut and provides slightly more bass even if there's still a pronounced drop in the lower frequencies and it, as with the likes of the HD 600/650, are best known for its accurate mids and excellent timbre. You have new contenders from China now as well with Sivga being one of the major players when it comes to dynamic driver headphones. The Sivga SV023, for example, is another case of a set of headphones which looks and feels more expensive than it is. The unboxing experience is very similar too, albeit FiiO still wins with the excellent cable and extra set of pads, and I do have a soft spot for wooden ear cups. Sivga also likes to go the warm tuning route with deliberately dampened drivers and the SV023 is a good take on this. Note how much more pronounced the FT5 is for the mid-bass and lower mids though, so the SV023 might be a safer take. At the same time, I found the FT5 to be more engaging and there's nothing wrong with being a set which plays some specific music libraries and genres very well over being a jack of all trades. This can be more of a wash since the FT5 executes its tonality better whereas most dynamic driver sets in this price range are stronger elsewhere.