FiiO X5 3rd gen Premium Hi-Res DAP

General Information

The new generation X5 was just released to the public at FiiO 2016 Winter Launch Event featuring:
Dual flagship DAC, Right/Left channel controlled by one AK4490 chip separately.
Dual Operating modes, supports instant switch between Android /Pure music mode.
Dual headphone outputs, 2.5mm TRRS plus 3.5mm TRS.
Dual Quick Charge protocols.
Dual Micro SD slots and 32GB internal storage, supports up to 544GB.
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Latest reviews

Pros: Sound quality/tonality, build quality, value, features, additional DSP options, UI, wireless options, ease of use
Cons: Some software stability issues, on/off button location, slight lag, and slow boot speed

Picture are default 1200 x 800 resolution - click (photos in tables) to view larger images.


That most elusive of audio hardware components – the perfect DAP or Digital Audio Player. Anyone who is into personal (and especially portable) audio will recognise the search for nirvana. The perfect player must be able to drive practically any headphone (from the most sensitive to the harder to drive), must sound incredible, have a perfect UI, perfect wireless, perfect bluetooth, perfect sorting ability, perfect EQ tools, long battery life, huge storage ability, be able to interface with practically any add-on we throw at it, and be priced at the value end of the spectrum. If you think I'm being just a little satirical – it's intended.

It is unlikely we'll ever agree what is the perfect DAP, so rather than trying to cover everything, I'll simply look at what “pushes my buttons” and why. On this journey, we'll explore the X5 3rd Generation (or X5iii) through my eyes (and ears), compare it to my own needs/wants, and take a little look at what FiiO offers at $400, and whether I think it is subjectively worth it. Along the way – we'll also look into some of the comments and critiques I've seen elsewhere, and my take on them (whether I think they are justified). So lets have a look at what I think of FiiO's X5iii.


By now, most Head-Fi members should know about the FiiO Electronics Company. If you don’t, here’s a very short summary.

FiiO was first founded in 2007. Their first offerings were some extremely low cost portable amplifiers – which were sometimes critiqued by some seasoned Head-Fiers as being low budget “toys”. But FiiO has spent a lot of time with the community here, and continued to listen to their potential buyers, adopt our ideas, and grow their product range. They debuted their first DAP (the X3) in 2013, and despite some early hiccups with developing the UI, have worked with their customer base to continually develop the firmware for a better user experience. The X3 was followed by the X5, X1, X7 and most of these DAPs are now into their 2nd or even 3rd generations.

They've also developed new cables, desktop and portable amplifiers, DACs, ear-buds and earphones. FiiO’s products have followed a very simple formula since 2007 – affordable, stylish, well built, functional, measuring well, and most importantly sounding good.


The X5iiiwas provided to me gratis as a review sample. I have made it clear to FiiO in the past that I did regard any product they sent me as their sole property and available for return any time at their request. I have continued to use a lot of their gear for follow up reviews, but also for everyday use. I had previously purchased a lot of FiiO products and inquired if I could purchase the X7 a while ago from FiiO. They have insisted I keep any further products for for my own use. So I acknowledge now that the X5iii I have is supplied and gifted completely free of any charge or obligation. I thank FiiO for their generosity.

I have now had the X5iii for 7 months. The retail price at time of review is ~ USD 400.

PREAMBLE - 'ABOUT ME'. (or a base-line for interpreting my thoughts and bias)

I'm a 50 year old music lover. I don't say audiophile – I just love my music. Over the last couple of years, I have slowly changed from cheaper listening set-ups to my current set-up. I vary my listening from portables (mostly now from the FiiO X5iii, X7ii and iPhone SE) to my desk-top's set-up (PC > USB > iFi iDSD). My main full sized headphones at the time of writing are the Sennheiser HD800S, Sennheiser HD600 & HD630VB, and AKG K553. Most of my portable listening is done with IEMs, and it has mainly been with my own personally owned IEMs - the Jays q-Jays, Alclair Curve2 and Adel U6. A full list of the gear I have owned (past and present is listed in my Head-Fi profile).

I have very eclectic music tastes listening to a variety from classical/opera and jazz, to grunge and general rock. I listen to a lot of blues, jazz, folk music, classic rock, indie and alternative rock. I am particularly fond of female vocals. I generally tend toward cans that are relatively neutral/balanced, but I do have a fondness for clarity, and suspect I might have slight ‘treble-head’ preferences. I am not overly treble sensitive, and in the past have really enjoyed headphones like the K701, SR325i, and of course the T1 and DT880. I have a specific sensitivity to the 2-3 kHz frequency area (most humans do) but my sensitivity is particularly strong, and I tend to like a relatively flat mid-range with slight elevation in the upper-mids around this area.

I have extensively tested myself (ABX) and I find aac256 or higher to be completely transparent. I do use exclusively red-book 16/44.1 if space is not an issue. All of my music is legally purchased (mostly CD – the rest FLAC purchased on-line). I tend to be skeptical about audiophile ‘claims’, don’t generally believe in burn-in, have never heard a difference with different cables (unless it was volume or impedance related), and would rather test myself blind on perceived differences. I am not a ‘golden eared listener’. I suffer from mild tinnitus, and at 50, my hearing is less than perfect (it only extends to around 14 kHz nowadays). My usual listening level is around 65-75 dB.

For the purposes of this review - I've used the X5iii and tested most of the functions I am able to. This does not include some applications like DLNA or DOP output – which I can neither test properly, nor am I interested in. We'll touch very briefly on streaming, but again it won't be an area I'll spend a lot of time on, simply because I simply use the X5ii predominantly as a player. I have prior experience with entry level Sony's (very early models), then step-ups to the Cowon iAudio7, iPhone4, iPod Touch G4, iPhone 5S, HSA Studio V3, FiiO X5, X1, X3ii, X5ii, X7, X1ii, X7ii, X3iii, iPhone SE, Cayin i5, and the L&P LP5, L5 Pro, and L3.

This is a purely subjective review - my gear, my ears, and my experience. Please take it all with a grain of salt - especially if it does not match your own experience.


I thought I’d list (before I start with the review) what I really look for in a new DAP.
  • Clean, neutral signature – but with body (not thin)
  • Good build quality
  • Reasonable battery life – at least 8-10 hours
  • Easy to use interface
  • Able to drive both low impedance and (within reason) higher impedance cans without additional amping.
  • Value for money
  • Enough storage to hold either my favourite albums in red-book, or my whole library in a reasonably high resolution lossy format (for me – aac256)
  • Gapless playback
  • Reasonable EQ
  • Bluetooth/Wireless if available
Did I get all of this with the X5iii, and more importantly was the X5iii an improvement on the X5ii? Mostly – yes, and I hope that some of the remaining shortcomings with the firmware will still be improved over time. What I also got was some additional features which really surprised me (we'll go through some of those too).



The X5iii arrived in a somewhat smaller box than its previous generations. This is a fully printed retail box measuring approx 110 x 165 x 50mm. The front has a full colour photo of the X5iii and the rear has a list of the main features (in both English and Chinese). Inside the outer retail jacket is a black rigid box and lid simply adorned the word “FiiO”. Removing the lid gives us our first look at the X5iii. Under this is another compartment which is home to the accessories.

Retail boxInner boxFull accessory package

The total accessory package includes:
  • One USB data and charging cable
  • One coaxial adapter cable
  • One leather case
  • One clear silicone “gel” type case
  • Quick start guide and warranty
  • Memory tray release key
  • The FiiO X5iii

The accessories are the usual quality I'd expect from FiiO) and the inclusion of both cases is really nice. I probably use the leather a little more than the clear silicone case – simply because it then fits the DK1 dock without having to do anything – and its also easier to slip out of the leather case if I want to use the K5.

(From FiiO's website), and I've included the old X5ii specs as well as the newer X7ii with AM3a module
ModelX5 3rd GenX5 2nd GenX7 2nd Gen
Approx current price$400 USD$238 USD$650 USD
Dimensions~ 114 x 66 x 15 mm~ 109 x 64 x 15 mm~ 129 x 67 x 16 mm
Weight186 g165 g212 g
DSD SupportDSD64/128DSD64/128DSD64/128
Use as external DACYesYesYes
Battery3400 mAh3300 mAh3800 mAh
Play time~10hr SE, 8hr bal~10hr SE~10hr SE, 8hr bal
DAC ChipAK4490x2PCM1792AES9028 Pro
Main amp chipOPA426x2OPA1612+BUF634Changes with module
SNR (H/O)≥115 dB (A-weighted)≥117 dB (A-weighted)≥116 dB (A-weighted)
THD+N (H/O)<0.003% (32Ω/1kHz)<0.001% (32Ω/1kHz)<0.003% (32Ω/1kHz)
Balanced?Yes 2.5mmNoYes 2.5mm (AM3A)
Output to 16ohm (SE/BAL)480 mW / 400 mW 436 mW200 mW / 380 m/W
Output to 32ohm (SE/BAL)250 mW / 240 mW245 mW150 mW / 400 mW
Output to 300ohm (SE/BAL)28 mW / 26 mW27 mW17 mw / 63 mW
H/O Impedance (SE/Bal)<1.0Ω / <3.0Ω<0.2Ω<1.2Ω / <1.7Ω
Line Out?YesYesYes
Digital Out?YesYesYes
Internal Storage32 GbNil64 Gb
External Storage512 Gb (256x2)512 Gb (256x2)512 Gb (256x2)
Screen3.97in IPS TFT 480x8002.4in IPS 400x3603.97in IPS TFT 480x800
OSAndroid 5.1FiiO ProprietaryAndroid 5.1
RAM1 GbN/A2 Gb
WirelessBluetooth and WiFiN/ABluetooth and WiFi


The main differences between the X5iii and X5ii are:
  • Touch screen instead of solely manual controls
  • Change to Android based OS
  • Addition of internal memory
  • Addition of wireless functionality
  • Addition of balanced output
  • Dual DACs


The build quality is really quite excellent on the 3rd generation of the X5. Compared to the original X5ii, the first thing you notice is that despite packing in a lot more hardware features, the size is actually virtually the same (X5iii is very slightly bigger and heavier, but it is marginal). The casing is the usual high quality material (stainless steel composite) you expect from FiiO, but this time there is a gorilla glass back, and of course the close to full sized IPS touch screen. The corners on the casing are nicely rounded, and in terms of overall size it feels right in my hand (not too large, not too small), and has a good weighty feel without being too heavy.
Left side – volume wheel and play controlsBottom – inputs and outputs
FiiO have put a lot of thought into this build, and on the left side of the device, they've done very well. There is their stepped volume wheel at exactly thumb height, and once I started using it, I suddenly noted how much I missed an actual volume wheel on the X5ii. Above it is the play/pause button, and below it is a rocker button which activates next/previous. All of them are in easy reach, are relatively discreet, and I have to compliment them on their design. It looks the part – and feels the part too. Unfortunately on the right side is where they have their first hiccup. The on/off (and screen on/off) button is on the right hand side directly across from the play/pause button. With one handed use, most of the time when pressing this button with my forefinger, I also inadvertently also press the play/pause or forward/next buttons. I don't mean to – its reflex. The on/off should be on top of the device – and incidentally this is where it appears on the X7ii (nice to see that FiiO listen to the critique's and improve the hardware!

On the right side about half way down are two “sim” slots (recessed trays akin to the sim slots in mobile phones) which hold the microSD cards. The X5iii at this time can take 2 x 256 Gb cards giving a total memory of 256 + 256 + 32 or 546 Gb of storage (less the operating space for the internal system). You access the cards using an included push tool (or a paper clip). I personally find it ideal as I'm not continually swapping cards in and out. The trays fit absolutely flush and are clearly labeled 1 and 2.

Right side – Micro SDXC trasy and on/off buttonRear gorilla glass
At the top of the X5iii is nothing (and in my personal opinion this is where the headphone / line-out ports should be). At the bottom from left to right are the 3.5mm headphone out, 2.5mm balanced headphone out, USB port, and switchable 3.5mm line or coax out. Unfortunately this means that when docked with their DK1, there is no way to connect to the headphone ports. A pity – because I am sure others would also consider using the dock this way. Otherwise the ports fit nicely and snugly, and the USB out is compatible with both the DK1 and K5 docks.

The 4 inch (3.97) IPS TFT screen is superb compared to the X5ii, both clearer and more vibrant. It has a wide viewing angle (almost 180 deg), and my only critique is that it very easily picks up finger prints and smudges. Low light visibility is excellent, but with full sunlight (like most touch screen devices), you have to shade the device for any decent viewing legibility.

Internally the X5iii is equipped with two top-of-the-line AKM AK4490EN DACs (one for each channel). FiiO chose this DAC for its format support (32bit and supports all PCM and DSD formats), and also for its smooth “velvety” tonality whilst still maintaining high resolution. The AK4490EN also has impressively low THD and high SNR measurements. Along with the dual DACs are dual crystal oscillators which FiiO state help in reduced jitter, improved clock accuracy, stability and virtually no sampling rate conversion artifacts. For amplification, the X5iii uses two dual channel OPA1642 chips for its low pass filtering stage, and a custom-made OPA426 chip for amplification.

The X5iii is powered by a 3.8V 3400 mAh Li-polymer battery which provides approximately 10 hours use in ideal conditions using the 3.5mm single-ended output, or around 8 hours if using balanced output. In my tests this was achievable using IEMs with the screen mostly off, and the DAP set to play continuously in FiiO's Pure Music mode (with a lot of the Android system resources disabled). This obviously does not reflect real-world usage, so expect less if you're constantly using the screen, or using apps that may have a higher draw on the battery. For my personal use (single-ended) I can easily get 8 hours out of a fully charged battery with normal use, and this has been sufficient for day to day use.

The X5iii has the ability to quick charge from suitable 9/12v high current charging devices, and this essentially means you can fully charge the X5iii in approximately 1.5 hours from an appropriate charger. Normal charging only takes a little over 3 hours from a 5V/2A charger – which is more than enough for my use. You can also play and charge at the same time if using a portable battery pack.

FiiO's output specs and recommendations show that the balanced output has actually been throttled back, and is actually lower than the single-ended output, which is somewhat strange. But I appreciate they are trying to cater more to the people who see balanced output as an advantage in terms of lower crosstalk etc – whilst still catering mostly for portable use. I quoted the power output figures in the spec table earlier – but what does this mean in terms of real world conditions? I chose to utilise 4 different IEM / earphone / headphone combinations to see what the specs really meant.

For each test, I used the excellently mastered new track “The Same Asylum As Before” from Steven Wilson's new album “To The Bone” - for no other reason than I've just bought it and have been enjoying getting to know it. For each test, I aimed to get to my average preferred listening level of 65-75dB with peaks well under 85 dB. For this I used my trusty calibrated SPL meter.

First up was FiiO's own 28 ohm, 106 dB/mW sensitivity F9 IEM. Why the F9? Simply because it is an easy load to drive, sounds absolutely excellent, and reflects an average load for everyday use. 45-50/120 on the X5iii was sitting me easily within my preferred sonic range on low gain – so plenty of head-room.

Next up was HiFiMan's flagship RE2000 IEM at 60ohm and 103 dB/mW sensitivity. This represents a load with higher impedance and lower sensitivity, and it did require 55-60/120 to reach the same listening volume. Again though – plenty of head-room, and the RE2000 on the X5iii sounded stunning.

OK – lets go with a harder load. This time an ear-bud – VE's flagship Zen2 is an incredible sounding ear-bud which while relatively sensitive at 108 dB/mW, has a much higher impedance of 320 ohm. This was much harder to measure, and I don't know if I got this completely accurate, but 60-65/120 reached my ideal listening level and again I could detect no issues with the X5iii's amplification sounding weak.

Final test – and this time lets step beyond the likely and try something a lot will consider slightly ridiculous (I don't). The HD800S is 300 ohm and 108 dB/mW. Its my real test as I sometimes like to move around the house with these headphones so for me it is a realistic test. This time 75-80/120 was hitting my ideal listening level with this headphone (again low gain). More importantly, fidelity was really good.

OK Paul – but how do you know you were getting an acceptable level of fidelity from each earphone? Well that is the simple part. I also have FiiO's A5 headphone amp here. It is quite neutral, and can output 150 mW into a 300 ohm load. I've used it before with the HD800S and it has very much impressed me as a portable device. So once I'd found my ideal listening level with each transducer, I simply used test tones to replicate the same volume with the A5, then switched between the two. None of the combos sounded superior with the A5, except perhaps the HD800S where the bass was very slightly different with the A5 included (and this could have been expectation bias). What I will suggest is that the X5iii's power output is actually pretty decent for most portable loads. Just don't expect to drive really power hungry cans – and if you might be, consider the A5 as a very worthy partner.

The X5iii comes with both Bluetooth 4.0 and 2.4 Khz Wifi capability. Performance on both seems pretty good. The Wifi receiver is not as good as my iPhone. I'm sitting in my study, the router is around 8-10 meters away, but through two walls. My iPhone SE is showing full bars, the X5iii is about 75%. Connection is solid and stable, and perfectly good for streaming or downloading apps or updates. The iPhone is slightly quicker. So the X5iii is good – but not perfect.

The Bluetooth connectivity is actually better than I expected. I used my FiiL Diva Bluetooth headset. Connection was straight forward – easily recognised and paired. And I can actually install the Android FiiL+ app (although the play store version says it isn't compatible – so I just downloaded and install the apk manually). I can also use all the headset's features including volume and track control, and can easily get past 10m (it starts breaking up about 13m) distance. The X5iii is showing AptX connection with the FiiL, and I have used these outside walking with X5iii in my pocket, complete wireless freedom, and a smile on my face!

The UI is standard Android and I'm not going to cover all the standard features (battery meters etc), and concentrate instead on FiiO's Pure Music app. You have the choice of retaining full Android functionality or going into an exclusive mode called Pure Music where a lot of the non-essential Android apps are turned off, and FiiOs own app takes over. I am currently using Pure Music V3.3.8.

Home screenLocal musicFolder view
First view of the Pure Music app is a home screen (which you can configure in settings). At the top left is a settings icon (to take you to the Pure Music settings). At the top right is a search icon. In the middle is your now playing graphic. Below are 3 icons (configurable) which will take you to your choice of playlists, local music (accessing music via tagged database or vis folders), DLNA, recently played, most played, or recently added (you can choose 3 options). You can also have lists below these icons – the nice thing is that you decide how you want things to display. Clicking on the now playing graphic (or the note icon beside it) takes you to the main now playing screen.

The main now playing screen shows full sized album art. Tapping on this will cycle a lyrics screen (more on this later), an information screen showing title, album, artist, and format / bit-rate / sample rate, or a V-U meter. Below the album art is a scrubbing slider (or fast forward / rewind). Then below this are the traditional play/pause, next/previous icons (or you can use the physical buttons). At the left of these is the play through choice icon (straight through, shuffle, repeat etc). At the right is a single circle graphic with 3 dots, and this accesses the other features you'd likely to need from a now playing screen – including EQ, marking a track as a favourite as well as accessing the favourites screen, bluetooth, deleting a track, and accessing full information about the track on a single screen. At the very top of the now playing screen are two icons – right is a search icon, and left takes you back to the home screen. Swiping the middle of the album art right advances a track, and left goes back one track. Clicking, holding and moving up or down from the very right edge of the album art adjusts volume. Swiping right from the far left of the album art brings up the current playlist.

Now playing screenPlaylist viewQuick menu
The local music screen gives access to tagged features within the library – including all songs, artist, album, genre and folder access. If you're playing a track while you're accessing this, it appears at the very bottom of the screen along with its controls (and tapping this takes you back to the now playing screen). To the right is a small button with 3 dots. This accesses more features including the ability to sort and also to perform mass operations (for the likes of building playlists). I don't really use this – as I find it easier to build the few playlists I need manually. Navigation is pretty easy, and once you are in a menu, going back is a simple matter of using the back button at the very bottom of the screen.

VU MeterEQLyric menu
The EQ screen is an interesting one which I do use often, but find frustrating at times. There are presets, and a custom option (but you can customise all the presets, and there is a reset button to return them to their original state). There is a 12 dB swing (-6 / +6) which allows plenty of room for tweaking and 10 bands. The issue is that only 5 sliders are shown on screen at a time, so you have to slide left and right rather than having them all on the screen together. I realise this is a limitation of screen size and I can't find a way to rotate to use landscape. The good news is that the entire 20 Hz – 20 kHz frequency display is shown on the entire screen, so this does help when you've inadvertently hit the wrong slider. Note to FiiO though – a label on each slider would help!

Pure Music settingsPure Music settingsPure Music settings
FiiO's Pure Music settings are pretty comprehensive, and I'll show them in 3 screenshots rather than listing them all. The usual features are all covered including playing through folders, gapless, channel balance and gain. There are also some new ones like inclusion of Viper for Android effects which I'll cover shortly. You can also choose your preferred theme (now 3 options), lockscreen, and personalise many of the features. A notable exclusion is replay gain, and the ability to use landscape mode (please FiiO – address this), but otherwise most other settings are addressed pretty well.

Rather than go into depth with any more standard settings, lets look a little closer at some of the other features – some of which I didn't expect, but which are actually quite brilliant.

The first one I want to cover is something I didn't expect to use, nor actually find useful, When you are in play mode, you can click on the cover art, and bring up a lyrics screen. Tapping on the “search for lyrics” triggers an internet search for the correct lyrics and then saves it as a file. Through another icon/button on the same screen you have access to more tools so you can synchronise the lyrics properly. Its a pretty cool feature, and works well for most mainstream music – and the only thing I wish was easier was to select the sources to be searched.

The next is the Viper effects. These are the set of effects commonly known as Viper for Android, and developed by Euphy Wong – initially for desktop, then later for mobile use. The effects are somewhat similar to some of the enhancements in the Neutron app, or Cowon's BBE. Some are offered free, and others you have to pay for. If you aren't a tweaker, you may find them superfluous. But when the mood takes me, I find the Field Surround and Differential Surround are both really good if you want to widen the sound stage. There are other setting for bass, clarity, volume equalisation – quite a long list really.

Some of the Viper effectsNeutron app running
You also have DAC mode, and coupled with FiiO's driver, I've had no issues connecting from my Windows 10 environment. Unfortunately I'm having a few issues with my Linux build at the moment and all the recent FiiO devices have issues with my desktop when using Linux – but I regard this as more of an issue with my current OS (Mint), and I'm confident when I return to a straight Debian set-up, they'll be solved. I've been using the X5iii with the K5, and no issues with connectivity, nor with selecting the appropriate output. One thing I was pleasantly surprised with was that I could originally connect the X5iii via USB port to my iPhone SE and have the iPhone outputting digitally to the X5iii's DAC. I seem to have lost that functionality with an iOS update – but you may have the ability (either iOS or Android) to use the X5iii as DAC. Its just a matter of trialling it – if it works, then its another nice option.

Gapless – has been a bit hit and miss. FiiO get it working, then sometimes during updates they'll tweak something which causes a reversion to functionality. Usually its fixed again relatively quickly. Currently gapless is 99% of the way there. There is the tiniest of micro-gaps. It doesn't bother me at all but if you are the kind to be completely OCD about having it perfect, you may want to consider something else.

Use of other apps. If FiiO's player isn't to your liking, you can install practically any other music playing app. I've been using Neutron from time to time – mainly because of its wealth of settings, and because I've come to know it pretty well. Its also very stable – sometimes more so than the FiiO Pure Music. But one of the beautiful properties of the X5iii is that at its heart it is an Android player with very good hardware. If you don't like the player – install something you do like as a front end.

I did test streaming with Tidal HQ (even bought a subscription so I could test properly. I was able to configure off-line download to the external memory cards, and it worked pretty well except for one small issue. From time to time it would “hitch” or “stutter” (not often for me – but definitely occurred). I know this issue has also occurred with other players (for example the Cayin i5), so I wonder whether this is a FiiO issue or a Tidal one.

I've also tested the various DAC filters (the X5iii includes sharp roll-off, slow roll-off, short delay sharp roll-off, short delay slow roll-off, and super slow roll-off). I hot swapped between the filters, and to be honest, I cant hear a difference. Could be that my hearing simply isn't sensitive enough. Anyway for me they don't really warrant playing around with. The research I've done into filters (essentially reconstruction filters which play in the ultrasonic regions, and are designed to cope with ringing and possible quantisation noise) suggest that most of them are only going to change things at 1-2 dB max at 15 kHz or higher. Thats beyond my hearing, and due to the frequency and the small change, should be beyond most “normal” people's hearing (and yes that was #sarcasm+jest).

I was unable to test DLNA or DSD over DOP.

I'll start first with support, and in my experience FiiO is one of the new breed of companies whose idea of product support is one of collaborative development. They are extremely active in the community, and are always listening to our requests, and trying where possible to implement new features or fix bugs. Unfortunately at times this means that the firmware isn't always stable (which is why the use of other apps is sometimes really important). I've heard a lot of critique about FiiO using its customers as beta testers, and breaking things more often than they fix them. I don't personally have the same experience (most of the time this X5iii has been very stable). It might be worth pointing out that I am more a traditional user though – relying less on streaming, and more on music loaded to the cards.

I have (at various times, and usually with new firmware) experienced crashes with Pure Music, and these can sometimes be quite annoying. I have found that FiiO has been quite responsive in coming up with solutions though, and I'm fairly tolerant as long as the device is still functional.

Included in the known issues are:

  • Gapless playback has a micro-gap (very small)
  • There is no replay-gain
  • Some have reported occasional lagging and stuttering especially with larger files (DSD or extremely high-res). I have not experienced this myself – but all of my files are generally aac256 and I have an entire library on a single 64Gb card
  • Occasionally – especially when awaking from sleep mode – it can take a couple of seconds for the 2nd micro SD card to be recognised.
  • Start-up time is fairly slow (around 30 seconds).
  • Output to 3rd party apps appears to be down-sampled with most (the exception being Neutron). Personally I don't find this being an issue as I know I can't tell the difference anyway. The issue appears to be more the integration of external apps rather than the actual X5iii itself.
  • Some stuttering with Tidal – appears to be a Tidal issue (have seen similar with the Cayin i5)


The following is what I subjectively hear from the FiiO X5iii. Some of you may find this section a little limited, so I’ll give you some insight into the way I’ve changed my opinion on how to describe the sound with any competently made DAC, DAP or amplifier. The problem with trying to break the sonics down to bass, mids and treble is that DAP / DAC / amp is designed (or should be designed) to be essentially flat across the frequency spectrum. If it has enhanced bass, then isn’t it adding colouration that should come from the headphones or EQ or recording? Likewise, I won’t comment a lot on sound-stage, as this is primarily a by-product of the actual recording, or the transducers you’re using.

So how do I go about describing it? Well my gear isn't great for measuring DAPs but judging by the correspondence from FiiO, and their own measurements, I’m pretty confident the X5iii is very linear in its frequency response. What I will do is comment on overall tonality and resolution, and also expand further when comparing the X5iii to some of the other DAPs I have experience with.

For the record – on most tracks, the volume on X5iii was adjusted to give me an average SPL around 65-75 dB. Tracks used were across a variety of genres – and can be viewed in this list When I tested side-by-side with other DAPs I used test tones, and an SPL meter to volume match. I used the same track, and had the players set up so I could rapid switch. Testing was performed with LZ's Big Dipper.

X5iii General Tonality

This is actually an easy one – because the X5iii is (for me anyway) quite unique among the DAPs I've heard. I originally thought it was quite warm, but its not so much warm as rich and smooth. But isn't that warm Brooko? Nope – the low end is not enhanced (to me anyway) and there is no added bass response. I've seen others describe the X5iii as warm, or muddy. Or veiled, and I'm afraid thats not what I'm hearing. What I have found instead is that the X5iii actually has an extremely high level of resolution. With a headphone like the HD800S (or indeed any decent reasonably well balanced IEM) all the detail is there, and pretty easy to discern. Where the X5iii differs from some other DAPs I own is that the tonality is silky smooth – no sign of harshness or glare. It's funny too – I've never really noticed the glare on other DAPs before, but when comparing side-by-side, the X5iii just seems to have a really nice tonality.

Resolution / Detail / Clarity
Clarity and resolution is excellent on this DAP, its just not as “in your face” as some of the other DAPs I have. I've gone over my test tracks 100's of times now, and the X5iii is not missing any of the detail or resolution of my other “more linear sounding” DAPs. Its just the presentation of that detail. When playing PF's “Money”, all the nuances from the cash registers are present – they just don't have that artificial edge to them. In “Sultans of Swing” I can still hear the clicks when Withers taps his drumsticks together, but there isn't that extra heat or emphasis. What I hear is more organic, more balanced, more tonally pleasing.

Soundstage / Imaging
Why is this section even here? The perception of sound-stage in a DAP is a result of the music you listen to (the recording) and the transducers you use. The DAP has virtually nothing to do with it, as long as it has decent crosstalk measurements, and there is no DSP involved. I often laugh quietly to myself when I read reviews claiming one DAP has more sound-stage than another. For the record, I volume matched the Cayin i5 and X5iii (same DAC sections), and tested my binaural tracks. Both sounded pretty much the same. And with the HD800S or the Big Dipper IEM, the perceived sound-stage width/depth was the same on both, and only influenced by the actual transducer being used. The one advantage the X5iii has in this area is the ability to use the Viper settings with Pure Music (you can also get similar effects with Neutron's DSP settings). Both can shape the perceived stage (very nicely in fact).

X5iii vs X5 Original
The original X5 was about the size an iPod Classic, but with better internals and a mechanical wheel. In terms of size, the X5 iii is almost exactly the same size as the X5 original. They both have dual micro SDXC slots, both can play most high-res formats (the X5iii can do native DSD decoding which the original X5 can't), both have similar output options (coax, line and headphone outs), and both have similar battery life (X5 original is slightly better at 10-12 hours vs X5iii's 8-10 hours.

The X5iiis advantages come with it's wireless connectivity options, touch screen, separate wheel for volume control, balanced output, more feature options via the Android interface (apps etc) and a better screen resolution. Power output is very similar (single-ended).

Sonically the two are practically identical, and in fact the X5 original is closer to the overall sonic signature of the X5iii than any of FiiO's other players. There is still a slight edge to the upper mid-range and lower treble which seems to be softened on the X5iii.

Gong back to the X5 original has actually been a really good exercise, and I've been surprised (all over again) at how good it sounds. Is the X5iii a big step up? Well, sonically I'd say no – but in virtually every other category – yes. It simply brings a lot more features, while retaining that original silky smooth but balanced signature.

X5iii vs X5ii
The X5 2nd gen (X5ii) again is very close in size to the new X5iii, and shares (once again) remarkably similar physical dimensions (the X5iii is marginally larger and heavier). They again both have dual micro SDXC slots, both can play most high-res formats (both handle DSD this time), both have similar output options (coax, line and headphone outs), and both have similar battery life.

The X5iiis advantages again come with it's wireless connectivity options, touch screen, separate wheel for volume control, balanced output, more feature options via the Android interface (apps etc) and a better screen resolution. Power output is similar (single-ended), although I do need more power on the X5iii to volume match with the Dipper. The X5iii does have one advantage (feature wise) compared to the X5iii and that is working replay gain. Both also have a reasonable search function.

Sonically its amazing how many mis-conceptions disappear when volume matched and quickly switched. These two are a lot closer than I expected. The X5iii is slightly smoother but its definitely not any warmer. The X5ii still sounds slightly more vivid, and actually sounds a little cleaner (again its that very slight smoothing that the X5iii brings).

Once more I'm pleasantly surprised how the X5ii performs, and given that you can now buy a new X5ii on Amazon for only fractionally more than the new X3iii, it is even more a stellar performer than it originally debuted – especially as the fw matured. Of course the advantages of the X5iii still remain with its Android UI, features, and wireless connectivity. Those looking for absolute clarity are possibly better staying with the 2nd generation model. For me though, the combination of features (esp Viper or Neutron) are still worth the extra coin, and the wireless (Bluetooth) is really useful with my FiiL Diva.

X5iii vs X7ii
This one should be interesting. The X7ii is if course the update to FiiO's flagship DAP. Its only been out a couple of months, and already has a big following. The X7ii is larger, mainly due to it's interchangeable amp section. But the design of the X7ii now borrows heavily from the X5iii, and includes dual expansion slots now, the volume wheel, and even the software is essentially identical. The same apps, wireless connectivity (although the X7ii adds access to the 5GHz band), access to balanced output (although the X7ii is more traditional and doubles volume output where the X5iii is weaker) – in fact the X7ii is essentially an X5iii but with different DAC (X5iii's dual AK4490 vs X7ii's ES9028 Pro). The other major difference in terms of hardware features is that the X7ii can utilise the new AM3a amplifier unit, but also any of the previous amplifier modules (including the high power AM5).

Sonically the difference is not huge, but is noticeable, and its a repeat of past comparisons. The Sabre DAC of the X7ii is noticeably more neutral and appears cleaner because of it. The X5iii in comparison has that slightly smoother rich tonality which people will either love (find it musical) or dislike (citing it as warm). This is not a night and day, and really comes down to preference. I can absolutely see the extra value in the X7ii – and especially if you're using the one device to drive a variety of headphones, and likely to utilise the functionality of different amp modules. For me, if I had to choose one at the moment, and my primary portable use is with IEMs or my FiiL Diva, it would be the X5iii simply because I genuinely like the tonality (which surprised me a little), and I also prefer the slightly smaller form factor. But you can't go wrong with either (two thumbs up FiiO).

So what about another Android based DAP – well fortunately I happen to have Cayin's i5 with me.

X5iii vs Cayin i5
In terms of size, the two are very similar with the Cayin being slightly longer. Cayin only supplies one measurement of power output, so I tested both with my HD800S and playing same track at max volume, the i5 was able to supply 10 dB more volume than the X5iii (measured with calibrated gear). One slightly interesting quirk about the i5 is that the screen has to be on to change volume, where the X5iii works as it should. Cayins UI is based on a customised version of Hiby, and things like scanning are very fast (quicker than X5iii). The UI itself can be a bit easier at times to follow than FiiOs and other times more complex (getting to EQ requires more steps), but on the whole both are comparable. The i5 uses an older Android 4 version where the FiiO is Android 5. Wireless performance on both is comparable – however neither have as good wireless connectivity as my iPhone. Bluetooth range and stability is slightly better on the Cayin i5, but both are good for portable use with a headset. I was able to install 3rd party apps like Neutron and Tidal on the i5. Both performed well – with Tidal having the same issues on the i5 as the X5iii (intermittent stuttering). Both can be used as an external DAC, and I had no issues with either (after installing drivers) on a Windows 10 PC. For general ease of use and comparing the default Pure Music (X5iii) to Hiby (i5), my personal preference would be toward the X5iii. The i5 has also (over time) been a little more quirky – at odd times not playing until closing and restarting, displaying wrong album art etc

Sonically the two are very close and I guess this is the result of the same DAC hardware (AK 4490). I spent a lot of time going between the two and when volume matched, I'd say they sound practically identical – I certainly can't tell them apart in a blind test. At first I thought that there might have been a little more extension with the i5, but when I got my wife to help me blind swap I was completely baffled over which was which (more evidence of sighted bias at play). Both sound fantastic with a rich and smooth tonality that I personally find intoxicating.

In terms of overall preference, its a bit of a tough one for me. The price now on both units is pretty close – you can pick up an i5 for $470 so its much closer to the X5iii's 399 RRP. Both have their strong points. I don't tend to need 2 micro SDXC slots (I use aac256 on my portables anyway, so storage is never an issue). For me a balanced connection has more advantage with additional power (and the X5iii's is not configured that way). Both can power my HD800S with headroom to spare and I'd simply use my A5 amp anyway if I needed it. My personal preference goes with the slightly cheaper, slightly less quirky X5iii. Both have their individual personalities, neither is perfect, but the comparison is really close – and I would really be happy with either.

EDIT Nov 2017 - I've been reviewing the i5 over the last couple of weeks, and it has involved active comparisons with the X5iii once again. With the latest i5 firmware there is now a slight difference - the i5 appears to have a very slight shift in tonality - more toward neutrality - a little less warmth. The change is really subtle though. Definitely still more warm than neutral to me.

I've tested this. The balanced output actually has slightly less power than the single ended, so no advantages there. So what advantages to balanced output are there? Balanced must be better right? Not really. Balanced will chew the battery quicker, and both outputs would drive practically any IEM into the regions of deafening you. Both are essentially over-kill.

Now lets look at the real differences - those bits that people make claims on. Remember how balanced is always cleaner, darker, more spacious, wider sound-stage .......Lets look at cleaner first. SNR on SE is 115 dB and on balanced is 111 dB. Both are beyond what we can hear - so no difference. Both have THD measurements at 0.003% = beyond our hearing. You'll get a magnitude more distortion from your earphones. Now the important one - crosstalk (channel separation). SE is 73 dB and balanced is 98 dB. That must make a big difference - right?

I'm going to quote something bookmarked a long time ago:
The FCC minimum channel separation/crosstalk spec for FM Stereo used to be 29.7dB...yes, that's right, 29.7. It had to do with how the signal was generated and handled, but 30 - 40dB wasn't hard to achieve, and 50dB wasn't uncommon.

The bulk of what is perceived as stereo separation happens above 20dB with decreasing detectable improvements above 30dB or so. It's almost impossible to detect separation improvements above 40dB. Localization of a phantom image depends less on channel separation and much more on relative intensity and inter-aural time delay of the sound, and human hearing response at different angles.
So....long answer...separation above 40dB doesn't improve sound quality, below 40dB it slowly degrades, the final separation is equal to the device with the least separation in the system. Once degraded by a device, no device following it can restore separation.
As you can see, SE crosstalk at 73 dB and balanced at 98 dB actually means nothing - we can't hear it.

What essentially happens is two things.
People read the specs, and tell themselves balanced must sound better, and thats what they talk themselves into. In a blind volume matched test, they won't tell a difference (unless impedance changes frequency).
Most people don't volume match, and we are terrible at volume matching by ear (which is what a lot of people do). Most balanced circuits output a lot more power by design - therefore they are louder. People saying they hear a difference are often simply listening to one louder than the other. And we know louder is perceived as sounding better. Int his case the X5iii's balanced output is ever so slightly weaker.
There are two other possibilities for differences:
The balanced circuit actually sounds better by design (unlikely given FiiO's expertise)
Impedance mismatch can affect frequency response for multi-BA driver set-ups (rarely happens with dynamics). You'll note the <1 ohm (SE) vs 3 ohm (bal) output.
Either way, if you're buying the X5iii because it has balanced output, and expecting a sonic miracle, you'd be better with EQ.


So how do I see the overall value of the X5iii? Quite simply, it reaches that overall performance which has me definitely recommending it at its current price point. In FiiO's current range (X1ii, X3iii, X5iii and X7ii), it sits as the best overall value DAP (features for price) – especially if you are mainly using it for portable use and easier to drive earphones or headphones. I also have not encountered any DAP (and admittedly my experience with other brands is not extensive) which has more features and better sound (subjective) for the price.


My apologies, once again an overly long review, and my intention in future is to try and be more concise. Also my thanks to FiiO (especially Sunny and Shadow) for their support with my questions, for supplying the review sample, and for including me in some of their testing programmes).

The X5iii is a very well presented DAP with good build and some really good hardware design features (volume wheel, recessed SDXC trays), and just a few minor (IMO) fails (position of the on/off button, limited RAM). It feels great in the hand, has good implementation of both Bluetooth and Wireless, and the touchscreen seems quite responsive. It has the ability to store on 2 external sdxc cards. Power output is more than sufficient for IEMs and portable devices, and I've found its output perfectly OK with both my HD600 and HD800S. It also has a balanced output option – although this has slightly weaker output than its single ended output.

In terms of UI and features, the X5iii is pretty much up with most modern DAPs and includes a couple of extras (Viper DSP settings & also a lyrics search) which I wasn't expecting to find. The UI is easy to follow and relatively stable, although like most Android devices I've seen, as its good days and bad. For my personal use, I've had the occasional crash – but overall the fw has been relatively stable (YMMV depending on usage).

Sonically (and this is subjective) the X5iii has a rich and smooth tonality which I know many will call “warmish”. It has no issues with resolution or clarity, and I personally love the overall signature from the AK4490 DAC.

So far it has ticked all my personal boxes in what I look for in a DAP, and at the price of $399 I personally find that in terms of tonality, features, usability and performance – it is one of the “best in class” in terms of overall value.

4 stars from me. Possible improvements would include better button layout, a balanced output with increased power, more ram and more on-board storage.

Again – thanks to FiiO for providing me with the X5iii for review.

Hi. The review at one point mentioned that I5 outputs 10db more power than X5iii via single-ended. The problem is that Fiio advertised that X5iii outputs around 250mW compared to I5 which outputs only 190mW. So does that mean that I5 is actually much more powerful than X5iii?
Pros: Light and Portable
Incredible Value Proposition
2 micro-SD card slots
Easy to use GUI
Great sound quality
Cons: Not able to output high resolution music via USB (yet...pending a possible firmware update)
Having finding myself in need of a lower cost portable digital-to-analog player, I began my search for a reasonable solution. If you've been around Head-Fi, you are most certainly going to stumble upon FiiO's recent upgrade to their venerable X5 DAP, the X5 Mark III. Priced at only $399, don't let the incredibly reasonable price tag through you off; you are getting some serious technology and audiophile level sound quality in this little wonder.

Player 1.jpg

At the heart of the FiiO X5 Mark III are dual AKM AK4490EN DACs using their "Velvet Sound" low distortion architecture with digital filtering and 32 bit processing. Quite impressive technology as I've been a big fan of AKM DACs and really loved their implementation in the full sized $2500 desktop Bryston BDA-2 digital to analog converter. So I was happy to see that FiiO selected AKM to make up the guts of their famous player.

Also included is a very much welcomed dual micro-SD support. This allows you to insert up to 2 micro-SD cards into the FiiO X5 MkIII and really load up all of your favourite albums (regardless of file sizes). You can add a whopping 512 Gb of additional storage room on this player; this was even more than many uber-expensive DAPs costing $2000 or more. Also included is the ability to drive your in-ear monitors or headphones in balanced mode through the 2.5mm headphone jack. Again, I was thoroughly impressed with the options available here that are typically reserved for digital-to-analog players costing several thousands of dollars!

The full list of specifications are:
FiiO X5 III Specs.jpg

Build quality is excellent and unlike my previous player; the FiiO X5 MkIII comes in at a very light 187 grams. So it's very portable and easy to carry with you while you travel. Also included is a very handsome leather case that will protect the player and enhance its visual appeal at the same time! Another big feature to note is that this player supports Tidal Lossless Streaming. Just download the App from the FiiO Store and log into Tidal and you're off to the races. Again, for a player costing only $399 US, I am thoroughly impressed with what the folks at FiiO have been able to stuff into this small wonder and keep their price very competitive!

For this review, I used both in-ear monitors and full sized headphones that I had on hand that I typically use for portable use. I played lossless music from Tidal, to some of my favourite DSD test tracks. And with everything, the X5 MkIII really outperformed my initial expectations.

I absolutely love my custom Empire Ears Zeus ADEL XR in-ear monitors. These in-ear monitors allow the user to switch between the -R or warmer XIV versions. I find these IEMs about as transparent as I've ever come across and often use them in reviews for portable equipment. Now some might think pairing a pair of $2700+ in-ear monitors with a $399 DAP might really hold them back, but based on what I heard when playing my DSD recording of "Jazz at the Pawnshop" was as exciting and fulfilling as it ever was with these top notch in-ear monitors. I found the sound staging, detail retrieval and overall sonic enjoyment to be right there with many DAPs I've heard/owned costing north of $2000! Now how's that for value! The noise floor was incredibly low and the transparency incredibly high. You can have your cake and eat it too! Everything from the small nuances of the background chatter to the decay on the cymbals were perfectly laid bare with this combination.

jazz at pawnshop.jpg

Next up, I decided to use my full sized AKG flagship headphones, the K812. I absolutely love these headphones and was curious how the FiiO X5 MkIII drove full sized headphones. For this test, I decided to go on to WiFi and use the downloaded Tidal App from the FiiO Store. I noticed that the classic 80's Bryan Adam's album "Reckless" had recently been updated with a new anniversary remaster. Going from the incredibly efficient Empire Ears Zeus ADEL IEMs to the AKG K812s did require me to certainly crack up the volume setting on the FiiO X5 MkIII player, but I have to say that this player was able to drive both very well and without the need of me having to put my Chord Hugo 2 in between the X5 MkIII and my K812s. The overall sound was full and energetic and the ability of the X5 MkIII to control the drivers on the K812 headphones was readily apparent! This combination took me back to high school when this amazing album was first released and for a quick on the go setup, the FiiO X5 MkIII certainly fit the bill!


I did also include my recently acquired Chord Hugo 2 in between the FiiO X5 MkIII DAP and my headphones/IEMs and for the most part things went off without a hitch. However, when I tried to play high resolution music (anything north of 96kHz) the player would not output sound. I've read that the engineers at FiiO are looking into remedying this in a future firmware upgrade and I certainly hope that they do as this one issue I felt held the player from hitting every nail on the head. Fingers crossed this is released soon. That said, the GUI (graphical user interface) is quite easy to navigate and figure out...even for me, a sworn Apple user!

Player 2.jpg

Overall I was thoroughly impressed with the Fiio X5 MkIII DAP! The value proposition is simply off the charts. If you consider the outstanding build quality, dual AKM DAC chips, balanced operation, Tidal Support, dual micro-SD card inputs and incredibly impressive sound quality, this product is a no brainer to recommend! This player has certainly passed the "put your money where your mouth is" test as I will most definitely be purchasing the review unit. I strongly suggest you check this player won't be disappointed!
Pros: a variety of accessories included (e.g. silicone and faux leather cases)
- build quality
- nice looks
- high ergonomics & compact size
- no Wi-Fi interference
- clear signal (in case of most IEMs/headphones)
- neutral, direct, smooth and pleasant tuning (neither too analytical nor too musical) with high resolution, good separation and much air
Cons: low performance of internal storage, card readers, Wi-Fi and OTA update servers
- audible hiss (when using IEMs of high sensitivity)
- average battery life
- amplifier section could have been better – when using the line out, dynamics and resolution are improved
Third generation of FiiO X5 offers plenty of features. It utilizes dual AKM AK4490 DAC, quad-core SoC, a 4-inch touchscreen and runs on Android OS.

Third revision of X5 brings a lot novelties. Rotary dial has been replaced by a touchscreen and it comes with a single-band Wi-Fi module added. Moreover, streaming is supported and there’s a Bluetooth transmitter with aptX codec support. New X5 version is powered by dual Asahi Kasei DAC and the Chinese company decided to restore the internal memory (32 GB), which can be further expanded via 2 microSD slots (up to 256 GB each).


The device is packed in an aesthetic box. The accessory set is as follows:
  • silicone case
  • faux leather case
  • USB-microUSB cable (100 cm)
  • coaxial adapter
  • card slot opening tool
  • quick start manual
Silicone case is thick, smooth and elastic. The included faux-leather case exposes the bottom flank and the volume dial.



New X5 looks completely different than its predecessors. It more resembles FiiO X7 or Astell&Kern DAPs. X5 III is a device that reduces the gap between high-class digital audio players and smartphones.

Front is occupied by a nearly 4-inch IPS display, which is further reinforced by hardened glass. The borders are rather wide and the screen resolution is 480x800 pixels (235 ppi). Color reproduction is fine, viewing angles are wide and contrast is just average. Housing is made of CNCed aluminum.

Build-quality is awesome, better than in 1st gen X7. The device is massive and built like a tank. Materials are of high quality and the device’s also pleasant to look at. For me, it’s the sexiest FiiO’s device (it won the Red Dot Design Award) and I like it more than Astell&Kern’s products.



Ergonomics and operation

Comfort of handling is fine, with some minor inconveniences. One also needs to remember that X5 III is a decent-sized device (11,4 x 6,6 x 1,5 cm), which weighs almost 200 grams.

X5 is meant to be held in the left hand. User can then comfortably operate the volume or navigate the tracks, while the right hand can be used to use the touchscreen. Elements are placed favourably, but the buttons are too soft, yet offer precise click. Accidental presses happen when lifting the device, but it’s easy to block that function (with the screen turned off) in the options menu.

All connectors are grouped at the bottom flank, which is a convenient decision as they can be easily distinguished and their position easily remembered. Card slots are placed on the right side and this time FiiO decided to use trays (like in smartphones ; a special tool is required for opening) instead of slots. Luckily, there are also 32 gigs of internal memory, while two microSD slots are compatible with microSD cards up to 256 GB.

Battery life is average for an audiophile DAP – up to 10 hours when using a headphone output. During intense tests X5 lasted for 7-8 hours with 3 hours Screen-on-Time. I used various headphones and earphones, played music from internal and external storage, streamed via Wi-Fi and Bluetooth and switched between miscellaneous modes and functions.

During playback the device does not heat up much. Even after a long-lasting playback it is barely warm.


Operating system and benchmarks

3rd gen X5 is powered by Google’s Android 5.1.1 Lolipop. The operating system is therefore outdated – it’s a shame that FiiO didn’t use at least 6.0 Marshmallow version, which features Doze sleeping algorithm.

Booting takes a long time, but when the device is finally ready to use, the system works fine. Android is almost clear and adapted for a DAP function. System is stable, but can be laggy, especially when launching an app. X5 scores 26322 points in AnTuTu 6.2.7 and GeekBench rates it at 500 points in single-core test and 1004 points in multi-core benchmark.

Graphics looks like stock Android. Memory is filled with essential apps only (including Google Play store). Notification drawer is adjusted to a DAP function and includes useful shortcuts (e.g. analogue/digital line out, gain level, USB connection type, digital filters). There’s also Pure Music mode which works as high-priority fullscreen application (enabling it doesn’t require a restart). Android settings offer basic options plus disabling the buttons when the DAP is locked.

Music player in Pure Music mode has been developed. Left flank of the app is filled with options like gapless, balance and gain adjustments etc. The app also includes ViPER Effect sound enhancements, most of which aren’t free. Home screen of the player is highly adjustable and features handy shortcuts. Music files can be launched via library or folders. I enjoyed Pure Music mode much and used it more frequently than PowerAmp.

One needs to remember that X5 III is not a smartphone and it has its limits. WiFi is not very fast and the same applies to FiiO’s OTA update servers – applying updates via microSD card is usually much quicker. The performance of internal memory and card slots is not very impressive too (in case of internal storage transfer rate is typically between 5 and 13,5 MB/s). Luckily, sound cracks do not appear and the overall performance is still decent for an audio player.

When using dynamic-driver IEMs hiss is not audible, but noticeable when using low-impedance and high-sensitivity Balanced Armature IEMs. Wi-Fi module doesn’t disrupt the sound and Bluetooth supports aptX.



● SoC: Rockchip RK3188 (4x1,4 GHz)
● RAM: 1 GB
● OS: Android 5.1.1 Lollipop ; Pure Music mode
● screen: 3,97 inch, IPS, touchscreen, 480x800 px
● DAC: 2x AKM4490, 32-bit/384 kHz
● LPF: 2x OPA1642
● OP: 2x OPA426
● USB DAC (24-bit/196kHz), Wi-Fi 802.11b/g/n (2,4 GHz), Bluetooth 4.0 aptX
● 32 GB internal storage, two microSD slots (up to 256 GB)
● 10-band equalizer, 120-step analogue volume control
● battery: 3300 mAh (up to 10 hours of life)
● balance control: +/- 10 dB
● 2 gain levels
● dimensions: 114,2 x 66,2 x 14,8 mm
● weight: 186 g


Cans: Audeze LCD-2 (Double Helix Fusion Complement4, PlusSound X8), MrSpeakers Ether 1.1 (Forza AudioWorks Noir HPC mk2, DUM), Final Sonorus III, AKG K612 Pro, Focal Spirit Professional, AKG K551, Noble Audio Savant i Noble 4, Etymotic ER-4PT, Brainwavz B200
AMPs + DAC/AMPs: Burson Conductor Virtuoso (Sabre), AIM SC808, ODAC i O2, Leckerton UHA-760, Zorloo ZuperDAC
DAPs: iBasso DX200, iBasso DX90
Interconnects: Forza AudioWorks Copper Series, Klotz
Music: various genres, different bitrates (including 24-bit), binaural tracks

X5 III surprised me with the sound quality and its signature. Applied DAC is known for warmer, mid-forward sound, while X5 III is neutral, bright and direct-sounding. FiiO’s sound signature, however, is still audible. X5 III resembles X7 1st gen, its smooth, a tad digital tuning, but the overall quality is a one step up. The sound is universal, detailed and surround. It allows for both analytical and relaxing listening. The signature has its flaws, though.

Bass is not dry, very hard and precise. It also doesn’t offer much attack and dynamics. Lows are vigorous and don’t get muddy and rumbling. It’s neither very fast nor very slow. It’s well-controlled – low tones are nicely separated from one another. The sound is not boring - when needed, a bass drum enters or midbass becomes stronger. Bass reveals many details, but not all of them. FiiO’s devices are often associated with emphasized midbass, but with X5 III the lows don’t overtake, are rather even, with appropriate transition into subbas. Bassheads won’t enjoy such signature, which is rather neutral and transparent. The sound is not thin, though – the bass is present, but not exaggerated.

Midrange is neutral and even. It’s not recessed and not forward either. This range is direct, clear and bright, not dominated by bass and not covered by trebles. Again, there’s no sign of harshness or dryness – the sound is smooth and pleasant, but without losing much resolution and details. Live instruments don’t impose, female vocals don’t hiss and the level of details isn’t overwhelming. The sound is fairly detailed, put somewhere between being analytical and musical. Lower midrange is not emphasised and not overlapped by bass. Midrange is close and non-aggressive. It works well with music genres featuring vocals and live instruments, but synthesizers and modern music also sound fine. Signature is not very natural, not warm. On the other hand, it may also not satisfy people seeking very analytical, highly-contoured tuning.

Upper midrange fluently turns into treble. This frequency range is solid, but – just as bass and midrange – also smooth and soft. It’s bright, but not syblilant. High tones seem a bit artificial, digital, but still at acceptable level – it’s more annoying in other FiiO devices and in two older generations of X5.

Holographics is impressive. One can actually hear that the device is using separate DACs for each side – channel separation is strong, the sound is airy with distinctly separated instruments. Soundstage size is optimal – it’s neither a hangar nor a concert hall. The device clearly exhibits instruments in all directions. The listener is plunged into music, but there’s no effect of discomfort, crampedness, aggressiveness. X5 III doesn’t sound distant – the user is placed in the middle of the scene, next to musicians.

Line out

Line out works awesome, which is in a way… disappointing. This is because when you add a better amplifier, you start to notice some vices of the chip that FiiO uses. When you pair X5 with such a great device as Leckerton Audio UHA760, it is then hard to return to the headphone output – the sound improves a lot. It remains smooth, but gains better dynamic and higher resolution. It seems that the internal amplifier makes the sound smoother. When using a line out, one can hear more details, soundstage also improves and bass is fuller and tighter.

On one hand, X5’s sound can be further improved by adding a high-quality external amplifier. On the other, if you find a decent combination, you may not want to use the headphone out anymore.

FiiO X5 III vs other DAPs

In its price range, the newest X5 is a very good sounding DAP. However, the sound quality is not as good as in Astell&Kern products. iBasso DX80 is also superior, not to mention the DX200. When using the line out, the differences are smaller, yet the FiiO device still loses. Naturally, X5 III offers a whole lot of features, but I wouldn’t call it a killer-DAP.

For me, X5 III performs on par with iBasso DX90 and Astell&Kern AK70. The first one offers harder, more raw and analytical tuning, which is not as easy to listen, but makes the sound more dynamic. X5’s tuning is more calm, less vigorous, but also speedy. FiiO’s device is smoother, musical, with better instrument separation and more air. If one prefers details, DX90 will be a better choice. X5 works better for neutrality in a musical version. Last but not least, one needs to remember that DX90 is much less feature-packed.

AK70’s tuning is more musical and coloured. The DAP offers more midbass and not as transparent and direct midrange. It sounds warmer and offers smaller soundstage, less air and worse separation.

iBasso DX200 provides much higher resolution and dynamics, bigger soundstage, deeper bass and trebles. By contrast, X5 is smoother, thinner, with softer tuning and lower dynamics and a smaller soundstage.

In case of Astell&Kern AK300, which utilizes the same DAC, but just a single one, the sound is more natural, but warmer. Midrange is closer and bass is more tight and massive, trebles are softer and the resolution is a bit higher.

FiiO X5 III vs headphones/earphones

X5 III pairs well with the majority of headphones and earphones, but not all. I much enjoyed it with Etymotic ER-4S and ER-4PT, which have become softer. FiiO works surprisingly great with AKG K551, but not as great with Focal Spirit Professional – the sound is too smooth. Noble Audio 4 hiss quite a lot, but in general sound good. X5 also pairs well with Noble Audio Savant and Brainwavz B200, so with both neutral and darker IEMs. I wouldn’t pair it with very bright and thin earphones/headphones. The device won’t add the lows or cut the highs.


FiiO X5 III is not a perfect device and not a killer of much more expensive DAPs. As a whole, it’s, however, an excellent piece of gear, which I enjoy a lot. I prefer it over FiiO X7 1st gen with a standard amplifier and it’s also much better than the previous generations of X5. 3rd gen X5 is perfectly-built, easy to use and packed with a lot of features. Android OS works fine and allows streaming and connecting Bluetooth devices. It’s a fantastic all-in-one device that also offers great line out sound.

Personally I think that the performance of internal storage and card readers as well as Wi-Fi transfers are not limiting. I wouldn’t call X5 III a cheap DAP, especially that its 3rd generation is more expensive than the previous two. For its price, new X5 is for sure worth recommending.

maciux - Maciej Sas