FiiO M15S Review


UI & Usage

Android 10.0

While the old FiiO M11 / M11 pro and M15, ran on Android 7.0, the new M15S – like the M11 Plus ESS and M11S is fuelled by the 10th version of the popular OS.

Thanks to that, the player sports various optimizations like dark mode, gestures, and most of all, a full Google Play Store experience. This means you can install all third-party apps, like Qobuz, Tidal, and… Apple Music, which became my main service, thanks to low price, good pay-out for the artist, and most of all true Hi-Res streaming!


Of course, if you prefer to use FiiO’s own market, you can and the app is still pre-installed for those who don’t want to create a Google account. And thanks to the faster CPU + Wi-Fi chips, download speed is still on par with its bigger siblings, and just a bit slower than iBasso’s flagship, the top-dog in this aspect – A&K being at the bottom by comparison…. A very good experience overall!

Compared to the previous generation (M15), the difference is quite impressive with faster boot-up speed, quicker firmware upgrade, better app compatibility, and other little caveats, now gone. To sum it up: a better UI and a better experience, night and day on a daily basis.

Overall navigation

The FiiO M15S gives you the same exact same navigation menu as seen on the M11S and M17, no more, no less. Which is a good thing as the brand really outperformed a lot of players on this point, delivering constant software updates via OTA.

What’s interesting however is how snappier the whole player appears, compared to the “old” M11 / M11 Pro / M15. The new CPU and new UI really edge the previous generation in terms of speed, smoothing out every action as when you download some tracks, try new apps or navigate through those same apps.

All in all, it’s one of the best experiences available at the moment, but I expected no less.


Streaming / DNLA / FiiO Link

Now that every FiiO was gifted with a Google Play Store certification, all it takes is a Wi-Fi connection, and you can directly install all the apps you need. As I said, I’m a big fan of Apple Music, but Qobuz, Tidal, Spotify and Deezer worked well too, just remember to pick the highest subscription you can, to fully enjoy hi-res streaming.

FiiO Link is also available: with Bluetooth pairing, you can control your player directly through your phone. It works well and somehow gives the same seamless experience as the Hiby link on Hiby and Cayin players, or the new Variations V6 that I previously reviewed. The only catch is that it’s only available for Android, and that will remain the same as it seems.

FiiO still supports AirPlay with its player, but unlike the first generation of M11/M15, the dedicated AirPlay button isn’t directly shown in the upper menu anymore. To access AirPlay mode, you know have to:

  • slide your finger from top to bottom
  • Click on “Mode Choose”
  • and THEN you’ll have the new AirPlay mode available !

Once activated, and if you have Apple devices hooked on the same network, you’ll then be able to stream your music directly to the M11S, up to 16bit/48kHz – so better than Bluetooth, but worse than direct access to your HD streaming service.

DNLA works the same way, and you can even access your distant drives from the FiiO Music app or apps like Bubble UpNp. Or any compatible app, like HiBy music or Audio Player Pro.


FiiO Music

Sure you can use any android music player app you want, but the FiiO Music app is now very, if not the most, competent solution available for the player, and matches the FiiO M15S perfectly well. It’s fast, reliable, easy to use, and remains one of the best player apps out there. iBasso is (very) close, but I still prefer FiiO which offers more frequent updates.

From there, you can :

  • scan your SD-card or the internal storage, to access all your music, neatly sorted in album/artist/genre/folder
  • access your NAS and use the FiiO M15S as a network player
  • transfer files from your player to your computer/smartphone wirelessly
  • change the equalizer and roll-off filters

On a daily basis, there’s really little to complain about and FiiO feels so confident about its in-house player that you can also put the player in full DAP mode, restricting the M15S to local files only.



Battery Life and Charging

To the question: why so thick? The answer will always be: batter. And, like the M11S, the FiiO M15S embarks an ultra-high capacity lithium cobalt oxide battery sporting no less than… 6200mAh!

With a battery this big, you’d expect 15h of continuous play, but unfortunately FiiO announces a 9h to 10.5 duration – almost 2h less than the previous model. To make for, the M15S now comes with QC3.0 and USB-PD compatibility for fast charging, but whatever the case, this is a player that you’ll have to charge more than often.

Nonetheless, during my tests, I’ve almost always reached the 10h threshold, even with Wi-Fi and Bluetooth enabled, but I stayed in mid-gain most of the time, which might help.


USB-C and SD Card

As expected, the FiiO M15S gets an USB Type-C port, an all-in-one plug with a reversible design, fast data transfer, and Quick-charge to fill the massive battery.

Again the USB port works both as an entry and a gateway: you can either plug the M15S into your computer and use it as a DAC or connect a DAC and use the player as a source. A cool option that seems to be available on more and more on DAPs, and one I use much more than I expected with my actual setup.

But the big news is the USB 3.0 support, a game-changer feature when you have to copy/remove some music from your player, saving you the hassle of buying a micro-SD car reader.

About that, to my dismay, the M15S kept the sim-tray system for the micro-SD card… Classy, but not very handy.


Everyday carry

Bigger than ever, the FiiO M15S is also thick(er) and heavier, giving me mixed feelings on the go.

To be fair, compared to the OG M15, it’s only thicker by a mere 2-3mm, but it’s also a tad heavier: 345g on the scale, without the case! And if that doesn’t look like much on paper, combined with the thickness, it gives a false sense of heaviness.

It’s a fatty smartphone or one with a big battery attached, and if It’s not impossible to carry – especially compared to the FiiO M17 – but I would be lying if I said it’s an easy player to carry, even compared to my phone, longer but thinner. On the other hand, the volume controller has been vastly improved, and honestly, this is one of the smoothest wheel I tried across every DAP out there. To lower/increase the volume, you can also click up and down with the buttons on the side. It’s simple, accurate, and can be a good options for fine-tuning your volume level. It’s a gimmick, but a cool one!

Last but not least, there are the new convex-shaped buttons. I found them pretty cool to look at and handle, especially when you use the leather pouch. Add to that the option to configure the “shortcut” button with extensive options like ‘filters, playback modes, USB DAC / Media Storage” and it’s almost fool proof.

To push things even further, I paired the player with the Astell&Kern PA10, with the 4.4mm Line Output. Clearly, you’d be dumb to use that combo on the go, but on the train, it’s something that I could consider…


The article continues on Page Three, after the click here

Page 1: about FiiO

Page 2: UI, Usage, Bundle

Page 3: Technical specifications

Page 4: Sound performance

4.6/5 - (34 votes)

A nerdy guy with a passion for audio and gadgets, he likes to combine his DAC and his swiss knife. Even after more than 10 years of experience, Nanotechnos still collects all gear he gets, even his first MPMAN MP3 player. He likes spreadsheets, technical specs and all this amazing(ly boring) numbers. But most of all, he loves music: electro, classical, dubstep, Debussy : the daily playlist.


  • Reply April 29, 2023

    William Aitchison

    Hi….many thanks for this superb review, I have a FiiO M15S (previous was an M11 ESS) and this M15S is MUCH better and I agree with every word of the review….I waited ages for this Mark II M15 and I am not disappointed….
    Interestingly I also have the A & K PA10 and agree with the reviewer, it lifts the audio quality to another level…..a word of caution though, I found using the A &K supplied unbalanced jumper cable not that good but going to a 4.4mm to 4.4mm balanced connector ( as shown in the review) made a substantial difference the the sound quality and I’m surprised A & K did not include one considering the cost ay the PA10 and the very modest cost of the jumper cable.
    That said, the FiiO M15S is the best FiiO I’ve had yet (and I’ve had a few!) and once again thank you for a great review.
    Happy listening!!

  • Reply May 1, 2023

    Gregory David

    Thanks for the review! Question, I would like to use the M15s as a transport from 3.5 mm to COAX, not the USB. Did you try out this function?



  • Reply May 16, 2023


    what is up with all these black and white photos? You really cant get a good feel or look at the player doing that.

  • Reply June 12, 2023


    Would love to hear thoughts on how it compares to the ibasso dx240.

  • Reply December 10, 2023


    This is a fair review but it misses the main feature (except for a dismissive passing reference). This is the provision of additional gain levels when the DAP is plugged into a fast charger. The super and ultra high levels for over-the-ear cans make a transformative difference in precision, clarity, tonality and staging. You don’t have to listen with a high volume setting to get the benefit. I had been getting a bit disappointed with the M15S and Hifiman Arya combination until I “discovered” this hidden feature, after deciding to by a fast charger (£10). It unlocked the qualities of both. Of course, this is not a portable mode, but it is outstandingly good. You don’t get any of it without the mains electricity. Hence this tepid review.

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