Review: Fiio M3 – Ultra Portable Audio


Some 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 soundstage, 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 I can’t measure it this time as I’d need to be able to isolate the signal from the M3, and I don’t have the equipment to do this – so instead I have shown Fiio’s graphed frequency response from a -5dB sinusoidal signal. This shows a pretty flat curve with slight roll-off below 50dB, and slight peak at around 16 kHz – but for all intents and purposes flat (peaks and roll off are less than 0.1 dB so at the extremes are essentially inaudible).

So instead, I’ll just say that I really like the sound from the M3, and will give you my (very) subjective impressions of the M3 compared to the X1 (as this will be probably the closest competitor and I don’t have anything else in the range to compare.

With this comparison, I used a 1 kHz test tone to exactly match volume, and used my Adel U6 to compare on tracks I know really well.

Warning – very subjective impressions ahead.

Fiio M3 vs Fiio X1

The first thing I noticed between the two DAPs is that the M3 seems to be very slightly warmer than my X1 (this was a trait repeated on both the X5ii and X3ii also). The second thing is that I think the X1 resolves small details slightly better. With this comments though, the difference is pretty small, and after volume matching, the only way you’d notice it is with critical listening, which is something most people won’t be doing when they are “out and about”. In terms of stage, bass, treble, mid-range – I’m not noticing a lot of difference – except for the fact that the X1 sounds slightly cleaner and clearer. What the M3 brings instead is a slightly smoother, more organic sound which some may really like, and others not.  If I had to highlight the difference I would say that the M3 would be the Classic 5th Gen iPod vs the X1 being the Classic 7th Gen iPod (organic vs cleaner / detailed sound).  I know a lot of people preferred the 5th Gen for the Wolfson DAC’s more organic sound – but I always like the 6th and 7th Gen for their cleaner more detailed sonics.

So on pure SQ alone, I’d probably lend my preference toward the X1 – but let’s see what changes when looking at some of the other features.

On size and true portability – no competition – the M3 wins easily, it is a fantastic little DAP to carry around, and whenever I am out and about now, it rarely leaves my trouser pockets. And ditto for battery life – the M3 just goes and goes, while the X1 is a little more limited (by around ½).

For the UI – I actually don’t mind either – but in terms of features within the UI, and the superior sorting and maturity, I’d take the X1 – and this is especially so when looking at things such as EQ. And the X1 also takes the crown for power, and also the ability to pair with an amp via line-out if required.

Finally – when looking at cost, the M3 is considerably cheaper, and for some this will be a big factor.  Actual value will be a different proposition and largely dependent on the individual features of each unit and your own preferences. For me personally – for an all-purpose DAP on a budget, I’d probably take the X1 – but for a truly portable rig, then the M3 is extremely compelling. And in fact most of the time when I am heading out and about now, I usually take the M3 + either the Adel U6 or new q-Jays (depending on my need for isolation).  And remember – I have the choice of M3, X1, X3ii, X5, X5ii, and a couple of top tier DAPs from L&P (the L5 Pro and LP5).  The reason is simple – it’s tiny, sounds good, easy to use, and will last all day.


I waited a while before completing this review – mainly to see how the firmware matured, and whilst it has definitely improved, it’s still not complete yet, and may not be for a while. This does not mean it is not usable yet, and for some (me included) I’d buy it anyway – it still brings a lot to the table.

The M3 is a tiny little DAP with reasonable storage options, great form factor, fantastic battery life, and some pretty good features.  It is also pretty cheap, and has a nice smooth slightly warm organic sound.  It is a wonderful choice if you are very mobile, or need a cheaper “run-about” for gym sessions etc. It has a low output impedance which is ideal for IEMs, and enough power to successfully drive most portable earphones or headphones.

Where the M3 lacks is with its very rudimentary GUI, limitations with tagged library, and quirky organisation.  Because of this, if you are a little “OCD” about everything being organised 100% and the GUI being completely intuitive and hassle free – then the M3 is not for you.

For those who are willing to make allowances though, I would thoroughly recommend it. My 12 yo daughter borrowed it for a few hours, and even in that short time she was using it like a pro, and was thoroughly delighted with the interface. For me personally, the M3 has become my default DAP for exercise or outdoor activities.

On a star rating, I’d give the M3 somewhere between 60-70%, which in my books is pretty good.  If Fiio can smooth out some the wrinkles, then I can see the M3 becoming a classic over time.


My thanks and appreciation to the team at Fiio for this opportunity, and as always to Lieven for the opportunity to post on Headfonia.

3.7/5 - (98 votes)


Paul is a Kiwi from Down Under (New Zealand) and spends his time selling Lamb by day, and playing round with audio gear by night. He's a self confessed music junkie, with wide musical tastes and a penchant for female vocalists. He is not a golden eared listener, prefers to review armed with an SPL meter and objective measurements, and does his best to balance objectivity and subjectivity. Mostly though, he can be found with headphones on his head, and a smile on his face - lost in the moment.


  • Reply January 12, 2016


    Excellent review, written perfectly for this product. My recent experience with FiiO’s K1 amp shows that they make amazing tiny audio products.

    • Reply January 13, 2016


      Thanks Dale. I have the K1 with me too, and you are right – quite extraordinary the SQ which can be achieved with such a small footprint.

    • Reply February 1, 2016

      Miroslav Klima

      Dale, can you please share your experience with K1? I have Yamaha HPH MT220 (VERY happy with – thanx for you review) and looking for affordable DAC/amp. I know pros/cons of K1 (android issue) and I am eager to know your sonical experience. K1 price/performance ratio seems to me very good…

      • Reply February 1, 2016


        I’m still using it. I just did a “reality check” comparing it to the FiiO E17k, using the iPhone 6s-plus and the new CCK adapter cable. While the K1 definitely improves the iPhone’s bass detail, and is marginally smoother elsewhere, the E17k has more impact and “air”. I don’t think most people would notice without a direct comparison, although if you really pay attention, you might get that sense after a long time listening. I think the K1 is worth buying and using, but to be honest, if you can spend more, I would.

        • Reply February 2, 2016

          Miroslav Klima

          thank you very much, I definitely can spend more, if it makes sense to me

    • Reply May 22, 2016

      Alex M

      I’m a bit confused. I have a player – iPod nano 7 / android phone (currently nexus 5x). Do I need another player like this one or should I buy an amp, like Fiio K1? Or should I buy Fiio M3 AND an amp? Does M3 serve as an amp?

      Reason to buy an amp for me – not to have more volume (with all my current headphones it is fine); it is rather to improve the clarity and overall listening experience.

      About me: I’m not planning to invest into “monitoring” headphones, however I’m starting to be not satisfied with mp3 quality (even 320) with relatively good over-ear headphones. So I’m looking for 2 things – portable solution “on the go”, preferably that will also work with a laptop. Great if it can be one device. And I’m not planning to ever move from 16bit. My ears told me that they prefer 16 over 24, since 24 bit “adds noise” that overweights the benefit of a “more spacious” sound.

      • Reply May 22, 2016


        This could be something that takes time to figure out. At the start, if you could be OK with adding an amp to your phone or iPod, then you could buy something like the Oppo HA-2 (or similar), and be done with that part of your search. Because if you change devices, the Oppo would very likely work with whatever you switch to. But there are DAPs that outperform the Oppo that could give you great sound and all in one device, without the external amp. Myself, when I’m actually outdoors, I don’t need greater clarity than iPhone or iPod, because of outdoor noise levels. So I only have a concern for indoor listening.

  • Reply January 13, 2016

    Narbiyan Tedyanto

    Nice review as always. How you compare m3 vs x3 1st gen? In terms of portability and SQ.

    • Reply January 13, 2016

      ohm image

      They aren’t on the same page. The X3 first gen has a better output, capable of surpassing 16-bit in most metrics. The M3 both hisses more and can’t surpass 16-bit. But the M3 is WAY easier to use. Personally, if it hissed less, I’d be down for it over the X3 Gen 1.

    • Reply January 13, 2016


      Unfortunately the original X3 is one of the few Fiio DAPs I never had the pleasure of trying. In terms of portability though, the M3 is the smallest Digital Audio Player Fiio has released to date.

  • Reply January 13, 2016


    I just got my M3 less than an hour ago. I have read that it is tiny, but not this tiny compared to my X3 1st gen., X3II and X1.

    Sound-wise, with my Ortofon EQ-5, I find it refreshingly clear and clean compared to the darker X3 1st gen. My subjective ears, old pair at 55 years of usage, take it to be closer to X3II’s sound signature than my X1 with the same music tracks I normally listen to.

    I had more than a few “toyish” looking and feeling DAPs through the years. Sandisk’s Clip+, Express, e130 and a couple of Creative players. The “heftier” ones were an iTouch 5th and a Fuze.

    For its sound quality, size and weight – the M3 is a good buy for those who simply like to carry a very light and “straight music player.”

  • Reply January 16, 2016


    How does it compare to sandisk sansa clip plus?

    • Reply January 17, 2016


      Sorry – I haven’t had a chance to try the Sansa.

    • Reply February 26, 2016


      The Fiio M3 are more clean, neutral to bright, and a bit more detailed and textured but all of this is just in comparison to the Sansa Clip+ Rockbox. A sansa have thick notes, with more body and with an effect producing a fine but fake-flat-soundstage, relativity wide and put in front, but not as deep, aired, with clear instrument separation and layered in comparison with M3, I think thats the way to produce a more realistic and coherent soundstage. Anyway, the Sansa are a very very good player, sounds very good, this are very tiny differences, so for the price, maybe take both if you can. Or go for the X1 (more prominent player in general) and keep the Sansa.

      I used a RE400 for this, neutrals and very well balanced iems.

      (Not native english, I apology if you can’t understand something what I wrote).


  • Reply January 18, 2016


    One thing I wish is perhaps connectivity to Portable DAC through the USB Micro Port. You forgot one feature that it is compatible with In-Line Wired Control from the headphone cable. Skip, Pause Play doesn’t need to reach your pocket. Very handy.

  • Reply January 18, 2016


    Thanks for this excellent, detailed and well written review. It is very useful. I own a X1 and I’m so happy with it. I can’t believe that Fiio could make a tinier DAP. I’ve been trying to convince my friends to drop their cell phones to listen to music and the 100 dollars X1’s price tag seemed a extremely cheap option. And the M3 is such a great surprise. Those people who love music and their ears should buy this.
    Thanks again!

  • Reply February 8, 2016

    Ed Weisz

    Though they are on a different price bracket, how is the audio quality of M3 vs X5 II? I’m currently using Fidue A83 and looking for an upgrade for better/improved audio experience.
    Listening on the same music on my PC vs. my long time audio player (Rockbox-ed) Sansa Clip Zip. To me, my PC sounds warmer (which I like) while the Clip Zip is on the brighter side.

  • Reply March 17, 2016


    Which one would you recommend among fiio m3,fiio x1,xduoo x2,xduoo x3?

  • Reply April 18, 2016


    fiio m3 or Onn X5 ?

  • Reply April 19, 2016

    Francisco Urteaga

    I´m a runner. I see that portability is no issue, my worry is mainly that, with all the movement it might skip songs or freeze, would this be a problem?

    • Reply April 20, 2016


      Not sure what you mean. There should not be any loose parts, unless the control on your headphone cord has an electrical short and causes those problems.

    • Reply October 12, 2016


      The only MP3 players that you would have to worry about skipping or freezing are hard drive style players like the original iPod’s and iPod Classics with the huge amount of storage. Those should not be taken running or anything that involves bumps and shakes because not only will the music skip, you run the risk of destroying the drive inside.

  • Reply May 27, 2016

    Jack Thompson

    The only place i really get to listen to music these days is when im driving in my car. I had an old sony nzw-e354 which i plugged into an aux input on the car stereo. The sony recently died on me.. So would this be an affordable alternative?

    • Reply June 21, 2016


      I think it should be an affordable alternative (I say that for what I’ve been reading these days). I do not own this device, but for such a price, maybe you should go on. Plus I want to give it a try (I’m just waiting to collect all the money).

  • Reply November 20, 2016


    Hello, sorry my English is not that good I guess, so I try to make it simple. Can I use something like AKG Q460 or Sennheiser HD239 with M3 or it’s better to use an earphone?!

  • Reply December 14, 2016


    Hi Paul.
    You mentioned you got a 128gb SD card to work on the M3 despite the imposed 64gb limitation.
    I own the M3 is there anything specific I should do to get an SD of 128gig or beyond to work ?
    Format it in a certain way internally or on pc (FAT32, ExFAT, MTFS) ?

    Thanks in advance

  • Reply January 24, 2017


    Thanks for the review. The file sorting thing and the drive-sort hint brought me to the Linux version, and an apt install fatsort later the play order was corrected. This was just the tiny bit of information I needed. For all those stumbling over my comment and using Linux: You’ll have to apply fsck.vfat first eventually before using fatsort.

    HTH, ändu

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