FiiO is the company behind many very well regarded DAPs. The FiiO X7 hits the higher end DAP segment while the M3K covers the budget segment. Most importantly, they all give the audio quality and listening experience that audiophiles want for reasonable prices. Today, we review a midrange offering (299USD) with streaming support and a sleek, modern design in the FiiO M9.


2.Packaging & Accessories
4.User Interface and Operation
5.Battery Life


Processor1GHz Exynos 7270 14nm
DACAK4490EN × 2
Screen3.2″ 480×800 LG IPS Touchscreen
File Format SupportMP3,OGG,WMA,AAC
APE(Fast): 192 kHz/24 bit
APE(Normal): 192 kHz/24 bit
APE (High): 192kHz/24 bit
APE (Extra High): 48kHz/24 bit
APE (Insane): 48kHz/24 bit
FLAC: 192 kHz/24 bit
WAV: 192 kHz/64 bit
Aiff:192 kHz/24 bit
Aif:192 kHz/24 bit
WMA Lossless: 96 kHz/24 bit
Apple Lossless: 192 kHz/24 bit
Storage4GB, with 2GB available to user
Storage ExpansionMicroSD up to 2TB
Connectivity 2.4G WiFi, Bluetooth 4.2 LDAC/aptX/aptX HD/SBC (Available when playing on M9 or using M9 as USB DAC), Airplay, FiiO Link, DLNA, USB 2.0 Type C
Battery 2350mAh Li-polymer battery
Around 15hours playback, 45 days deep sleep
Power Output ≥125mW (16Ω / THD+N<1%)
Output Impedance <2Ω
Frequency Response 5Hz~80 kHz (-3dB)
THD + N <0.002% (1kHz/10kΩ)
Noise Floor ≥117dB (A-weighted)
Recommended Drive Loads 16~300Ω

As with most of our DAP reviews, you can find the comprehensive list of specs at the official FiiO site here – we’ve condensed it down the most commonly searched for / important stats for our review.

Packaging & Accessories

The FiiO M9 comes in a no frills cardboard packaging box that’s really just meant to hold the bare minimum. To be fair, that’s actually a good thing – we should all try to create less waste. The box comes with just enough space to safely store the device, and another smaller box with a USB-C cable provided. Like in the FiiO M3K, FiiO has helpfully included a soft plastic case for the device, as well as a glass screen protector.

I only discovered this when I noticed there was a crack on my screen. Horrified by my carelessness, I took a closer look to see if there might be a screen protector, and luckily for me, there was! So rest assured that your M9 will come with a decent level of protection right out of the box.


The FiiO M9 is a gorgeous, medium sized DAP. With its X” screen and rounded edge on the left side, and an aluminium housing, it sits neatly and comfortably in my average sized hand (I’m around 5’7″ for reference). There are no obvious seams in its design – it looks like it is probably milled out of a single piece of aluminium, giving it quite a premium feeling even at its midrange price point. All the operational buttons sit on the left side. Starting from the top is Power, Volume wheel, Play/Pause, to Next & Previous Track at the bottom.

The part that stands out the most is the gold coloured volume control wheel. Nestled inside a curved indent on the edge of the device, the wheel has a gently ridged texture to it for added grip. Spinning it is a perfectly smooth experience, with just the smallest of clicks to register each change in volume level. I would have liked a bit more resistance when spinning to help with the control, but that’s just my personal preference.

On the bottom of the device, just under the screen is an LED-backed FiiO logo which lights up during playback. The colour of the light will change depending on the file format – 96kHz 24bit FLAC will activate a green light, 44kHz 16 bit FLAC gives a purple light, and MP3 is blue, for example. Not the most useful feature, perhaps, but I find that it does add to the experience as you can quickly know that there is a file format change without having to open the file details in the FiiO Music app. The brightness level can also be adjusted in the phone’s settings; I like to keep things dim to save battery.

Moving back to the overall design – I really only have praise for this device. I find that its design is spot on as to the kind of device I would like to use. The FiiO M9 hits a balance between premium design at a budget, midrange price point, pleasing for the wallet conscious user with high standards. Though small, the 3.2″ IPS LCD screen is quite sharp and bright, although colour reproduction seems just a little desaturated.

The microSD card slot lays on the left edge of the device, neatly placed under the volume rocker. The 3.5mm and 2.5mm jacks are placed on the bottom face of the device, elegantly highlighted with gold metallic rings around each. Plugging in to the audio jacks feels extremely secure, with a good amount of resistance to ensure that your headphones won’t easily come flying loose. Finally, the device comes with a USB-C port on the bottom as well.

User Interface and Operation

Like many DAPs these days, the FiiO M9’s OS is based on Android. When I say based on, it’s because FiiO has heavily customized their version to have a gesture based control which is very straightforward – swipe up from the bottom left to go back a screen, and swipe up from the bottom right to go right back to the homescreen.

Additionally, FiiO has completely removed all signs of Google Play functionality, so you won’t be able to simply login to your Google Account, open up the Play Store and download your favourite music streaming apps. Instead, you’ll have to sideload the .APK file of the music streaming app from your computer onto the FiiO M9, and then install it that way. FiiO has also restricted the apps that can be installed onto the device this way through an app whitelist. While it is a little more annoying just to get Tidal or Spotify on the device, my guess is that this is probably to avoid having to deal with license fees for Google Apps, and also prevents users that aren’t as tech savvy from installing malware onto the device that may the experience.

One negative about this customized Android experience is that FiiO decided to even remove the basic web browser app. What this means is that it is impossible to sign to WiFi on networks where an extra confirmation step is needed in order to connect to the network. I hope that they can bring back web browser functionality in some form in order to expand this great device’s connectivity capabilities.

Operating the M9 is honestly not the smoothest experience – with only 768MB of RAM and a processor from 2016, don’t expect the kind of smooth interface that smartphones have. Loading Spotify will take longer than usual, and switching between the tabs in the app will cause the device to stutter a little bit. Once everything gets loaded and settled down, the playback experience is still smooth. On the other hand, the FiiO Music app seems to be optimized for the device and runs pretty lag free in comparison, so if you will have a smoother experience if you only listen to music locally. Finally, due to the heavily skinned Android experience and the small amount of RAM, you can only really run one app at a time – opening a music app will close any other music app you might have open.

Another small problem with the FiiO M9 is that though the screen is sharp and large enough to comfortably view things, it’s not quite large enough to display a comfortably sized on screen keyboard. When searching for tracks on Spotify, I find myself having to maneuver very carefully between the keys and with the added occasional lag, it becomes a little bit troublesome at times.

Regardless of the small flaws, FiiO has included a good set of audio related features. There’s all the basics like low and high gain, digital filter mode (though I haven’t found it to affect the sound much), balance, max and fixed volume settings. My favourite feature is the ability to disable certain buttons when the screen is turned off so that you can prevent accidentally changing the volume by disabling the volume wheel, while keeping the play/pause button toggle-able for example.

If you can overlook the minor software flaws, the FiiO M9 is an impressive and affordable DAP and offers a positive user experience for high quality audio playback.

Battery Life

The FiiO M9 has pretty average battery life, able to last throughout my typical 5 day work week commute (around 3 hours a day), but I pretty much had to recharge it by the end of this interval. Throughout my testing, the Screen Brightness was set to around 40% brightness, Volume usually between 65-80, on Low Gain. I typically tested it with the built in FiiO Music app as well as Spotify.

One glaring flaw was that when the WiFi was turned on, even if it was not connected to a network or streaming any music, it would drain the battery at probably double the normal standby rate. This was a source of disappointment at the beginning when I did not realize this was an issue and picked up a nearly drained player as I was about to go out, so make sure to turn off the WiFi if you are not using it. Make sure to set a auto shutdown timer to make sure this doesn’t happen – this greatly improved my experience once I noticed it.

However, the M9 does charge quite quickly – I didn’t get a chance to time it, but it would usually hit nearly 100% within 2 hours, so it does make up for the fact that its battery doesn’t have a massive capacity and usage time.


Consistent with my experience with other FiiO devices so far, the sound is always quite neutral to my ears – my reference points being my OnePlus X smartphone and my iPad Pro, which both decidedly sound warmer than the M9 overall. I did my testing with the Oriolus Mk2, FiiO FH5, Tin Audio T2, and the FiiO F5. The M9 seems to have quite a flat frequency response – in comparison to my other devices like the iPad, it is less warm in the bass for sure. Bass impact sounds more reserved and cleaner with a slight emphasis on mid-bass rather than deep, warm rumble, but overall, soundstage and separation are a little better in return. I also find myself being able to focus on higher frequency details a little better when using the FiiO M9. While some users may find it a little cold sounding, I do enjoy the more neutral audio reproduction which can help bring out the finer details and provides a change to my usual listening setup. The clean audio reproduction, free of distortion, also helps to accentuate the soundstage width and also ensures that there aren’t any frequencies that sound especially harsh. So, if you have an IEM which sounds a little too boomy on the low frequency, you might find that the M9 is a good pairing for it to tame things down a little bit.

3.5mm vs 2.5mm Balanced

If you look at the technical specifications on FiiO’s site, there are actually some subtle differences between the 3.5mm and 2.5mm balanced output. Looking at the distortion curves, it seems that there is slightly less distortion from the 2.5mm side, which is good for the highly discerning audiophile. Additionally, the separation value is >98dB in the 2.5mm versus only >72dB in from the 3.5mm – which should mean better sense of soundstage from the 2.5mm output. However, the SNR from the 3.5mm is slightly better, coming in at >118dB over the >113dB from the 2.5mm.

Through my own testing with the FiiO F5, I did find the 2.5mm output seemed to sound very slightly more open, with the bass a little more clean – but I honestly would find it difficult to discern between the two in a blind test. Nonetheless, knowing that many users swear by 2.5mm output, the fact that this midrange product offers the option makes it an even better purchase.


While I do not actually use many of the Bluetooth, Airplay, or DLNA functions, modern connectivity options is what this device is all about so they definitely deserve mentioning. My experience with WiFi has certainly been stable and works well – with the only problem being that it doesn’t have a browser to connect to networks that require an extra step before authentication as I have already mentioned. I tested its Bluetooth function and it paired with other devices with ease. One nifty feature about the FiiO M9 is its ability to act as a Bluetooth receiver; this lets you stream audio from another device and take advantage of the M9’s amplifier and soundcard.

Another feature is the use of FiiOLink – an app that you can get on your phone in order to control the FiiO Music app on your M9 remotely. This can be a way to bypass the slightly laggy interface on the M9 and choose music from your phone instead. DLNA functions also allow you to stream music from the device on your local network as well. All in all, this device is just great for

USB DAC Functionality

Like many of FiiO’s other DAPs, the M9 can be used as a USB DAC – just download and install FiiO’s USB driver software from their site, plug in your DAP to the computer, and enjoy audio output from the M9 instead of your normal soundcard.


The FiiO M9 brings a lot of modern functionality into an affordable and sleek design. Going for just 299USD, it hits the spot for an audiophile like myself who wants to find an affordable option that performs well, looks good, and also has a modern interface with streaming service and other connectivity options. Yes, it doesn’t have the largest built-in storage capacity, RAM, or smoothest interface, but these are things I am willing to compromise on for the great build quality, design, listening experience, functionality, and most importantly, price.