The FiiO M3K brings to mind my first mp3 player. It was about the same size, though it lacked any kind of display much less a GUI, and it fitted a 10Mb SD card (rather than a micro SD card) and it was called an mp3 player because it couldn't play anything else mostly because a single wav file would be larger than its available storage. Things have come a long way since that first player, but some things haven't changed, the M3K is still tiny, a little over three and a half inches long and one and three quarters wide and about half an inch thick, and it still uses a memory card for storage, albeit quite a bit smaller in size and quite a bit larger in storage capacity, up to 2TB should they become available. But there the similarity ends, the FiiO M3K employs an Ingenic X1000E processor and an AK3476A DAC capable of playing up to 32-bit/384kHz PCM files, as well as DSD, CUE and LRC, and in a truly unique move it can also record via an incorporated microphone; the M3K will also operate as an asynchronous USB DAC and supports USB OTG, and of course the M3K has a full GUI, with half of its face dedicated to a 2.0 inch IPS display and the other half capacitive touchscreen controls.
The FiiO M3K
Though the Quads required 3/4 volume the 1Mores were happy with 2/3rds. The combination of the FiiO M3K and the 1Mores had great synergy as evidenced by Stan Ridgway's "Camouflage" (The Big Heat in 16/44.1 kHz), the rich bass and snappy highs of the 80's electro-pop tune enhanced without harshness or veiling of clarity. The soundstage was presented with medium club's sense of space.
For a look into orchestral performance I chose "Think of Me" from The Phantom of the Opera: Original Motion Picture Soundtrack (DSD). Though the vocals were a bit intimate the orchestra was large enough if a little heavy on the bottom end. Selecting the FiiO F9 PRO IEMs I cued up "Marlene on the Wall" (Suzanne Vega 16-bit/44.1kHz) and was treated to a surprisingly large soundstage and excellent tonal balance with Suzanne's voice very natural and realistic. Again, though a little lighter on the bottom end, there was none of the abrasive brightness usually associated with cheap amplifiers and cell phones.
Not having an OTG cable, I connected the M3K to my computer instead using the USB DAC function and put on "Everybody Loves Somebody" as performed by Dean Martin (Everybody Loves Somebody in 24-bit/96kHz). The soundstage was large dinner theater. And just to check the resolution of the M3K I switched between the 44.1kHz version and the 96kHz version and there was definitely a difference with the 96kHz coming out smoother more musical with a slight improvement to soundstage and instrument placement.
My next step was to test the recording capabilities. It took a little experimentation, but the recording function is pretty straight forward though you probably want to set the screen timeout to "On" if you are going to be recording as the controls lock when the display goes off. Though there is a small hole in the silicone skin for the microphone it does not appear to be particularly directional. To get a read on sound quality I took the M3K out to my living room and set it on the piano and played a few tunes. The sound quality was surprisingly good, certainly good enough for the occasional memo for which it is intended or even to capture the odd local band at the pub.
A little about the UI, it is very intuitive, I never needed to consult the owner's manual except to find where the microphone was, but just about anything can be found via experimentation. There is a menu that is only accessible while a file is playing and you need to exit the record menu twice, first time stops the recording, and second time saves the recording. Turning off the "Lockscreen Clock" prevents you from having to press the "Wake" button twice. The EQ is preset only, but is accessible on the fly by tapping the Menu button while a track is playing. The other on the Fly functions are "Add to Favorites", "Add to Playlist", "View Track Info", and "Delete file".
The Sum Total
The sound quality is very good, though not necessarily audiophile grade, it is able to drive full sized headphones and is very musical providing superior sound to most smart phones and many DAPs I have heard, and does so in a very convenient package that'll easily slip into your pocket. It has the best battery life of any portable player I have auditioned, including smart phones, and has one of the most intelligent GUIs to boot. Highly recommended for first time users.