Aune M2 32BIT DSD portable music player

 
 
Intro :
Since the past few years I had kept myself away from trying out any new DAPs or audio gear since I was pretty satisfied with my Fiio X5 (1^st gen) and Sansa Clip /Cowon D2+ that I had been using and secondly it kept my wallet happier.The X5’s jog wheel conked off long time ago and I had stopped using it so a new DAP is definitely on my mind now. That’s when my friend @toxicdrift informed about all these new DAPs (Shozy Alien Gold,Aune M2 Pro and Opus #1 ) he had just bought and offered to loan them out to me for testing .Just few weeks back I had posted the Bit Opus #1 review and  today I will be reviewing something from one of my favorite VFM brands – Aune (having tried their B1 amp earlier I’ve already been in love with their no-nonsense design and sound quality). Here’s my review for their mid tier version of the high end M2 dap series of M2 -  The Aune M2 Pro. 
 
I will be adding extended comparisons with other players once I’ve spent enough time with all of them and done some comparisons.
 
Packaging and Design : 
 
 
The M2 Pro comes in simple dark black cardboard box, pretty much like the one of their B1 amps. Since the model I was trying out was a M2 Pro it comes in silver (also available in black I guess). The Blue model which is reserved for more expensive and flagship model M2S looks very unique IMO and my personal favorite.
 


 
The additions in the box are the warranty card, Usb charging cable and a manual.  A basic case and some screen protectors etc could be great,  atleast a silicon or protective case needs to be the standard accessory for all high end players in this price range along with the option to purchase  a leather or better cases.
 

 
In terms of design is extremely bold yet understated with that straight lines inspired industrial look and a body which is clean solid piece of aluminum chassis with no visible joints or gaps . The brushed metal matte texture finish and laser engraved text give the unit a very premium feel when you look at it or hold it in your hands.
 


 
The front panel has the 2.4” IPS LCD screen and the Aune logo engraved above the screen . At the bottom 32 Bit DSD player is etched. The logo and other engraving doesn’t stand out much in the silver colour player as compared to the black and blue versions (M2S).
 

 
In the lower half there are 3 simple buttons for Back-Play and Pause (Select in Menu)- and Forward. The buttons are pretty solid and have good feedback. I could easily operate them without having too look at the player.
 
 


 
 
The back of the player has the branding , model number , serial number and assembly details etc in English as well as some Chinese text.
 
The top side of the player has the power button on the left , a long press is for turning the player on and off whereas a normal short press toggles the screen on/off when using the player.
 
The bottom side  has the 3.5mm headphone out ,  a line out (3.5mm) and the charging + sync port in the form of micro USB .
 
On the right hand side we have a small pin hole for reset function (using a pin or paperclip) , micro SD slot which supports upto 128 GB and a jog dial wheel for controlling the volume as well as back and fast-forward function when screen is locked. The wheel has a nice pattern texture which provides for better control and grip . There’s  a multi-function port as well covered with rubber protection .* not sure about its functions currently but I guess Aune plans to add extra functionality in the future using this port*.
 
Sound Quality :
 
Out of the box trying out the M2 pro  I was very impressed by the sound quality .Coming from a Fiio X5 , there was a good amount of difference in detailing and texture as well as background noise which was easily noticeable. I could say a good 25-30% of upgrade from what I was used to in terms of portability. The overall sound is lot cleaner and and revealing whereas the sound signature is a lot more balanced and neutral in comparison. The black backgrounds was one of the most impressive sound improvement that I noticed instantly.
 
Using the Sennheiser IE80s  , I had a smile on my face from the improved bass I was hearing . The speed and control was better, better texture and layering in bass . Perfect slam and reverb along with micro-detailing in some bass tracks which were not easily audible before. The IE80 no more sounded like a mid bassy IEMs which it does with many other DAPs even at the lowest bass setting.
 Even when using the Sennheiser HD598 which doesn’t have a very good sub bass , the overall output in the lower spectrum was a lot more controlled and clean .
 
The midrange is again extremely detailed and clear with good layering and no sign of any sibilance . Didn’t find any forwardness or warmth in the mid presentation nor does it sound recessed. I would say pretty much neutral , a tad bit of warmth might make it more fun sounding but it doesn’t sound dry or boring at all .Pretty much hits the right spot in terms of being perfectly neutral and not boring.
Listening to vocals tracks is pure bliss , very accurate representation and texture when listening to female vocals . Even the male vocals sound pretty good.In comparison the Opus #1 is slightly more warm /fun even though it maintains a neutral signature as well.
 
The highs are extremely detailed without being sharp or piercing. Again good amount of micro-detailing and clarity which shines through in the highs.
 
The soundstage is by far one of the best Ive heard in the below 500-600$ range. The soundstage and imaging along with the detailing almost makes you forget you are listening to a portable device.  It rather sounds like a good desktop I would say .Ive heard of people comparing the sound quality and soundstage to the Chord Mojo and even though I haven’t yet compared or tried them together I can’t comment on the same.
 
Filter settings :
 
The M2 Pro has some DAC level filter settings - Sharp SD (short decay), Sharp LD (long decay), Slow SD, and Slow LD. I couldn’t exactly understand the function or changes in each of them but they did alter the sound signature to certain extent where in the Sharp SD sounded the most neutral and sharper treble whereas the Slow LD seemed to have slightly more bass and warmer sound.
 
Even the power handling capacities are very good. It could drive my HD598 , Grado  325, AKG K702 etc with great authority but I did end up pushing the volume to the higher limit . It doesn’t have any gain settings to increase the power output so I am not sure if it will drive the more difficult headphones like the HD 650 or higher impedance can to their best but it should drive them fairly well and maybe adding the Aune B1 amp would make it the ideal setup.
 
UI,Features , battery life etc.
 
The UI and controls are a little odd or different compared to what I am used to on the FiiO or Opus but it doesn’t take more than 1-2 days for getting used to . Since the play / pause buttons also act as navigation button and each button has multiple functions as you can see in this quick guide below.
 
The M2 has a really quick boot time , barely a few seconds . I couldn’t find any sleep or standby mode feature as such but with such quick boot and playback from the last played track it’s probably not needed.
 
The custom software is very simple ,basic  and easy to use overall . It has a very old school 2D feel to it without any animations or much efforts put into the UI design .
The UI menu has 4 basic options on the home screen, Songs-Folders-Playlists-Settings. The menu can be controlled using the buttons below the screen as well as the volume wheel on the right side. You can find the detailed options in settings etc in the photos below. 
 
The software on the device at the time of my testing *almost 1.5 months back* was pretty basic with the play screen not showing album art for some songs and also the volume wheel only works when you are on the play screen , incase you are on the song list or main menu etc it acts as the navigation wheel which can be a little frustrating if you wish to suddenly change the volume in between.
Some other major features like gapless playback , Equaliser etc are missing .
 
Overall there is no lag /crashes or such issues with the firmware but still it seems somewhat half baked and could do with a lot of improvements overall . Hopefully Aune is working in better firmware in the future and will fix the minor issues soon.
 
 


 

 
 


 
 
Battery Life
 
I could get about 7 hours , give and take 20-30 minutes of  juice out of the M2 Pro in each charge. Not that great but not too bad either for a high end DAP which comes with a class A amplifier which are known to be heavy on the battery . This also probably the reason the device gets tad bit warm at the back panel after few hours of usage. Even with regular 2-3 hours of listening, you probably would need to charge the M2 Pro twice a week.
 
Conclusion :
 
Ideally if you are someone like me who just need a high end DAP to play your high quality DSD, lossless music etc and do not care much about the UI etc and other fancy features , the M2 pro would be perfect for you.  For others looking for a complete player it might be a good idea to wait for Aune to fix the smaller issues . The beauty of the player lies in something a lot of great DAC’s don't get it perfectly – pushing the sound quality to perfection at a VFM price point  , something which usually can not be fixed or scaled by software or firmware upgrades.  Either the best sounding one's without any major flaws will be extremely expensive *1000$+ or the other fully packaged player at the 500-600$ price point would be lacking in sound compared to the the M2 pro.
 
If you were to purchase the Aune M2 pro purely for its unmatched sound quality under 500$ it would definitely be a very a great experience and you will definitely love it but for some folks it could be difficult to ignore some of its basic shortcomings like limited playback , single memory card slot ,  limited play list support , lack of digital out . So you could wait and watch if Aune improves upon the M2 pro to make it the perfect player.
 
 

 
 

 
 

 
 
 
 
 
 
 

    
 
 
When asked if I wanted to take part in this tour I quite quickly replied with an overwhelmingly resounding, YES! After hearing how awesome the X1s was I absolutely had to hear the other offerings in Aune’s lineup as well especially in the Digital Audio Player (DAP) realm. So for this I must give a huge thank you to both Aune for accepting me and NMatheis  for inviting me to this outstanding tour. But without further adieu allow me to express my thoughts into the Aune M2.
 
 
 
 
The Opening Experience
 
    The opening experience of the M2 I’m not exactly sure if this is how it comes from the factory of if it was only for this tour. What I mean by this is the M2 actually came inside an Aune B1 Portable Headphone Amp. case and I’m highly doubtful a production unit would come packaged as such. In addition, the only thing included with said package was a micro usb charging cable and the user manual. So, for this reason I cannot justify giving any sort of unboxing experience impressions on the Aune M2.
 

 
 
 

 
 
 
Construction
 
    As we were, onwards and upwards and I right? So how’s the build quality of the Aune M2? This is only my second experience with a designated DAP so my experience is respectably limited but I do still have a pretty good idea on what’s well built and what needs some work.
    As for the M2 I firmly believe that the construction is sound. The aluminum framework feels both smooth to the touch yet hard if that touch were to lose its grip. The screen is large enough as to have a nice sized font, thus no squinting is needed. The volume button on the right side of the unit is beautifully responsive yet provides AMPLE volume selection. Not once during my time with this unit have I wished for a half volume selection, even when I’m listening to the M2 when laying down to rest when my ears are at their peak sensitivity have I had an issue. Also on the right side of the unit is the SD card slot which presented itself it’s own issues, but we’ll touch on that later. On the bottom there’s the volume port and micro usb charging port.
 
Functionality
 
    This is something I look for, perhaps even more than build quality. How easy is it to use and what’s more on top of that is how effective is the navigation? In the terms of ease of use the M2 is quite simple. Though one will have to play with it about a minute or two to figure out what’s he back etc… but once that’s down it’s pretty smooth sailing.
    Well smooth sailing so long as you’re card reads. I know that 32gb is not the max size that the M2 can register but that is the only size that I was able to get to work. I tried 2 separate 64gb sd cards and received nothing but a “read TF failed.” Forums mentioned it had to be formated as “FAT32” so I tried reformatting, but that option never appeared so I simply purchased a 32gb card and have had no problems since.
    The ability to sort through songs is still not what I wish it would be. Say I’m in the “C’s” and want to listen to a sone in the “T’s” and what more I’m not sure of the folder or artist said file is in. My only option is to continuously click forward until I finally arrive at the song I’m wanting to hear. There’s no option to fast search. Now I’ve been told a solution to this is to arrange your music alphabetically into folders but why would I want to organize over 1,400 songs when I feel this is a relatively simple software solution. My phone’s music player had this ability, as does the Ipod Classic.
Sound
 
    Alright, and the main event is upon us. How is the sound quality of the Aune M2? From my time of listening to this I was delivered an experience that expected to receive. The audio came through very cleanly and on normal sensitivity headphones these were pretty impressive, but on super sensitive ciems such as my Empire Ears Hermes it was respectable but still had notable hiss. Now the use of the Ultimate Ears buffer jack fixed this, but it was still present nonetheless.
    Now, getting back on track I really enjoyed the DAC equipped, the 4490 produced wonderfully clean sound that had quite impressive bass extension that I truly enjoyed on my B&W P7, the headphone I’ve had the longest and have well over a thousand hours with. I know how it sounds and has become my go to headphone when reviewing an amp or dac. The P7 has some of the most beautiful treble I’ve heard at its price range with very smooth and emotion filled mids with subtly warm bass. The M2, to my honest surprise, didn’t alter any of that but instead but instead accentuated them. The sound was just smoother and more easier to the ears. The musicality of my P7’s remained which is exactly what I want and expect, however the degree it was increased or rather the music was reproduced isn’t much different than what I expected.
    
                                                       
 
 
Conclusion
 
    To sum up my thoughts, the Aune M2 retails for around $350 depending where you search and for that price I got pretty much exactly what I expected sub some SD card annoyance.  The construction is solid and the UI is quite simple yet nothing extravagant (doesn’t even have the ability to show track images). The sound quality is what I expected and makes for a VERY sound investment for anyone looking for a modest priced DAP. The internal amp has some serious punch easily able to drive whatever I plugged into it (see my personal inventory for list) and the dac’s ability to reproduce the audio signal being pushed through it was great for its price. The M2 digital audio player despite having some slight drawbacks is a solid dap for those in the market.

 
Also, don’t forget to check out my unboxing and review videos! I really appreciate it and let me know what you think, if the review helped you don’t forget to hit that thumbs up button. Till next time my friends, stay safe.

 
*Disclaimer- These opinions are solely mine and we're not encouraged or solicited by Aune. The Aune M2S was bought with my own money and as such is subject to my scrutiny. These opinions are honest, fun and full disclosure...
 
Im not one to jump on trends quickly, and I will do much research/reading before I buckle down and actually decide, it's hilarious I wish you could see the stages I go through. That's neither here nor there though. My background is simple. I grew up surrounded by music and when old enough I sought to find what music meant to me.
When I was young my first experience with a Hifi device would be the Iriver IHP-140, in the summer of 2004. I had only limited experience with audio confined to tv, and radio at the time so it would be my first eye opening experience on how close a device could bring me to the music. Unfortunately for myself I would go on to break the device in a year and wouldn't have another "HIFI" experience until my purchase of the Sony PCM D-100 last year.

The Sony was wonderful albeit cumbersome. I knew what I was getting into with the limited UI, restricted file number, and odd file display setup. Nothing mattered though when after working all day, coming home and hooking the PCM-D100 to the Meir Corda 2sidestep and listening to the Sony Dr-Z7 (thirty year old headphones) deliver me into sonic bliss. Black background, great separation, very revealing, however also cold and analytical with a hint of warmth if bass boost is turned all the way up. It was what I considered a great reference to test all others, especially with different buds(which I never got a chance to get too crazy with).

Fast forward to now. I no longer own the Sony PCM-D100, having sold it to get by some hard times. I now find myself with the beast from the east, Aune's M2S.
When I knew I would have my opportunity to replace my old DAP, I started looking high (Sony PCM D-100,LPG,AK240SS,Fiio X7, L&P L5pro) and low (ibasso dx80/90/100, fiio x5, L&P L3), and settled on this little blue nugget that stood out from all the others. Looking at the main site (http://en.auneaudio.com/index.php?s=/Home/Article/detail/id/105.html), it's easy to be quite taken and I was; looking at the carefully thought out design and layout was "B-E-A-Utiful". However, what really caught my eye was the DAC used inside this blue beast, the AKM AK4490 32bit DAC chip also used in the AK380. Being in this hobby it's always nice to want to be on top with the very best available to you so you can get as close/personal with your music as you feel you can. I feel what Aune has done is nothing short of that. However, when we factor in price, build, design we'll see that at least as far as I am concerned, they gave back to the community and cemented their status in the game as a respected house of sound and makers of fine quality audio devices.The Aune M2 comes in three flavors, however per this review I will be focusing on the M2S as I don't/cannot compare the others on hand. I won't go into detail with the differences as that has been covered already, so lets break it down.
 
 
Design/Ergonomics
  
 
Three buttons in the front, sidewheel, power button up top. I love this setup, very simple no thrills down to business attitude. Straight to the music.
It is limited to one SD card slot which even for myself is a little wrinkle. The feel in hand is nice for a right handed person, and at least for me is akin to holding an old cassette player (when paired with the B1) which I rather like. The UI, while basic in most eyes wanting things like album art,swiping motion, touch screen, blutooth, wifi, DNS are all things I don't care for or use anyways (coming from a guy who owns the Nokia pure view 808, that should say enough about me). Folder browse at the moment is the only option, though I have reached out to Aune and it seems at least that more options are forthcoming (new firmware soon!!!). I've always been fine with folder view as this is how I have my library set up with flac and cue files. So in that regard I feel like this truly was an early birthday present. It was made for me in mind. While things like digital out and coax are things not yet implemented, these are things Aune does have in mind implementing with the device later down the road. Again, I'm fine with just line out, though the lack of DAC function through the computer is one I can agree with others as being a MANDATORY feature. Besides the lack of a proper updating of the library where after the initial load on the card, if you put more artists/folders they will appear at the end of the abc order of the first load, typically being abc in the second instance. If any of that sounds confusing, it is when you look at it. Basically it just amounts to disorder, which for me amounts to a tiny niggle. When comparing to the Sony PCM-D100 for me its an upgrade on the UI and overall pocketability. Barring these slight issues, once rectified I'll truly be without criticism.
 
 
Sound
Ohhh man. Haha, yea I'll start it like that. First impressions plugging up to the MEE P1 (look out for that review forth coming) in the B1, Aune M2S combo was magic!
To my ears, and now subjective/selective memory, this brings me closer to the magic than the Sony PCM-D100 had. I have much love for that old Sony but man, the liveliness of the music, detail retrieval, separation amounts to me not having second considerations. Additionally, I'm benefiting from a background that's just as, if not more black and spacious.
Using the the Sony DR-Z7 on tracks like, Nostalgia 77's quiet dawn, brings goosebumps, a swell of emotion and the feeling like your sailing along the milky way. Other performers like Janis Crunch and her recent release (while not very good production wise, I can hear a noise floor I feel higher than other recordings which is shame since it sort of smears the overall beauty of her piano work) is forgiving enough though very obvious with any shortcomings in the production itself. What really sealed it for me and really got me going was Pink Floyd's Wish You Were Here (Rare 1984 UK limited edition Nimbus) Shine On You Crazy Diamond Parts1-4.
Its always been one of my favorite tracks of theirs and having listened to it so many times throughout my life I thought I had heard all the little nuances, however I would be proven wrong. The recording is THE best I've heard. Complete blackness provides the perfect canvas for Pink to lull you into their world and steal you away once again. Of course, it would be the saxophone at the end of the song that just SEALS it for me. You can hear that sax go all the way back, back, back, back, to the end of that hallway. Its pure bliss, and if it isn't already apparent I'm not gonna be saying many more negatives about the player, because essentially it does what it should very well. However, it still is limited in what it can do for you in regards to augmenting sound, if EQ is your thing, you wont find it here. What you  will find instead is 4 digital filters, which for me while not providing the same flexibility as EQ, do a fine job in allowing the player to sync with a different pair of headphones/genres.
 
I'm going to now tread murky waters and for INFORMATIONAL purposes ONLY will be sharing work that is NOT mine in regards to the filters and how they affect the frequency, if this breaks rules or offends anyone I will make the necessary changes. This is from a Blogger by the name of

Lin - Xi ink,  (​

http://blog.sina.com.cn/s/blog_60c1aacb0102w3ht.html) All credit and praise be directed at her/him?
 
 
 
As you see rather than looking at EQ, we simply look to the rates of decay, adjust and move on per genre or headphone with the feeling your trying to illicit. For me it works out very well, but I can already hear people wanting more control which isn't a bad thing. However I am content in this regard. 

The Aune with the B1 stacked, is really where it's at for those wanting first hand accounts. The Aune M2S by itself does very well and capable through HO, however it excels LO and paired with the B1 the levels at which we climb go up and then some. What's great and has already been spoken of more thoroughly, is in how well the B1 just steps aside and gives the source room to grow. No coloration, no distortion. For me paired with the P1's I have no hiss, though remember user/equipment subjective. I have plugged the Mier Corda 2sidestep into the Aune. However, I didn't really find it all that great. Nothing against that amp, which I did find appropriate for the PCM-D100. What we hear combined with the M2S is something more veiled, with more noise. Not terrible noise mind you, but it's enough to make me just plug back in the B1. The last thing I would like to touch on is battery life, this is a huge feature that ultimately brought me to the Sony. Comparing to the Sony, which I believe it sits somewhere around 9 or so hours. With the Aune M2S we see about 7 hrs of playback, with a built in battery. Looking at my application for this player paired with the B1 has been limited to bus trips to and from work, with sprinkled time throughout the evening, and I don't typically charge till somewhere after three days of use. Again, while I love music I'm also living life, so it's not a deal breaker.




Conclusions
Looking for a player myself I considered a few things. Well thought out design and implementation of resources, ergonomics/handling, price, UI and of course sound. I won't lie, when it came down to it I took a shot in the dark with Aune and after a solid month have been happy. No restarts, some files not playing properly, but all in all very positive. For those looking for an affordable DAP, without bells and whistles looking for that magical connection with their music all over again look no further, but don't necessarily think that the M2S appropriate. The M2pro will do the job just fine and allow you to spend more on interconnects/amp or headphones. Nothing wrong with that. Also as a final conclusion, no one is gonna be able to relate, or very few will. The combination of M2S,B1 and Sony DR-Z6 is AMAZING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!  *pant*pant*pant*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Thank you Aune, thank you Head-fi.
Hope you enjoyed my ramblings


Final snippet- When the areas I have a concern with, file compatibility, cue file accuracy, UI, ABC disorder as well as digital out, coax out are fixed/implemented I will be changing this to a 5. We'll see what they can do for this little blue dude over time.
 
 
 
Edit- added additional pics, small editing/rewrites

I recently acquired Aune M2S and I found out that there is barely any update reviews on this excellent DAP so I feel compelled to write something about it.
 
I have had many many different DAPs in the past and my favorite one is AK120ii. This DAP has been my daily doze of audio drugs for the past year and half and it’s keeping me away from trouble so far. I mean wallet wise,it works. The SQ is very very good and I thought I couldn’t ask for more. I enjoy full-size headphone so whether playing it straight or  couple it with B1 or my fav amp Mk3B+ in balance I get a sound that’s comparable to desktop rigs. I used to own RSA Intruder and it works really well in this regard too. Wonderful !
 
In this review I’m not going into too much detail about the specs and build other than the SQ and the comparison to other DAP or DAC that I currently own. This is not a review units so I'm not obligated to say anything nice if I don't want to. Here it is:
 
UI :
Navigation is pretty simple and basic if you are familiar with FiiO or Ibasso DAP then this is a piece of cake however, the DAP is on firmware 1.22 at the time of writing and there is more work to be done and it needs to support 200GB micro SD card since it has only one slot. No support for album art, no playlist, folder browse is in random order not alphabetical, and no digital out nor stand alone DAC support.I also managed to squeeze about 7 hours playing time at 80/100 vol. Future firmware should be be able to fix all this. I hope. Aune please!
 
Aune DAP has three different models i.e.M2, M2 Pro (both in black and silver) and M2S in blue color only and this review is for the flagship model M2S.
 
To make this thing easy I’m going to compare it to my trusty AK120ii so I hope some of you have a clearer understanding on how it actually sound.
 
How does it sound ?
 
In one world it is Excellent ! Out of the box you can tell that there’s a huge potential and promising SQ and with more burn in time this DAP becomes more and more mature.
M2S is dead neutral with no warmth or brightness and it has a lean texture but in no way it is thin or anemic like some DAPs out there. Nothing is being exaggerated every freq seems to be pretty equal in harmony with each other. You can hear everything very clearly from bass, mids to highs. The DAC is quite revealing more so than AK120ii. It is apparently the same type of DAC as flagship AK380 i.e. 32-bit AKM AK4490. It plays DSD files but I'm not sure whether it is native or converted PCM like AK120ii as I hear no different between the two DAPs.
 
Couple things that l notice really stands out more than AK120ii is the superb black background and very very transparent sound.
 
 If I can describe between the two perhaps like this:
 
AK120ii is smoother, softer, a little velvety background and it has slightly thicker notes and thicker woolier bass with less detail and impact while M2S is lean, very very clean and very transparent with better..no much better micro details that comes to the surface. With AK the micro detail is presented in subdued, softer ways.
The bass with M2S is very detailed and has more punch, with customizable attack and decay time by using the four different filter i.e. sharp-short decay, sharp-long decay, slow-short decay and slow-long decay. AK120ii bass note sounds almost similar to slow-long decay but still with longer decay time making it feels slower and less-groovy not in line in a certain songs ( faster/groovier bass line).
Listening to Justin Bieber new album...no I am not a fan I am far too old for this but I will have to admit his latest albums is very good, mature and musical. Anyways, the song called "Company" has a nice contrast of texture between the vocal, background and punchy bass line. With AK it sounds smoothed out less pronounced while M2S has tighter, punchier better groove to it.
As with Jess Glynee song "Hold My Hand" there's a really dancey syncopation between the piano riff, beat and the bass line in the chorus and again, AK makes this all smoothed out with less dynamic and loose timing but with M2S it it a DANCE music all right, very toe tapping one.
 
M2S superb black background makes depth and layering of instruments much better and much clearer than AK and it has bigger sound stage too, wider and spacious. Both DAPs have very good tonality and M2S has a bit more fundamental note. You can hear the resonance of the acoustic strings, decay and tone of the piano, the shrieking violin and sizzle and tone of a ride cymbals. Vocals are more articulate and present and just a tiny bit more forward than AK. Try listen to a classical pieces with solo instruments such as violin or cello and I bet your ear will be heavily rewarded with the sound. If any of you is familiar with the artist “Enya” than you know what I’m talking about. Listening to Enya’s music with M2S is such an enlightening and euphoric experience.
 
Headphone Pairings
 
Both DAPs sounds very good with M50, HD650, 700 and LCD X but however, I prefer AK with HD650 on balance it has much better synergy between the two due to the slightly warmer tonality of AK120ii. I have a modded my HD700 and I use Audeze stock cable with it. Now it sounds much better, less treble glare, deeper sound stage and much better bass. It behaves very close to my LCD X and M2S makes them sing with more clarity and punch. IMO, better pairing is with a slightly warmer phones or iems but this is just my liking. I don't use IEM so don't ask or buy me one and I'll tell ya.
 
Portable Amps Pairings
 
Together with M2S I also bought Aune B1 Amp. Very good sounding amp, clear and very transparent but however I prefer to pair my M2S with MK3B+ in balance mode. This ALO amp has a slightly warmer tonality that also improve texture, layer and deeper bass. This combo is absolutely freaking amazing with both HD700 and especially LCD X ! The clean sound from M2S with the added wee bit of warmth sounds just perfect to my liking, very very musical and engaging. Layering and separation becomes much bigger and wider just like desktop amp. As with the AK, B1 seems to be a better pairing, slightly warm meets transparent neutral amp. B1 is very neutral amp with slight focus on the mids it doesn’t seem to add anything other doing a good job amplifying the source signal. B1 makes AK120ii sounds bigger and more spacious than it already is. The sound is seductive and very very easy on the ear.  Both DAPs are now perfect !
 
Lets go further…M2S/MK3B+ vs AK120ii/Hugo shall we ?
 
Is it too much too ask to compare the combo with Hugo ? Really ? Hmm..why not
 
Most people here agree that AK makes the better if not the best transport for the all mighty Hugo and this is …ahem, was my best combo. I’ll say this, M2S/MK3B+ combo sounds much better than AK/Hugo. You get much better transparency, bigger dynamics, better layering and faster-bouncier-groovier bass note while AK/Hugo has slightly fuller and warmer sound, softer, smoother and bigger but slower bass. Both are very musical indeed. The bass on the first combo is punchier and on time but the Hugo combo has bigger body and impact. It reminds me of the bass comparison between LCD XC vs LCD 2 pre fazor or HD700 vs HD650.
It seems like AK’s transparency and dynamic is holding up what Hugo is actually capable of and I get the feeling that If only M2S has a digital out it will be the best transport for Hugo Ever.
 
To sum this up: Aune M2S is a new generation of HIFI portable music player that uses the latest ARM+CPLD+AK4480 DAC and high bias Class A amplifier that plays WAV/FLAC/APE/DFF/DSF/DSD/ISO/M4A/AAC/MP3/ALAC/AAC and support 32 BIT/192K files playback.
At THD+N 0.0009% you can blast this player and hear No distortion, doesn’t get shouty or brighter it maintains its composure elegantly.  M2S is more than capable of driving my pretty efficient HD650/700 and LCD X with better authority than Ak120ii at 85/100 vol. If you are an IEM user I would think you should have no problem.
AK120ii is still an excellent DAP with built in 128 GB storage plus 200GB compatibility, great UI, desktop quality in balance mode, bluetooth compatibility,DNLA and so on.  Both DAP are great but if you want SQ more than anything else than Aune M2S is the way to go.

Life is full of compromises. I don’t like the word compromises though. It has negative connotations. It smacks of despair, quiet sadness, waiting and never quite reaching that ecstasy, always thinking that if you had just had your way, things would be perfect. Trade-offs is another filthy word for me.
 
My semantic hang-ups aside though, it’s true. Life is often compromise. So for me, wherever possible, I like to at least strive for perfection, my way. I can’t get this always…in fact, it’s rare that I get that pinnacle, but when I do, it’s that rarity that makes it all the sweeter.
 
I think that’s how the designers of the M2 feel. They have made no compromises, and its cost them somewhat, but the reward is great.
 
I was given the chance to listen to the Aune M2 in return for my honest thoughts. I was not given the unit, and sadly need to return it soon. I was also given the B1 to try at the same time. This review covers both, but will primarily focus on the M2.
 
Both the M2 and B1 arrived in boxes made for the B1, which I found amusing, but understood completely. The M2 was very obviously a review unit. I didn’t need bells and whistles along with choirs of angels to appreciate it after I heard it.
 
Looks-wise, the M2 is a questionable exercise in industrial design (in fact it’s a tad ugly), but it is very functional. Three buttons on the front, a workable screen, headphone and line out ports on the bottom, along with a mini-USB cable port. The volume control is nice…it’s a recessed analogue potentiometer on the right side of the unit (I liked it too…very nicely done…a buck against the trend to slap a giant knob on the side of a DAP lately). It’s positioned below a mysterious min-HDMI port that I am a little clueless about. Mid-way down the right side is a micro-USB card slot.
 
The B1 is also a little odd. It has two clear panels on one side, and two faux, softish-leathery-ish, something-synthetic-but-nice panels on the other side. I noticed ALO did the clear panels on the new Continental too. I question the functionality of this and being the contrarian turd I can be sometimes, think it’s an unnecessary waste of time and effort. The B1 has a slew of very self-explanatory buttons on either side of it, and a nice volume control knob on the end, between the headphone out and the line in ports. Notable items here: the power is turned on using a switch on the side instead of the volume knob, and there appears to be a button specifically for checking the battery. In addition, you can switch from Class A to…erm…not Class A…
 
Enough of my shallow myopic whining though. On to the good! The excellent, the point of the whole exercise of making a DAP: the sound and the UI. Yes. UI is important. If, by the time the music is playing, I have collapsed in an apoplectic fit of rage, what good is beautiful sound?
 
The M2 sounds amazing (I used FLAC files, at 16/44.1). Detailed, spacious, excellent instrument separation, not sterile at all…I loved listening to it. It clearly brought the best out in all of my headphones (which are mostly 32 ohm, Grado or Magnum variations built by me, and VE earbuds). Seriously, I would take this player over my Pono and X5 (first gen) happily. I would do this very easily except for one thing. The battery life. The M2 lasted a day at the office with me (about 3, maybe 4 hours of play at very moderate volumes in a closed office), and needed to be charged. It’s abominable. It’s clearly the cost Aune had to bear for that glorious sound. I can only hope and pray they manage to figure out how to fix the problem.
 
All is not lost though. If you want 95% of that glorious sound, all you need to do is buy the B1 amplifier. Its battery appeared to last a little longer (I didn’t do conclusive testing).
 
The M2’s interface was actually a breath of fresh air for me too. Three buttons. Middle one is select (short press) and back (long press). The buttons to either side are up and down/left and right. I loved it. And to cap it off, there is even a mode in settings you can select that gives you hints on how to navigate. No fits of rage here. Just happiness, and the ability to turn off the help notes after five minutes of tootling about testing things.
 
In summary, if Aune could fix their slightly dubious industrial design choices and battery life problem, I’d be selling my other gear to pick up one of their units. I am sincerely looking forward to seeing what the next generation of the M2 looks and sounds like (and how long its battery lasts). As for the M1, its nice and all, but I feel the M2 holds more promise…
 
*edit: forgot to mention this...the M2 does not act as a USB device. You can charge it via a USB port on your computer, but you can't use it to add or remove files from your microSD card.

I typically run and hide when someone wants me to listen to a transparent device thinking, oh no, another weak, lifeless, and non-fun way to listen to music. But here I stand singing praise for the Aune family and my Hidition NT6pros which are known for their stellar transparencies. What I am trying to say is that IMO the HD800 is an example of something that is done wrong, unless driven correctly bring it to life. Yes I love the HD800 and will eventually buy one – especially with the new JJ triple tweak mod setup that I am using on my HD700s right now. But out of the box played through an underpowered, bright source/chain can be painful at best. The Aune family and the NT6 on the other hand are versions of transparency that actually bring dynamic life to the party. You just have to hear them yourself to understand what I mean. However, I will do my best to explain below.
 
Disclaimer: This was a tour DAP that came with the B1 amp in tow. I did not buy this setup ......... yet. Only because I am trying to decide if I am going to go for the upgraded Pro version. Anyways, this is from a week of listening to a tour DAP/AMP stack. I tried it alone and stacked as you will see in my notes below.
 

Listening Notes

• M2 Stack/Single: Wow, other than the Paw Gold, this is the only other no stack DAP. No need for an amp, it is clear, full-sized, wide/deep, and full bass response.
  • Alone: By itself, the M2 is very full sized sounding with fantastic bass quantity and quality that makes it stand out without muddying the mids. The signature has enough spaciousness that it doesn’t justify an amp either. I would love to hear the M2 and PAW side by side, but they are very similar going from memory with the PAW being a little more elegant and refined. Need an AB to know for sure.
  • BH2: The BH2 adds a more natural decay or bounce to the base and a little more musical feel, it adds a little more brightness too. While the BH2 addition sounds better to my ears, in a natural fun way, it is not enough to justify the burden of a stack.
  • B1/CIEMs: The B1 is very close in signature so hard to hear a difference in an AB. It might be a little more clear and a little more wide, but I am splitting hairs. To the uninformed it would sound the same. No value for adding the burden of a stack.
  • B1/HD700: This is a tossup as it sounds better with the additional power, but for convenience, I would chose to go without. However, if I had the B1 handy, I would use it for the added SQ. The addition here is the ability to turn it up further without fatigue. Turning up with the B1 brings me closer to the music for a more detailed SQ that would be fatiguing without. At night at low level listening, the B1 is not necessary, but I find that when stacked at night I do end up using it which interferes with my intended going to sleep. But it makes for a fun listening session.
  • B1/LCD2.2: Absolutely needs the B1. Yes, it sounds great direct, but the B1 takes everything to the next level. Direct, the volume is high enough that the treble glare kicks in a bit, but the B1 take that glare away. Better yet, the B1 clearly is a dream combination with the LCD2.2 providing neutrality, transparency, and power that the LCD2.2 needs while effortlessly driving it without adding the treble sharpness many amps do. This is the best I have heard the LCD2.2 on the transparent side of the spectrum. I love the LCD2.2 on a warmer setup too, but I am preferring this pairing as my favorite right now.
• M2: This is a very neutral DAP with full extended frequency response.
  • Build/Looks: While it looks nice enough, it is obviously a mid-range looking product, but then again, so is the $2K Paw Gold. It is not too big or too small, or too anything. It is a good inconspicuous working model that is not likely to get stolen. My AK100ii would get stolen quickly if I left it unattended on a table at Starbucks – the Aune, not so much.
  • Neutral: This DAP has become my new definition in neutrality as it seems to give equal emphasis across the frequency range from meaty sub bass to delicate cymbal hits to textured mids. I have heard neutral before, but typically comes out as boring and taking the excitement out of everything to play fair. This is not the case, the M2 finds excitement everywhere at the same time.
  • Treble: Nice smooth highs that add detail without too much fatigue. There is a slight glare when turned up too high, however lower volumes are very full so high volumes are not required for detail. The B1 removes any glare from the treble if this was ever an issue. The high quality clocks have removed the treble harshness that haunts me in much of my audio gear providing treble clarity that I have not heard before with a transparency that gets the noise out of the way so you can hear the most delicate treble sounds such as a light bell tap. The clarity also puts that light bell tap into its own space where you can actually hear the resonance of the bell hit echoing in the staging.
  • Mids: The extended highs and lows hint at a fun v-shape signature, however, the mids are not recessed at all. The mids are neutral to the rest of the signature, but very rich and detailed thanks to the well-integrated bass/treble to create a rich whole.
  • Bass: The bass reached nice and low and is fast enough to provide quality and emphasized enough provide a full sized signature. The M2 power shows well here allowing the bass to stand on its own without the need for a separate amp. The bass may have a mid-bass hump for emphysis, but it doesn’t step on the sub or mids frequency at all. This is an example of DAP bass done right.
  • Sound Stage: The full size SQ implies intimate which implies small sound stage. However, while in the 1^st row or on stage in placement, you can hear good depth and layering showing off a larger stage with great detail. There is also nice placement and distance between instruments that allows the timbre to shin, especially in instrumental pieces.
  • Dynamics/Effortlessness: The M2, especially when stacked with the B1 is a great example of effortless dynamics. At low volumes, the spectrum is still punchy, plucky, and dynamic. At higher volumes the M2 gets a treble glare with full sized cans that is eliminated with the B1 stacked. The stack is a great example of effortlessness as it doesn’t get louder with volume, just moves you closer to the music adding intimate details like only the highest end overdone equipment can. There seems to be an enormous amount of headroom here.
  • UI/FW: It works, easy to use, allows you to hear music, without the UI clutter to confuse things. If you are a UI/FW freak, this is not the DAP for you. If you just want to turn it on quickly and listen, this UI is quick and easy.
  • MicroSD Card: Only one that is fine. Reads faster than I have experienced before. Only reads when changed and automatically. The only downside is that I had issues with one of my MicroSD cards where it had trouble maintaining the library. It would lose the read and freeze or it would rescan and start the list over. Hopefully, it was an issue with just this one card, but I only tried two and it worked fine with the other.
  • External Buttons: You can use the external buttons to control the music without looking at the screen which is a real plus for me. However, the screen turns on with every button press wasting battery even if I am not looking at it. Hopefully, there is a menu option to disable the screen when using the buttons, but I am too busy enjoying to care during the tour. I am on a mission to hear every song on this DAP, it is that good.
  • Instant On: While not instant on, it feels like it compared to the rest of the DAPs I have used. It turns on within 5 seconds.
  • Card Scan: I changed the MicroSD card a few times and was shocked at how fast it scans. I have not timed it, but it seems like it is only about 5 seconds for a full 32gb card. It is crazy fast in comparison to any of the competition. Better yet, it know when I change cards when off, and automatically scans when turned back on. This is MicroSD card management perfected as it is quick and only when needed – automatically.
  • Battery: 7 hour battery life sucks, but it is the price I pay with all my audiophile level battery operated components with only one exception – the 80 hour BH2 amp. What’s worse is that my LCD2.2s seem to eat the battery even faster – maybe 4 to 5 hours tops. This means that charging is a daily chore if I listen for two or three hours at night as I don’t want the DAP to fail on me the next night mid-session. However, given the awesome SQ, I don’t care – it is worth it.
  • Transparent: I am hearing thing that I have not heard before in music in a good way given the extreme transparency. The transparency must be a factor added by the clocks that are mentioned in the literature, but the noise is spooky gone and very noticeable. Once you get used to the transparency, it is hard to go back to the competition that once seemed quiet. This transparency creates a sound stage with massive space between and great timbre as mentioned before.
  • Musical: This is a new kind of musicality for me that I have not experienced in a hand held format before. Yes, I am doing the old cliché of listening to my music catalog anew as if it was for the first time getting lost in the music.
  • Hot/Hot/Hot: Yes, class A gets hot. Yes, class A stacked on another class A device gets even hotter together. No, I am not burning myself, but listening at night, I have to keep the stack away from my covers or I feel like I am in an oven given enough time. Yes, I woke up in a sweat when I fell asleep with the stack on the covers on my stomach.
  • No Opt/Coax Out: This is a feature that I use a lot with my AK and concerning not to have it on the M2 if I switched to an Aune stack. However, given the SQ, I will have to try using it as a source for my speakers to see what happens. Regardless, I use the digital out to test my music at Headfi meets don’t want to color the sound in the units that I am testing. I would miss that functionality.
• B1: At first glance using my CIEMs with the M2, I thought what is the point. The B1 sounds exactly the same as the family signature in the M2. However, bringing in the big cans, especially the LCD2.2, the point became quite clear.
  • High Volume/No Treble Glare: The M2 gets fatiguing at high volumes as the treble glare sets in, but I cannot go that high with my CIEMs to care. With the LCD/HD everything changes as I am playing in the higher volumes. Even though the amp sounds exactly the same, I can go as high as I want without any treble glare. Better yet, no distortion of any kind allowing me to move as close to the music as I wish. Turning up the volume doesn’t make the sound louder, just bigger and closer with more detail. This is the must that I check for when buying high quality components ensuring headroom.
  • Looks: The B1 is nicer looking than the M2 and most of the other portable amps that I have seen. It is certainly not as small and convenient as my BH2, but is very neutral and transparent vs. the BH2 colored approach.
  • Bass: The bass on the B1 is very high quality, hard hitting, and transparent. I cannot see anyone complaining about the bass from bass heads to audiophiles.
  • Battery: The battery life on this A class device sucks just like the M2, but it is worth it for the SQ it produces. Again, it is about 7 hours and quite a bit less using my LCD2.2. But the LCD2.2 is driven as good as I have heard it with the B1.
• M2 vs. AK100ii: The AK is a great DAP and I will not be selling it anytime soon. It is even better stacked with my BH1. However, having the M2 around, the AK is going to collect dust. The M2 + B1 is crazy good in SQ at desktop level and better than my AK + BH2 – period. On second thought, maybe I should sell the AK and use the funds to buy the M2 pro plus the B1 and use them as a package. If only I could hear the pro vs. the non-pro to see if it is worth the upgrade. Sorry AK, the Aune family is really that good.
• Personal Conclusions: This is my personal thought process having heard the M2/B1.
  • M2 - Gotta Have It: This is a stand out in terms of SQ that I need to add to my arsenal. It is the best chain that I have heard for my LCD2.2 which have been collecting dust lately. It also matches my NT6pro and HD800 taking them to new levels of portability.
  • B1 – Gotta Have It: While this is only the second DAP that can get away stackless other than the PAW GOLD, it sounds better with my HD700 and especially my LCD2.2 when stacked with the B1. I absolutely do not need the B1 when going portable with my CIEMs – no need. However, much of my listening will be at night and likely now with my LCD2.2 so I will need to stack.
  • Finance: Given the price of my AK100ii is equivalent to the M2pro/B1 stack, I am considering swapping them out with a sale/purchase. However, given the short battery life of the Aune family, I am hesitant.
  • Battery: As much as I hate stacks, I have an Anker Astro E4 Classic 13000mAh Portable Charger that has two USB charging ports that can be added as a third component in the stack to keep both Aune products running long term. Then I can remove the Anker and charge independently every third or fourth day. Now that’s a stack, ouch!
  • Sound Quality: Certain chains stand out as exceptional when paired with the right HPs. I like having variety in my signature which I have accomplished with a LCD2.2 at one end of the spectrum and an HD700 at the other end with my CIEMs being a good middle ground. These HPs pair well with my desktop and previously stood superior in that chain with the portable being an afterthought for convenience. The Aune stack has offered a new desktop quality SQ setup that provides a new signature that rivals my desktop while providing variety in signature. It is hard to describe the transparency that this provides without hearing it yourself. The transparent stacks that I have heard before all came at the expense of a sharp treble that I found fatiguing. Aune seems to have cured my treble fatigue through proper clocking and upped the game in SQ for portables in a big way.
  • Vs. Paw Gold: Going from memory, I want to believe that the PAW still beats the M2, but having spent time now with the M2, I am not so sure. I am anxiously awaiting the tour PAW to check my memory. Regardless, I can say with 100 percent certainty, the PAW Gold SQ increase is not worth the $1500 price difference to me. I would have to get a really good deal on the PAW to pay that much for a DAP that is at high risk for loss or damage when I can get 95 to 99 percent of its SQ with the Aune stack at $350 for the M2 and $150 more for the B1. I can stand to lose $500 even though it would hurt, but $2K is too much to risk for the PAW to leave my house eliminating much of its usability/value.
  • Vs. MOJO: Had the MOJO on my buy list, but the M2/B1 stack is going to replace it and be more versatile for my needs. The hesitation that I have had with the MOJO is that it is very close signature wise with my AK/BH2 stack. Therefore, I don’t get excited when I listen, been there done that. So if there is no real improvement in SQ or difference in signature to what I already have, why buy the MOJO? The M2/B1 stack is very different to what I have so it provides me with greater versatility. Yes, I am going to say it – I also like the overall M2/B1 SQ better than the MOJO. Don’t hate me, I just call them as I see them. That stack will save me $100 too, unless I go Pro, then I lose $50.
  • M2 vs. M2 Pro vs. M2S: This is the real outstanding question right now as nobody has the three to compare. The clocks made such a difference in the M2, that I am tempted to supersize them with the Pro version, but what would that add. Is the base clocks already good enough? The S version makes no sense to me given I have no idea what a Teflon PCB would do for SQ. Anyone? For me the real matchup is the M2 vs. the Pro. Please help with some specifics, anyone?

 

M2 Stacking Thoughts

At first, second, and third listen, using my Hidition NT6pro I was excited to hear a DAP that didn't need an amp to sound its best -"wow, no need for a stack here". But then I started listening with my HD700 and more so with my LCD2.2 and found that stacked, it reached desktop SQ allowing high volumes with no fatigue or distortion. Not only that, unlike cheap amps that get louder, brighter, and fatiguing with volume, this stack just makes the sound bigger, more detailed, and moves me closer to the action as I raise the volume. Being greedy for that last ounce of SQ, now I am unsure and will be going back to the NT6pro to finish my tour turn to see if it is worth the weight. In my use case, I am mainly using it in bed at night to fall asleep after obsessing about SQ for a while so weight doesn't overly matter, but here are some notes that might be useful:
 

• B1 Stack Value: I value the M2 for it unique clean transparency with the best treble I have ever heard. No fatigue what so ever while providing full on treble goodness in detail and reach - plus that tight punchy bass and rich plucky textured mids. Adding the B1 provides these values:
  • Allows Higher Volumes: At higher volumes, the M2 starts to strain and gets that treble glare where it can become fatiguing. My interest in the M2 pro is to see if it resolves this with with an even better clock so your S version may be different. With the NT6pro being around 50 ohms it is easy to drive so I don't really typically play that loud given the CIEM isolation preferring to listen at low volume - so no issue for easy to drive CIEMs. This may be different for harder to drive CIEMs.
  • Mobile or Jamming: When moving around outside or enjoying a particular song, I do like to turn the volume way up for a short while. This is where the stack is of value to me with CIEMs and I will be testing further in the next couple of days.
  • Full Size Cans: So, while borderline for CIEMs, it is absolutely a value for full sized cans. Easily justified for me given my LCD2.2 which they drive wonderfully and best my much more expensive and elaborate desktop in the pairing. They will bring my LCD2.2 out of retirement.
  • Family Signature: The nice thing about the B1 is that it adds power and finesse without changing the perfected SQ that M2 already has. Considered using my BH2 instead, but it changes the signature away from what I like about the M2.
• Stacking Considerations: The M2 and B1 make a pretty stack as they were built to stack together at the same size and shape.
  • Looks: The B1 is much prettier than the M2 adding looks to the equation.
  • Weight: They are very heavy together. The M2 is heavy alone and the B1 is equally as heavy so portable use requires planning.
  • Brushed Aluminum: The brushed metal on brushed metal has a damaging feeling/sound like grinding teeth. If I was to stack them with bands, I would absolutely need some cushion between to avoid damage. Velcro would probably work better, but is unclean when not stacked.
• Battery: Probably a non-issue given the same battery life as the M2, but at 7 hours (or less with an LCD2.2), an extra battery pack becomes a consideration to keep going throughout the day for long term use or flights making it a triple stack. Battery packs like mine are big and heavy adding to the already considerable weight. For me laying it next to me in bed, no problem except for maneuvering to find the forward button given my button pushing habits.

 

Conclusion

This is a definite purchase for me. The question is now the regular, or the pro version that adds better clocks. If the added clarity of the upgraded clocks allow me to go without the stack or if the SQ improvement is obvious, I will go for the pro. However, I am likely to get the B1 too for my LCD2.2 which is a match made in heaven. Here are my final thoughts:

• CIEMs: The M2 has no need of the B1. Go light.
• LCD2s: Get the B1. Good without, but stellar with. The best I have heard the LCD2s in a long time including against most desktop configurations.
• Battery: Sucks, but worth the hassle for this SQ.
• UI: Good enough for my use case of choosing a folder and continuously hitting the forward, FF, or repeat button. However, I need to find a way to control without the screen turning on. Didn't have time to figure this one out, but anything would help with this short of battery life.

 
 
Service

 
I was intrigued by this DAP because I really like the sound of the AKM4490 DAC that I had heard on the AK380 and Cayin N5 player. I was somehow convinced it could compete with much more expensive DAPs and besides, I really like the all brushed metal design.
 
So I contacted Aune and asked if I could obtain an M2S demo version free of charge as I am in China. It didn't work out but I got a fair discount on the MRSP in exchange for writing a review. The contact was very nice and reactive, so I can say the service was quite good.
 
The M2, M2 Pro and M2S can be found here: http://mall.auneaudio.com/index.php?route=product/product&path=18_45&product_id=54
 
The M2S is the higher end model and costs 650$, and it comes only in blue. It is not available in China normally, only for export.
 
The differences can be found here:
 

 
 
Ergonomics
 
I am using 1.1 fw, which is the only stable one in my experience so far. I find the 3 button + volume scroll manipulation very easy and intuitive. I navigate through my files easily and quite fast as you can use the volume wheel to scroll faster, or just skip entire pages. I recommend that you split you files into several subcategories if you have a 128g or 200g micro sd, because the player with FW 1.1 has two limitations:

1. It will not read a list of files or folders over 150 or 200, I am not sure. So if you have over 200 albums in the same folders, the albums in excess of 200 will not appear. Same for files
2. It will not read special characters. I just eliminated characters with accents from folder and file names. I had very few but it could be a problem for others

 
Other than that, my two main issues are the following:

1. It doesn't have a USB DAC function (so far)
2. There is no playlist management (I mean playlists created outside and imported, in M3u format for instance). It would be ok if like on the Lotoo Paw Gold you could add whole albums or folders to the favorites playlist, but it is only track by track
3. The battery life is quite short, I would say 6 hours at most

 
 
Sound
 
I tested this player for about three weeks with redbook and highres flac. My other sources are AK240SS, Lotoo Paw Gold and Mojo. I tested with all my iems (SE Ultimate, Rhapsodio Solar and Galaxy, Shure SE846)
 
I will start with the (only) negative: the player is not totally hiss free. The most sensitive iems (Zeus, 846) will have some hiss, less than with the Lotoo Paw Gold, but more than with the Mojo. I should mention that I am VERY sensitive to hiss, so I guess this level of hiss would not be noticed by most. The player is totally quiet with my SE5 Ultimate and Rhapsodio Galaxy.
 
Other than that, this player sounds very good. The same type of AKM4490 I heard in the AK380 from memory. It is a spacious sound, more width than depth, detailed and precise, yet very liquid. Liquid is the key word here. A sort of effortless musicality that does not sacrifice to detail: bass has authority, even though the player does not exhibit the raw power of the Lotoo Paw Gold, and the rest is smooth and transparent. The M2S is neither warm nor bright but neither aggressive nor fatiguing, but once again without scarifying an ounce of detail. Once again, it could have more depth if you compare to the Lotoo PG, but the Paw is really a champion in that area (and three times more expensive).
 
Note: I have not tried the M2 or M2 Pro so please do not ask me to compare.
 
Conclusion
 
If you do not need a very long battery life and value SQ over functionalities, this player is one of the best sounding I have heard, regardless of price. I think I prefer it over the AK240SS.

Photo courtesy of Aune
 
***Even though the M2 I reviewed is BLUE, it is not the M2s. It's a pre-production model of the standard M2.***
 
[size=medium]Jan. 2016 EDIT: An issue I thought had been resolved with AAC & ALAC playback has not been resolved, so I'm removing a half-star from my review until this is fixed. The issue is that any AAC or ALAC songs over 8.5 minutes are skipped over and not played. Hopefully, this is resolved soon.[/size]
 
INTRODUCTION
I've been very lucky to hear many great-sounding DAPs this year. This product category is exploding at a rate I'm sure many of us wouldn't have guessed at a couple years ago. Today, I'm here to tell you about the newest contender, the Aune M2. I've become a fan of Aune this year, participating in review tours for the both the Original B1 Amp (LINK) and the updated B1 2016 Version Amp (LINK), the Aune X1S desktop DAC/Amp (LINK), and now the Aune M2 DAP. When my buddy @hakushondaimao asked if I'd like to review the new M2 DAP he'd been playing with and help kick off Aune's US Tour of the M2 DAP and B1 2016 Version Amp, of course I said yes. Who doesn't love playing with new DAPs? Hmm? I sure do! Maybe you do, too. If so, please check out the tour thread Aune put up (LINK)!!!
 
Now, I'm not going to lie to you, my time with the M2 has had its ups and downs. Since this was a pre-production, pre-release model, it was running beta firmware. Bugs... Yup, there were plenty of bugs. Take a look at @hakushondaimao's review (LINK). He loved the sound but held back on his rating due to firmware bugs and limitations. I experienced a lot of the same bugs and limitations. Most of the bugs have been fixed, but a lot of the limitations remain. I'll go over those in the review below, but you get a taste of them from my pros and cons above. Okay, enough preamble, let's get on with the review, shall we!
 
Before we start, here's a bit of information about Aune from the About Us section on their website:
 
About Aune
 
As Ao Lai Er Technology’s high quality HiFi brand, Aune has been devoted to developing and producing desktop, portable and car audio products. Founded in the year of 2004, Ao Lai Er owns the largest Chinese audio technology website - HIFIDIY.NET and high end audio brand TITANS. HIFIDIY.NET has 700 thousand members. It’s always been a platform for the most advanced HiFi technology communications and practice. We gained lots of experience from the long-term accumulation, and have released hundreds of kits and parts from independent R&D, which are well received around the world! Aune team is a group of audiophiles who only pursue the best. We use our products in daily life and we love each and every one of them! Superb sound is Aune’s goal; great user experience and satisfaction is what Aune pursues. We are striving to make Aune one of the world’s famous audio brands in the future!
 
In order to design a world-class audio products, aune include the formation of an excellent R & D team of professional designers at home and abroad, has a number of strong, serious and responsible work of professional and technical personnel in our team, as well as a love for music professional audio career employees, 100 percent have a college, doctoral, master's degree or above. The most important thing is that they have strong technical strength, for the sound development of a range of products, from the cd drive, speakers, amplifiers, decoders, and even the future of the player home audio and video so you can design the perfect product, and can get the industry the affirmation and recognition of consumers!
 
LINK to Aune's English website.
LINK to the Aune M2 thread.
LINK to the Aune M2 US & Canada Tour thread.
 
 
DISCLAIMER
I was provided the M2 as a review sample and to kick off Aune's US tour for the M2 DAP + B1 2016 Version Amp. There is no financial incentive from Aune in writing this review. I am in no way affiliated with Aune, and this is my honest opinion of the M2.  I would like to thank Aune for sponsoring the tour and specifically @AuneAudio for allowing me to participate!
 
 
ABOUT ME
I'm a 43 year old father who loves music.  From electronic (Autechre, Boards of Canada) to modern/minimalist composition (John Cage, Philip Glass) to alternative rock (Flaming Lips, Radiohead) to jazz (John Coltrane and Miles Davis) to metal (Behemoth, King Diamond) to classic rock (Eagles, Rush), I listen to a wide variety of genres and artists. 
 
My portable music journey started with the venerable Sony Cassette Walkman and then progressed to portable CD players, minidisc recorders (still have my Sharp DR7), and finally on to DAPs like the Rio Karma, iRiver IHP-1xx, iPod 5.5, iPhones, and the newer crop of DAPs from Fiio and iBasso. 
 
I typically listen with IEMs from my ever-growing collection from budget to mid-fi. Less often, I grab a pair of full-size cans.  Recently, I've been listening a lot with my AKG K553 and HiFiMan HE400, as well as the Alpha & Delta AD01 and RHA T20 IEM I had in for testing.  I do have a lot of other gear, though.  You can always check my profile for a reasonably up to date gear list. 
 
As with a lot of people my age, I've got some hearing issues.  I've got mild tinnitus and suffer from allergies, which often affect hearing in my right ear.  I'll admit it, I'm not blessed with a pair of golden ears.  That said, I've been listening to portable gear for a long time and feel confident in assessing audio gear. I just wanted to be transparent up front. 
 
 
SPECIFICATIONS 
 

Headphone Out:	Output Impedance: 1Ω THN+N: 0.0009% @ 300Ω Peak power: 32Ω/230MW
Line Out:	THN+N: 0.00038% (24bit/44.1k 1KHZ 0DB) NOISE: 3UV DNR: 117DB CCIF: -118DB
Outputs:	3.5 mm Headphone, 3.5mm Line
Amplifier:	ARM + CPLD + AK4490 + High Bias amplification
Volume Control:	0-100, jog-dial controlled
Gain Selection:	Gain adjust adapts to headphones/earphones used
Equalization:	None
Storage:	1x micro-SD card (up to 128GB, FAT32), no internal storage
Supported Audio Formats:	DSD: DSF/DSD64, DFF/DSD64, ISO Whole Track WAV: 16/24/32 Bit, 44.1K/48K/88.2K/96K/176.4K/192K WAV+CUE FLAC: 16/24 Bit, 44.1K/48K/88.2K/96K/176.4K/192K APE, ALAC, AAC, MP3
Battery Capacity:	3500 MA
Battery Life:	7.5+ hours* (Class A, continuous play)
Charging Time:	4.5 hours at 800 MA (charger not provided)
Power Saving:	Auto Power Off, Backlight time off, Breakpoint Resume
Dimensions:	120mm x 65mm x 17.5mm
Weight:	195g

 
* Up from the 5-6 hours for pre-production M2.
 
Those are the base specifications for the M2, but there are three M2 variants with differences pointed out below.

1. M2 (US$349): 2x Japanese NDK 2520 ultra-low-jitter crystals. Black & Silver.
2. M2 Pro (US$499): 2x USA Crystek CCHD575 crystals, specially tuned OP-amp combination. Black & Silver.
3. M2s (US$649): Same as M2 Pro but with different colors, and Satellite-level, Teflon PCB substrate. Blue.

 
 
PACKAGING & ACCESSORIES
As this was a pre-production model, I didn't receive any packaging or accessories. @hakushondaimao has indicated that the final production models will come with packaging similar to Aune's B1 Amp. The only accessory you get is a USB cable to charge the M2. Basically, you're getting the a box with the M2 and a USB cable. No silicon cover. No storage pouch. Nada. At the price point we're looking at, I would've appreciated a silicon case. The M2 I've got is getting a few small dings, which a silicon case would prevent.
 
 
BUILD & ERGONOMICS
As usual, I'll go over the build and ergonomics in pictorial fashion below, pointing out what I like and what I think could be improved. 
 
FRONT + LEFT

 
Here we can see several features of the M2's physical user interface. The M2 has a nice all-aluminum case, which makes it quite durable but susceptible to dings, dents, and scratches. On the front face are three transport control buttons. I like these. They're in a pretty good spot for one-handed operation. When holding the M2 in my left hand, they're in just the right spot for my thumb to reach over and interact with them. Above those, you see the 2.4" IPS screen. Along the bottom you see the Headphone Out, Line Out, and micro USB charging port. No file transfer here, folks, so get out your card reader! All of the markings on the front face are laser engraved, so there won't be any worry about them fading over time. Markings on the other faces are painted on, and I haven't seen any degradation over the month or so I've been using the M2 despite the lack of case.
 
In addition to acting as transport controls, the Back/Forward buttons move up/down through menus. The Play/Pause button holds double-duty, both selecting menu items with a press and backing out of menus with a press + hold. A quick press + hold backs you out one level, while a longer press + hold takes you back to either the Main Menu or Now Playing Screen. It's a bit unusual, but you'll get the hang of it quickly. I've also got a video below that shows the UI in action. Press Back + Play/Pause to switch between Play Modes. Press Forward + Play/Pause to Add/Remove a song from Favorites.
 
And the color is very tricky to capture. It's more of a teal blue. I was going to include a pic from Aune's website, but even their press images of the blue M2 don't capture the color properly. Oh well, you'll just have to use your imagination...
 
 
REAR + RIGHT

 
The usual info is on the back. Being a pre-production model, this one got the SN001 serial number. Along the left side, you see the reset hole (gotta look carefully for this one!), the sole micro SD card slot, the rotary dial, and the micro HDMI port. Similar to the transport control buttons, the dial does double-duty as both volume controls and menu navigation. If you're on the Now Playing screen, a press takes you to the Main Menu, which a press + hold backs you out to the song list. In menus, a press selects items, which a press + hold backs you out a level. A long press + hold backs out to the Main Menu and then back to the Now Playing screen. Again, it's not quite like other UI I've used before, but you'll get the hang of it quickly enough. And it's fast, which is nice!
 
​Edges along the rear side are just slightly rounded. I wish they were more rounded like the front edges, as the edges tend to dig into your palm. If you get a chance to audition the M2, turn it over in your palm and feel how much better the nice rounded front edges feel in your hand. Hopefully next time...
 
 
BOTTOM & TOP EDGES

 
Bottom: HO, LO, micro-USB
Top: Power / Screen Lock Button
 
 
RIGHT & LEFT EDGES

 
Right: Reset hole, micro-SD slot, Rotary Dial, Micro-HDMI
Left: Nada, nothing, zilch...
 
Okay, so we've been all around the M2 now. You've seen it all. What did I like? I really like the button layout. It's very well thought out for one-handed operation in the left hand, so you lefties should be happy with this DAP. Your thumb controls the three buttons on the front, your index finger gets the lock key, and your middle finger gets the rotary dial. Very easy to use with minimal shifting in your hand. Nice! What was missing? The most obvious to me was the lack of COAX / SPDIF Out. You've got micro-HDMI, which you could use to connect up to a home system but not the more typical Coax Out. This means you're not going to be connecting the M2 to any portable DAC/Amps any time soon. I'm not up on whether micro-HDMI is being implemented in desktop DAC/Amps yet, but I haven't seen it. You can always get an HDMI → COAX converter, but then you're adding more circuitry to your audio chain. Main point, the Digital Out choice is unusual and somewhat limiting at this point in time. I think Aune is very confident you'll be happy with the M2's performance and won't be looking to use an external DAC/Amp.
 
 
I didn't include a comparison pic, but the M2 is basically the same dimensions as the FiiO X5. M2 is just a hair narrower and about a cm shorter. This puts it right between the FiiO X5 and Shanling M3. In other words, it's getting up there in size and is more on the transportable size. It's the sort of DAP I like to throw in my "man bag" instead of my jeans. Shirt pocket? No way. Skinny jeans fan? Nope. Go get yourself a nice "man purse"! 
 
And again, Aune decided to make this nifty BLUE color exclusive to the top-level M2s DAP, so you'll be looking at Black or Silver for the M2 and M2Pro.
 
 
GUI / FIRMWARE
As I mentioned in the introduction, I've been through several beta versions of the firmware and am now on the final version. What a wild ride it's been, my friends. Fun, though. I've been a beta tester before, so I enjoy the experience of working with engineers and developers to fine-tune the user experience. Of course, the manufacturer has their own vision and definitely has the final word, so some of my suggestions weren't included in the M2's feature set. That's okay. Aune definitely had a vision for the M2, and they stuck with it. What I'll do now is give you some pics of the GUI and also include a video where I go over the physical and software UI to help make things clearer.
 
Before we begin, though, I want to make one point clear. The M2's GUI was built for speed. This isn't a luxury car approach. The M2 is like a sports car tat's been intentionally stripped down for maximum speed. It boots so fast, it's almost like the hibernation mode on other DAPs. Push a button, and the M2 gives you what you want and it gives it to you right now. I think it's the most responsive DAP I've used, and I have little doubt it's because it's so stripped down. It's also rock solid. Sure, I've encountered some bugs. I haven't had it freeze, though. The reset hole has not been touched by me. Not once. Nice!
 
MAIN MENU: SONGS + FOLDERS
→
 
On the top row, you see the Songs menu item. This is basically a list of all songs on your M2. Select this, switch to shuffle mode, and you've got your own Shuffle All radio station.
On the bottom row, you see the Folders menu item. This is probably where you'll spend more of your time, so please organize your mSD card. I like Artist → Year  Album → Songs. Adding Year ensures all of my albums are ordered by release date. This type of organization can be easily automated via MP3Tag + Google-Fu and is well worth it for any DAP, IMHO!
 
 
MAIN MENU: PLAYLISTS

 
Here you get two choices. Most played just gives you a running list of your most played songs. Favorites gives you a chronological list of all the songs you've favorited.
 
 
MAIN MENU: SETTINGS

 
I'm not going to go over all the settings here, but I'll point out a few interesting points. First, I really like the Lock Key Setting. You can customize which buttons are active while the screen is locked. Same goes for the rotary dial. Some of the buttons and rotary dial functions even have more than one choice. This really allows you to make the Aune M2 work the way you want it to when the screen is locked. Nice!
 
Nitpick time... See that Gapless Playback choice? Well, it only works if you've got a CUE sheet. That's probably my biggest complaint about the M2, and one I've made very clear to Aune more than once. Play Mode toggles between Folder Repeat, Folder Shuffle, and Song Repeat. I've requested a Play Mode that just plays the current folder once and stops. I don't know about you, but I dot need to hear the same album ad infinitum. A "play through folders" feature would also be appreciated. Totally missing is a choice for Resume Play. The M2 always starts up at the beginning of the last song you played. I'd like the choice between beginning vs. position. Hopefully some of this missing functionality will be added in over time.
 
 
NOW PLAYING

 
Whew, we've finally made it to the Now Playing screen! On the top bar, you get a volume indicator which maxes out at 100, a lot of blank space, DAC filter indicator, an empty spot for the ♡ Favorites symbol, Play/Pause + Back/Forward indicator, Play Mode indicator, and finally the battery indicator. In the main screen, you get Song, Artist, and Album from top to bottom. Song name is derived from the file name, while Artist and Album are derived from tags. At the bottom, you have the elapsed time, song # / # songs queued up, and song length above the progress bar. Under the progress bar, you have resolution, bit depth, and file type. No album art, though. Hope you didn't want any. Doesn't bother me one bit. I'm here for the music, not to waste battery life looking at pretty pictures. Of course, YMMV.
 
Aune's Quick Start Pic should help:
 

 
 
HW + FW UI VIDEO

 
TO SUM UP
The M2's GUI is pretty bare bones, so be prepared for that going in. Don't expect a lot of frills, keep your files / folders well-organized, and you'll be fine. in fact, you'll be treated to a very fast GUI! Of course, it is missing some common features other DAPs have. So if you're looking for non-CUE sheet gapless playback, EQ, album art, tag-based browsing, etc., you're going to be sorely disappointed. If that's you, move along, my friend!
 
 
BATTERY LIFE

Battery life is on the short side for a DAP these days. You're looking at DX90 level battery, so in the 5-6 hour range. I'd heard rumblings of better battery life in the 8-9 hour range for the final production model, but this doesn't seem to have played itself out yet. Hopefully battery life can be optimized with future firmware updates. Be prepared to top the battery off every day or two, depending on how much you plan on using the M2.
 
 
USB DAC

USB DAC? What USB DAC? Move right along, good sir!
 
 
SOUND

During my time with the M2, I've had the chance to play around with the Empire Ears IEM lineup, FLC 8S tunable triple hybrid IEM, HiFiMan Edition X planar headphones, and VE Zen 2.0 earbuds. As usual, I listened mainly to classic rock, electronic, metal, and modern composition in AAC and FLAC formats. I also had the Chord Mojo and Soundaware M1 Esther Analog in for testing at the same time, so I put in some time switching off between these three sources and have some thoughts on what the strengths of each are. 
 
In general, I found the M2 has a very dynamic sound just on the warm side of neutral with a wide soundstage. It easily competes with other DAPs in its price class and beyond. To illustrate that, I chose to focus on M2 vs. Mojo and Esther Analog, which are both around twice the price of the M2.
 
Warmth: Esther Analog >> Mojo > M2
Fullness: Esther Analog >> Mojo > M2
Dynamics: M2 > Mojo ≃ Esther Analog
Soundstage: M2 > Mojo ≃ Esther Analog
3D: Mojo ≃ Esther Analog > M2
Bass: M2 > Mojo ≃ Esther Analog
 
Mids: Esther Analog > Mojo > M2
Treble: M2 > Mojo ≃ Esther Analog
 
Mojo and Esther Analog are very impressive sources. Very impressive! I was quite surprised at how competitive the M2's sound was. Listening to M2 on it's own, it's easy to get swept away by the sound. Listening in comparison to Mojo and Esther Analog, M2's bass sounds a bit enhanced, the soundstage is wider but not as 3D, mids aren't as full and sweet especially when compared to Esther Analog. I'd say which you prefer comes down to preference, as I didn't feel I was missing out with any of them. I was just getting different flavors.
 
VOLUME @ COMFORTABLE LISTENING LEVEL
FLC 8S: 40/100
Empire Ears Zeus: 25/100
VE Zen 2.0: 50/100
HiFiMan HE400: 50/100
HiFiMan Edition X: 45/100
 
M2 drives everything from extremely sensitive IEM to power-hungry planars well. Even though I got plenty of volume out of the M2 with HE400 and Edition X, I did find stacking them with the Aune B1 Amp in Class A mode made them a bit punchier. it certainly wasn't necessary, but I had the B1 at hand so why not.
 
Not my HE400, but you get the picture. The M2 + B1 stack was obviously meant to be!

 
 
SUMMARY

What an interesting experience this has been. The M2 is probably the most unique DAP I've tried. Unlike the other DAPs I've tried, the M2 eschews most creature comforts for the sake of speed and simplicity. So-so battery life, no album art, no tag-based browsing, no gapless unless you generate CUE sheets. It's certainly not a DAP for the everyman. It's a DAP for the hardcore audiophile who gladly makes those trade offs for the sake of a very dynamic, engaging sound, Class A power, and nicely engineered ergonomics. If you feel you need a little extra oomph, hook it up to the Aune B1 and you've got a very synergistic combination. Are the trade-offs worth it? For me, they're not really trade-offs. I intentionally strip album art out of albums on some of my DAPs to speed up the UI, so obviously the M2's lack of album art support doesn't impact me much. I also have a very organized folder structure on my mSD cards and rely solely on Folder Browsing, so again no compromise for me. I'm rarely without access to power, as I typically keep an external battery pack and cables in my man bag when I'm away for the day. Gapless, though. That one gives me some grief. I'm really hoping Aune is able to enable gapless without the need for CUE sheets. I also hope they enable positional resume so I'm not forced to start at the beginning of my last song every time the M2 starts up. And finally, I'm hoping they add in play through folders and single folder Play Modes. If Aune implements these last three (gapless, positional resume, and additional play modes), I'd be thoroughly satisfied with the M2 and bump up it's rating to 4.5 stars. I know some of you love your creature comforts, though. For you, I'd give the M2 a 3-35. star rating depending on how strongly you feel you need all those first-world comforts the M2 is missing. In fact, a lot of you will probably see the lack of album art and tag-based browsing and move on. That's too bad. The M2 is a finely engineered music machine that deserves more attention than I think it'll get. Hopefully this review helps.
 
Thanks for taking the time to read this. Feel free to shoot me a PM if you've got any questions. 
 
And finally, a big thanks to Aune and @AuneAudio for providing me with the M2 for review and for setting up the M2 + B1 review tour. They're both great products, and I look forward to seeing more great products from Aune in the future. If you've read this far and are interested in the tour, please check out the following LINK!

I’ve participated in a couple of review tours for Aune products (the B1 portable headphone amplifier and the X1S desktop DAC) in the last several months, and really enjoy the clean, neutral Aune house sound (or at least what I believe to be their house sound, based on limited exposure).
 

 
In early October, having seen several posts and reports of the upcoming M2 DAP, I took a chance and asked if there was any chance of a review unit. As luck would have it, Aune was just wrapping up development of the hardware at that time, and they asked me if I’d like to help troubleshoot and beta test the software. I jumped at the chance, and a couple of weeks later was in possession of a lovely blue (BLUE!) pre-production base-model M2. A few weeks later I received a second M2 (pre-production Pro model this time) as a sample for a Head-Fi meet I organized in Calgary, and to send out on tour once firmware development nears completion.
 
There are three different versions of the M2, as follows:

1. M2 (US$349): The “standard” model, with 2x Japanese NDK 2520 ultra-low-jitter crystals.
2. M2 Pro (US$499): With 2x USA Crystek CCHD575 crystals, specially tuned OP-amp combination.
3. M2s (US$649): Upgrade of M2 Pro. Same spec as M2 Pro, but with different colors, and Satellite-level, Teflon PCB substrate.

 
Base model M2 (Blue) and M2 Pro (Black)
 

 
Over the course of the last couple of months I’ve listened to both M2 units quite a lot, and have seen the firmware go through around 10 iterations, with improvements each time. One thing that has remained constant it the sound quality of the device, which in my opinion is excellent.
 
Disclaimer: While I have assisted Aune in refining the M2 firmware, I am not affiliated with the company and have not benefitted monetarily from my participation in any way. This review represents my honest, independent opinions about the M2.
 
 
The Aune M2
 
Let’s dive into the review with physical attributes and specifications.
 
Unboxing & Design
 
The M2 comes in an understated yet sturdy dark blue cardboard box, similar to the one that for the B1 amp. That makes sense as the two have almost identical dimensions. The first M2 I received came sans accessories, and the second (the M2 Pro) came with a USB-micro USB cable for charging.
 
The M2 itself is a conservative looking digital player, with a chassis constructed from hollowed 6-axis aircraft aluminum. The anodized face-plate has a brushed metal look, with laser-engraved text, and other surfaces are a matte-finished metal. The first M2 I received has rather sharp edges (this one seemed more of a prototype) while the M2 Pro edges are less sharp (though I’d prefer a bit more curve).
 
     
 
Taking a tour of the M2 externals we find:
 

1. Front: As mentioned, a brushed metal surface with matte bevelled edges. At the top end of the unit the word “aune” is etched into the surface, and at the bottom “M2 32Bit DSD Music Player.” The 2.4” IPS display takes up most of the top half of the unit, and below the screen are three buttons: Back, Play/Pause/Select, and Forward.

 
          
 

1. Rear: The back of the M2 is flat, with a matte finish. There is no functionality here. The brand, model and serial number appear, and I would assume there will be additional standards information on production units.

 
          
 

1. Top End: Looked at from above, we see the power button on the left. A long push turns the unit on and off, while a short push turns the screen off and on during use.

 
          
 

1. Bottom end: Looked at from below, from left to right we have the 3.5mm headphone out jack, 3.5mm line-out jack, and micro-USB charging jack. This jack does not double as a sync port.

 
          
 

1. Left side: The left side has no controls or design elements.

 
          
 

1. Right side: Looked at from the right, we see from left to right a reset control opening (use pin or paper clip), TF slot (micro SD, 128 GB supported), jog dial for volume control (and back/forward control when screen locked), and a multi-function expansion port (with rubber port cover). The jog dial is etched with a grid pattern to provide texture and grip when turning; however, the etching is quite fine, so it’s easy to slip when adjusting the dial (I’d prefer a slightly coarser, rougher etching for better grip and sense of control). The multi-function, Mini HDMI expansion port doesn’t currently do anything; functionality will be added in future for both data transfer and digital output.

 
          
 
Selected Specifications:
 
 
* The pre-production unit I tested was rated at 6.5 hours battery life. I've been informed by Aune that this has been increased to 7.5 hours+ (Dec. 8, 2015)
 
My Experience with the M2
 
The M2 has what is (to me) an unusual arrangement of controls. I’m most familiar with the Fiio DAPs (X3ii and X5ii), which I find quite intuitive and easy to operate, and have also had experience with the Hidizs AP100 (controls sometimes screw with my head), Cayin N5 (intuitive), Shanling M2 (intuitive), and Cayin N6 (confusing physical user interface).
 
It didn’t take long to get used to the Aune M2 controls, and I found the uncomplicated system relatively easy to navigate. I find the UIs used by Fiio, Cayin and Shanling very similar, and indeed I’ve read that they share common base programming. The M2 software is clearly built from the ground up, and is also a work in progress. The system is common to the Aune desktop X5S and S18 audio transports, and I imagine as one item’s software evolves, so too will the others.
 
My only real issue with the UI was sometimes pushing a button or the dial (particularly the dial) a little longer than I should have for a short push, or a little shorter than required for a long one, and so making a move I hadn’t intended. The Quick Start graphic below explains pretty well the different button and dial controls and combinations for various functionality.
 

 
As mentioned, the M2 firmware is pretty basic. This makes it easy to navigate, but also means that features available with other players are not available (I’ll deal with that shortly). The home screen is laid out simply, with 4 icons showing the buckets of features as follows:
 

1. Songs: Play songs. All your songs. Set the player to random play and let rip.
2. Folders: As with most other players, folder browsing by Artist > Album > Song (or however the user has their folders laid out).
3. Playlists: Most Played (player defined) and Favorites (user defined).
4. Settings: Controls for start-up auto-play (on/off), play mode (folder, shuffle, repeat), filter mode (Sharp SD, Sharp LD, Slow SD, Slow LD), backlight brightness (1-7), auto power off timer, backlight timer, gapless play (on/off), operation tips (on for newbie, off once you’re a seasoned user and know the controls), language (Chinese, Simplified Chinese or English), settings restore, system upgrade (or update), system info and lock setting (control functions for buttons and jog dial when screen is locked).

 
          
 
In terms of features, the M2 is pretty bare-bones compared to some of the other digital audio players in the same price category (like the Fiio X5ii and Cayin N5). It seems Aune have decided to keep things clean and simple, and focus attention on audio quality. My observations on M2 functionality include:
 

1. Deep sleep/hibernation/deep standby mode: While there is no hibernation function, the M2 boots extremely quickly (due I’m sure to the very simple software). With a quick boot (less than a couple of seconds?) and starting up at the last song played before powering down, a deep sleep feature, though “missing,” is forgiveable.

 

1. Protective case: I think every DAP should come with some kind of case or pouch, especially when you get into the $250+ range. The M2 doesn’t have a case, which to me is a shame. Even a simple silicon slip-on cover would help protect one’s M2 investment from nicks and scratches.

 

1. USB connection to PC for data transfer: At the moment there is no way to connect the M2 to a PC to load music as the Micro USB port is only for charging and the expansion port is purely cosmetic (for now). Not a huge deal as I just removed the micro SD card whenever I wanted to load new music or make other library changes (this is how I do it even when USB data transfer IS possible as it’s faster).

 

1. External DAC: The M2 can’t be used as an external DAC. For a portable device, that’s a shame. When I’m on the road (which is frequently) I like to pack a portable DAC for use with my laptop for movies or Netflix, but I’d prefer not to have to pack two devices (DAP and DAC). I can imagine gamers might also appreciate being able to use the M2 as a DAC. Considering the quality of sound coming from the M2, it’s a real shame that DAC functionality isn’t included.

 

1. Coaxial Out: The M2 is clearly designed as a small-format, all-in-one audio device. There is currently no digital output with the M2. The product literature states, “With… multi-format support and superb reproduction of the original live event/recording sessions, the M2 is your mobile concert hall that liberates you from the large-size HiFi system.” For my purposes, the lack of Coax is not a huge deal as the quality of sound coming from the device is very good, and I’m quite happy to connect to an external amp (like the B1) via line out, if and when necessary. For anyone wanting to use the M2 purely as a transport and hook up digitally to a desktop DAC, that isn’t an option at the moment (though that will change when software is developed further and the expansion port goes live).  EDIT (Dec. 8, 2015) Aune are currently working on an external docking connect through the Mini HDMI port, which will bring digital output capabilities (Coax, AES, I2S, etc.) via a receiver module to high end DAC.

 
               
 

1. Playlists and browsing categories: As mentioned already, playlist support is limited to favorites (tracks can be added and deleted by the user), most played, and all tracks. There doesn’t appear to be support for multiple playlists, or for imported lists. Browse by artist, genre, composer, etc. is also not currently supported.

 

1. Album Cover Art: This is another feature that is not yet supported, and it’s not clear whether it will be at some point in the future. Would be nice to have, but as with other features may be a required sacrifice/compromise in the interest of sound quality.

 

1. Support for all music formats: Product literature lists most of the commonly supported music formats as supported. I used a variety of source files during my testing, and while most of them played fine, I did run into some issues. I had no problems with DSD and FLAC files, which sounded superb. I did have issues with AAC and ALAC files, however. With the latest firmware I tested (FW 1.10), both AAC (256 kbps and 320 kbps) and Apple Lossless tracks would only play if they were shorter than 7’30”. Longer tracks were skipped, which meant I was unable to listen to most classical and a lot of my jazz and ‘70s prog-rock tracks. For the tracks that did play, sound quality was excellent, but occasionally songs would stop playing midway through and the player would skip to the next song. For a Mac+iTunes user, this means some music will be unplayable, unless music files are converted to MP3 or FLAC, resulting in added complication of conversion tools, a non-iTunes media player, and otherwise unnecessary usage of hard drive space.

 

1. Gapless playback: This feature is listed in product literature as supported, but currently warrants an asterisk as it is limited to single-file albums with CUE. Most of my music consists of album folders containing individual files for each track, and in this set-up, gapless does not work. I am told that full gapless support is being worked on for future firmware releases, but for now this again means an added complication of file and format conversions.

 

1. Equalizer: There is no equalizer control available. I don’t as a rule use EQ, so for me this is not a big miss, but for those who do it could be a deal-breaker.

 

1. Battery: The M2 is rated at 6.5 hours of playing time, which is on the short side. I didn’t test this carefully, but I did feel the battery ran out rather quickly compared to my other DAPs. The M2 does get warm during extended use (though not overly so), so it’s clearly using some juice!  EDIT (Dec. 8, 2015) Aune states that the M2 is Class A music player, with voltage greater than 500MA, and that a compromise had to be made between a Class A/B device with 8 hours of playing time, and Class A with 6.5hours. The decision was made to sacrifice playing time for better sound quality. With daily charging, 6.5 hours battery life should be enough for regular use, and external power packs can be used to extend this if necessary. Several hours later I got another another update saying that the battery life on the production models has been upped to 7.5+ hours. Not clear yet if that's a FW tweak, or if they've done something with hardware.

 
The M2 Sound
 
If it seemed I was dissatisfied with the M2 as a product at this stage, I wouldn’t be surprised and you’d be forgiven for thinking so. While there are deficiencies in comparison to some other popular, more full-functioned DAPS, and I eagerly await introduction of and improvement on features listed as “supported,” I can say that I am willing to forgive some of my gripes purely on the basis of sound quality. I very much like the sound of the Aune M2 and that’s what I’ll look at next.
 

 
Overall I find the M2 has great balance, detail and texture. It’s sonically revealing and has a quite neutral character.
 

1. Bass: Bass goes low, has good slam and dynamics, nice reverb and ambience. Speed is excellent, as is bass definition. Sub-bass is present, but not as deep as some other DAPs.

 

1. Mids and Highs: Neither forward nor recessed, detailed and layered, clear, good extension and no issues with sibilance. Balance well with bass for even, natural presentation.

 

1. Vocals: As with mids and highs, M2 is revealing of texture in vocals. Micro detail of vocal signatures portrayed accurately and articulately. Both male and female vocals shone in their balance with rest of music.

 

1. Filters: The M2 has four DAC filter settings: Sharp SD (short decay), Sharp LD (long decay), Slow SD, and Slow LD. I didn’t play around with the filter settings too much, but was able to hear differences, particularly between Sharp SD (drier, more detailed) and Slow LD (warmer, fuller). Most of my listening and all of my comparisons to other DAPs was done with the Sharp SD filter engaged.

 

1. Detail: Definition of individual instruments and voices is excellent, with tight, textured detail and layering. Excellent clarity, no muddiness or bleed in complex, energetic pieces or passages. Transients are well defined from bass through treble, verging on dryness without being dry (with subtle warmth added with Slow LD filter).

 

1. Soundstage and Imaging: I find soundstage depends a lot on the headphones or IEMs used, but the M2 has a good sense of space and depth and accurate positioning. Switching filters allows for some control here, with Sharp SD filter giving a drier presentation with less ambience, and Slow LD warmer and more atmospheric.

 

1. Hiss: I didn’t notice any hiss with the IEMs I used. Background is nice and dark.

 

1. Power: When I first started playing with the M2, I was a bit concerned about its power handling capabilities as even with relatively sensitive IEMs I had the volume set to around half way (45-55/100 depending on IEM). You’ll notice in the spec’s that “gain adjust adapts to headphones/earphones used,” and I was pleasantly surprised to find that the M2 was able to drive quite powerful headphones with some authority. I tried the M2 out with my 470-ohm Audio Technica R70x and my AKG K7XX, in addition to loaner ZMF Omni I’ve been enjoying for a while, and with all three I got decent volume and sound quality (though the R70x sounded just a tad thin, and with all I had to push the volume up to 100/100). Adding and stacking with the very capable Aune B1 portable amp (see @nmatheis' excellent review of the updated 2016 edition here) took things to another level, and this is a combination I highly recommend.

 
               
 
Sound Comparisons with Other DAPs
 
I compared the M2 and M2 Pro to a number of players, from the affordable but capable Shanling M2 through mid-tier Fiio X5ii and Cayin N5, and on to higher end Fiio X7 and Cayin N6. Comparisons were performed using my handy Line5 headphone output switcher, which allows me to volume match, synchronize music on two DAPs, and then switch back and forth while playing without having to unplug and/or plug anything in. Instant switching while tracks continue to play allows easier identification of sound differences as there’s virtually no memory lag to deal with.
 

 
One of the things I’ve noticed as I experience a range of audio equipment is that sound differences between DAPs are far more subtle than between headphones and amplifiers, particularly within a given price tier. Quality across the board is becoming better and better, and often differences will only become apparent with focused listening.
 
Another note about sound comparisons described is that less or more of something isn’t necessarily a bad thing. DAP-A could have more or better sub-bass, for example, but that doesn't mean DAP-B’s sub-bass is poor. So take the comparisons with a grain of salt.
 

 
For non-sonic differences, all the DAPs I compared can be used as external DACs, have digital out, and offer gapless functionality and ALAC/AAC support. I won’t spend any more time on differences in feature sets, but sonically here’s a summary of how various models stacked up (detailed listening notes appear after the summaries):
 

1. Aune M2 (base model) vs. Aune M2 Pro: Both are engaging, with balance, detail, texture. Sonically revealing and neutral. The Pro has a hard-to-define, subtle lustre to its sound that is missing in the base model. Pro is very slightly bigger sounding, dynamic range and instrumental clarity just a hair enhanced, but other than that everything is the same.

 
          
 

1. Aune M2 (base model) vs. Cayin N5: I didn’t have a lot of time to compare these two as the M2 came in on the same day I shipped out the N5 to the next participant in that review tour. I found the M2 bass attack marginally quicker than N5, and sub-bass a touch deeper. Shorter decay in mids and highs gives better definition to notes and instruments. Vocals are cleaner, more textured and detailed With N5, bass softer-edged with longer decay, adding body and feeling of space. Longer decay in mids and highs adds ambience and contributes to warmer presentation.

 

1. Aune M2 Pro vs. FiiO X5ii: M2 transients quicker, leading and trailing edges of sounds clearer. Bass less prominent, mids and highs more forward. Vocals brighter, more detailed, layered and textured. X5ii bass rounder, deeper sub-bass, more reverb, more impactful than M2. Mids comparatively recessed. M2 better balanced across frequencies; with X5ii bass dominated overall presentation.

 
          
 

1. Aune M2 Pro vs. Cayin N6: M2 Pro is definitely at N6 level SQ-wise, though slightly warmer. Decay on bass and mids fractionally longer, giving fuller, more ambient atmosphere. N6 not dry, but drier. M2 Pro not warm, but warmer. Marginal differences. No real preference, but taking price into account have to say M2 Pro represents better value.

 

1. Aune M2 Pro vs. Shanling M2: Shanling M2 is lower key, shy but capable. Doesn’t draw attention, but neutral clarity and balance. Aune M2 Pro weightier and meatier, fuller. Bass tighter, deeper, greater impact… more present but not forward. More dynamic and extroverted, greater extension, warmer (but still not warm).

 

1. Aune M2 Pro vs. Fiio X7: M2 Pro subtly cleaner and more detailed. Bass depth similar to X7, but quicker, less reverb and more plucky entry. Mids and highs very similar to both in extension and detail. M2 Pro slightly less warm, tighter and more detailed in mids. Differences are quite minimal and, to me, focused on the bass end. While sonically similar, the X7 boasts numerous features not shared by the M2 in addition to the ones mentioned already, including touch screen, wireless and streaming (albeit at a higher price).

 
 
 
Conclusions
 
It should be clear by now that I really like the way the Aune M2 sounds (both base and Pro models, but particularly the Pro). I feel it outclasses most of the other DAPs I compared it to, particularly in speed (transients, in bass particularly but throughout the spectrum), and detail, texture and layering. I’d place the M2 (Pro anyways) at a similar level as the Cayin N6 in sound quality.
 

 
While there’s much to praise with the sound of the M2, I feel it’s very much still a work in progress. Some functions that are standard in most other DAPs have been left out, or are still under development. The main unresolved issues and missing features include:

1. ALAC and AAC playback not supported: Longer songs won’t play, and there can be random instances where a song just stops and the player skips to the next one (for some reasons, the M2 doesn’t like my ALAC rip of Fleetwood Mac’s “Rumours.”) To me, this makes the M2 an unsuitable DAP for anyone using iTunes as a primary music source (on PC or Mac) as converting song files to FLAC or MP3 is inconvenient and overly complicated. Aune tells me ALAC and AAC are being worked on, so this is an issue that may be resolved in future FW updates.
2. Limited gapless support: Gapless works a treat, IF you’re using CUE files with an entire album ripped to a single sound file. If, like me, you rip songs to individual files and place them in an album folder, gapless won’t work. I tested this with DSD, FLAC and ALAC, and all of them had gaps between songs. Word from Aune is that this issue will be addressed.
3. No digital in or out: If you’re looking to use the M2 as an external DAC, it can’t be done. If you want to use it as a digital transport hooked up to another DAC, you’re also out of luck (for now). The expansion Mini HDMI port was included to provide digital transfer capabilities in the future, via some sort of docking station or receiver module, but what that will be like is currently unclear.
4. Limited playlist support: Playlists are limited to favourites, most played, all songs, and albums (via folder browsing). Tagged browsing (by artist, composer, genre, etc.) is not supported, though could easily be implemented.

 
As it stands, the M2 represents a superb DAP for a user with these criteria: 1) All music is in DSD, FLAC or MP3 format, 2) gapless albums use CUE files, 3) uses folder browsing only, and 4) has no need to connect a DAP digitally to other equipment.
 

 
For anyone else, the M2 is a DAP to watch and consider as issues are resolved and functionality is added. I for one WILL be watching as I see the M2 as a DAP with huge potential, and will return to edit this review (hopefully with pluses) as the M2 develops and improves.
 
My thanks to Aune for the opportunity to try out the M2 (both base and “Pro” models), and provide input during pre-production development. Thanks for reading, and I hope my feedback has been helpful.