Pros - Beautifully Clean, detailed, warm and elegant sound, excellent details in ALL frequencies range, Line out, Changeable battery, good construction...
Cons - Poor battery life (extra battery needed), Unstable firmware that can cause serious problem to the player, vain equalizer
It make more than 1 year that I listen daily to my beloved Ibasso Dx90 and I feel it's now time to make a proper review of this wonderful DAP.
To begin, I have in my possession this audio players in the past - ihifi 812V2, Colorfly C3, Hifiman H601 and Fiio X3- and the Ibasso is the only one I kept. It say alot I think, because the only one DAP that I regret selling is the Xuelin ihifi 812V2 and it's because of his wonderful warm Wolfson sound that is extremely different to the Ibasso Dx90 wich is more coldish-warmish and analytical sounding.
The Dx90 is well built, all black brushed metal alloy with 3 big button and that's it. When my girlfriend see it she say : ''How ugly, this player look like to have been built for man only''. Well, i'm a man and find it very beautiful, it is sober, classy and dark, very dark, all black and not sensual or playfull in his look. This player look serious and sound serious. And it have it all : 3 amp gain switch, one coaxial out and one line out, volume button at the right side and on-off button at the left side, changeable battery, a micro SD slot and the most important : a touch screen.
As said, physical fonctionality is quite minimalist, when the screen is close you can't use the touch screen so with the 3 big button you skip tracks or pause it easily from your pocket without having to look or pull out the player. The touch screen interface is fast and easy and firmware is quite stable but there is a LOT of them, wich can be confusing as must of firmwares have different sound signature (will talk about this later). So, you have lot of options in this little device, but this isn't an Ipod and some Ipod user did not like the ''folder'' based interface. As I listen to full album and i'm not a mix guy, this wasn't a problem for me, but I think it's better to use Flac files than Alac (mp4a) because some user have problem with tagging. Anyway, you can create playlist in your folder or inside the Dx90 easily, choose your music by directory, album, artist or genre and choose inside memory folder or micro sd card folder. Touch screen is very responsive and scrolling go well but displaying is very SMALL so it can be frustrating for people with big finger, especially taking the fact that must of time it's the thumb you use to navigate.
10 firmwares. Plus lot of non official ones that worth the try. Firmware aren't suppose to affect the sound ''theoretically'', but even Ibasso confirm that it does make subtle change. I try them all and return to the V2.1.5 everytime (lurk version). I will say the sound signature is always similar but Low and High can change a little as well as instruments separation and ''air'' between sounds. As I feel other can sound too bright and bass shy, I sadly return to my favorite one even if it doesn't support DAC option for MAC. The 2 last versions can handle this tough, but the last firmware DAC option do not work well with my Amarra Symphony software and make clipping-static noise, I don't investigate more about this as I have other DAC and did not really care about the one of Ibasso Dx90 (I like to have different sounding source). What I care about is sound, usability and stability, and from firmware 2.1.5 to 2.4 I do not have real bugs to report with the kind of use I have. Sometime when a track change their can be a little click noise, as well as when you close the device. Something strange too is that you have to take out the battery and put it back because the player will not start for unknown reason, this can be frustrating and frightening but it happen twice in a year for me. If you do not scan you micro sd card before, sometime the album will not play fully and you will have to skip the track yourself to it to play fully again. That's about all the ''bugs'' I can find and it's perhaps due to the fact that I change firmware LOT of time and install unofficial ones too.
For review I use :
Headphones : Grado Sr325i, Koss Portapro, Sennheiser HD480
Earphones : Westone custom Es20, Yamaha EPH-100, Xiaomi Pistons 2, Brainwavz R3
Amplifier : Fiio E7, Sansui AU-D5
Firmware : V2.1.5L
Music Format : 16-24bit Flac 44-96Khz, Mp3 320kb, Wav
Music genre : Classical (chamber quartets), Jazz (Ecm, post-bop, fusion), IDM, Indie (female signers), Folk (Female signers), Ambient (with lot of sounds layers)
As I said, I find that firmware does change the sound, not drastically, but it can push a little foward the bass with some. I said that because the Ibasso Dx90 have not a big bass impact or let's say tweaked low end, it is a neutral player that treat all frequency range equally. The extension and clearness is excellent and go deep, very deep. Decay in bass is superb, toms kick blossom in space, sub bass go well beyond hearing possible perception. The imaging of low are fabulous too and do not blur other frequencies ever, it is extremely precise and you can heard every bass line perfectly even trough big orchestra. To complement well this player, headphones with a good amount of bass impact can really make a difference. For example, I find the Yamaha EPH-100 (a bright earphones with average soundstage) to sound dry and boring with bass heavy music and that even if with some track it can exceed to render the finest details of a bass line. With the Xiaomi Pistons2 it complement superbly and make this 15$ earphones sound like a 100$ with a round, bassy and detailed sound. The Grado Sr325 complement well too, but not with electro music. Koss Portapro are a superb combination that have a very exciting sound with fast punchy bass, every Ibasso Dx90 owner should have a pair of these, the extreme clarity of Ibasso sound make an absolute duo with the somewhat dark sound of Portapro. In other words, Ibasso Dx90 have a studio like bass presentation of very detailed clarity, it is not a sensasionalist presentation, more a perfectionist one.
If I describe the Ibasso sound as a U shape one it isn't exactly what I heard but it's near, as a very neutral and clean player the mids do not need to be overemphasized to be enjoy. There a feeling of liquid easyness with the whole sounds layers that permit to concentrate on your favorite part of audio spectrum and pick every bit of details you want. The vocal with Ibasso are bright and superbly articulated, never the voice feel unatural or sibilant, it will be the fault of your earphones-headphones if it does. With the Yamaha EPH100 it can make sibilance and the mids are tweaked in a very bright way, with the xiaomi it help the V shaped sound to feel more articulated and hear more easily the mids without any sibilance. With the Grado Sr325i vocal are push a little foward as well and result in a harmonious and detailed whole. I find the mids even better with an amp trough the line out, especially a big one as it give a little warm to the somewhat serious sound of Dx90. What is exciting with a player that have a line out is the freedom of changing slightly the sound the way you prefer, with a line out you have a reason to make a amp collection. If I compare the Sabre ES9018 dac to the Wolfson WM8740 of the Fiio E7, I will say it's digital world versus analogue world, sacd versus vinyl, OP amp versus tube amp, purity versus musicality, hope you get what I mean. Medium frequency are more rounded and foward with Wolfson than Sabre, more easy listening type, and I admit that straight out of the DAP the Xuelin ihifi V812v2 can give more goosebumps with vocals in general, but if you use an amp with Ibasso Dx90 the story change as well as the details retrieval are way out of the Xuelin league. So, another time it's up to your personal taste, but I feel Dx90 sound is more an all arounder than Xuelin V812v2, Hifiman Hm-601 and Fiio X3.
HIGHS and TREBLE:
This is where the extreme clearness of sound display the most his strong and gracile presentation. The treble of Ibasso Dx90 is sparkly and never harsh, details retrieval is hallucinatory and can just be measure by the capacity of your earing range. Everything is there, layers and layers of easy flowing textures can build in a harmonious ensemble without effort, it flow naturally and musicaly, without ever trying to impress the highs excell and go up to top without brightness or artificial sounding. As the amount of details blossom in an airy and vast musical space, highs can feel not enough tweaked for some, the fact is you can hear more if you want, but the neutral signature of Ibasso Dx90 did not extract some specific frequency range to color or energize his sound. Even if it doesn't feel boring at all, the flatness of sound can be too polite for some, more than ever the music player ask for attention to the listener to be granted by his humble complexity. With my Grado that are already details revealing and considered too bright by some the Ibasso should sound dry and perhaps harsh but it isn't the case, and I think this is where the extremely low ''total harmonic distortion'' show the potential of the sound spectrum of extreme cleaness, even more with an amp connect to line out. With High resolution music it is even more perfect. Of all the music player I try, Ibasso Dx90 have the most beautiful and natural sounding high and for once I feel the 17hz-20khz frequency response specs can be really perceive by my hearing (and the hearing of my cats too).
SOUND SUMMARY :
The Ibasso Dx90 have a spacious soundstage with lot of air between instruments, it is above average but less rounded than Xuelin ihifi that use a Wolfson Dac brillantly. It can drive properly your portable headphones and all earphones are easily powered but full headphones of more than 150 Ohm or hard to drive orthodynamic isn't always used at their full potential straight off the player. You should at least use a portable amp and one with a bass boost can really be usefull too. As said, the sound feel serious, the audiophile terminology is for once appropriate to an hifi player, if you don't consider subtle enhancement in the naturalness of sound presentation as the holy grail of your audio quest I don't think this player is necessary for you. Sacd do really show what this player is capable off and you should not listen to MP3 under 320kz as you will think the player hiss while it's due to the poor quality of your music. The sound is heard as the artist in his studio wish it would, everything is discernable and can be picked up by your attention, this player give you bionical ears, seriously! It will suit most type of headphones and earphones, only over detailed or already too bright one will not complement it well.
It make more than one year that I use daily this fascinating player, I use it to plug to my system, my portable amp and to transport it everywhere I go. If you bring with you a batterypack (can use Dx90 while charging) or second battery it will have an infinite autonomy. The only flaw of this player is about the firmware but i'm not really difficult about this and never been an ipod fan, or playlist or whatever custom friendly device and of all the players I own I feel the Dx90 firmware is the most sophisticated with it's very responsive touchscreen. You should note too that the equalizer worth nothing and should ALWAYS be turn OFF. If you want more options with the firmware I advice you to install ROCKBOX to it, will try this soon but never feel the need to be lost in an abondance of options.
All in all, I adore this music player and can say my life will be less musical without it, this is sad but since I have it i'm unable to return to my Ipod touch without finding it annoying and dirty sounding. This player have the magical capacity of making souding all your headphones at their best if they are bellow 100 ohm, even cheap headphones became surprinsingly good sounding sometime with this player, it is a fascinating device that open lot of doors and I strongly advice to every new audiophile to begin with this. As said, when I compare the Ibasso Dx90 to something mass marketed like Ipod touch it is so horrifious how the Ipod is tweaked in the lows an mids that I can't even enjoy music with it anymore, the ipod bass veil everything and lack of cleaness can make distort even good headphones if they are bassy. This is one of the miracle of this player, it bring the best of all your gear.
Anyway, as perfection could not really exist in all perspective, the Dx90 still have firmware bugs that can cause frustrations and insecurity about his longevity, mine crash sometime in some mysterious way that can cause great anguish. For that, this player will not earn a perfect 5 but a still prestigious 4.5 stars.
I purchased the DX90 a week ago. I had found that I was no longer dragging out CDs to listen to music, but at the same time my MP4s on my iPhone were sounding harsh and un-listenable. As a result I was not listening to much music anymore and really missed it. I occasionally listen on headphones but mostly plug into my stereo (Acurus DIA100 and Paradigm Atom Montior v5). The sound from my iPhone was so harsh and clearly missing much of the detail of the music due to compression. My plan is to rip all my CDs to FLAC files and use the DX90 for portable listening as well as in-home listening through my sound system. I read about the DX90 and then purchased it on eBay from someone who had used it very little--he said about five hours.
I can't stress enough the importance of burn-in on this device. When I first heard it I thought I had made a big mistake. It sounded similar to my iPhone. I'm up to 120 hours of burn-in time right now (the manual recommends 400 hours!)--I leave it on all the time, using the provided burn-in cable. The sound has changed incredibly. It sounds very smooth, open, and detailed. My amp tends to be a bit bright, and I find that the DX90 compliments it well by being more mellow. I've read other reviews that say the DX90 is also bright or harsh, but I don't find that to be the case after proper burn-in.
The OS does some quirky things, like repeating a song when I press the skip forward button, but overall seems to be fine. I mostly randomize my playlist, so I just set it to random and go, so the OS is not much of an issue for me.
I have not taken the DX90 out of the house much, so I don't have a good sense of battery life. I plan to purchase a backup battery and always have one fully charged to grab and go as needed.
I have a 128GB micro SD card that I use, which holds all of my music, and I use Windows Media Player's syncing functionality so when I plug the SD into my computer it automatically syncs any new music. I'm using Exact Audio Copy to rip my CDs and find it fairly quick in processing and converting to FLAC.
Now that I hear the complete music again I just can't believe how long I went listening crappy lossy files! So nice to be enjoying music again.