Both the DX’s offer you a coaxial out so you can hook up your DAP to an external DAC but that’s not all. On the latest firmware you can use the DX50 and DX90 as a USB DAC. In theory that is. A quick look at the Head-fi thread immediately shows you lots of owners are having issues with getting the DAPs to work as USB DAC. Unfortunately I am one of them. After a few attempts –even with the latest driver that was only just released- , reboots and a couple of BSOD experiences I abandoned my quest to use the DX90 as USB DAC.
Besides the screen quality, I have nothing to complain about so far at all,I love what they have done but why on earth is it so damn hard to make your DAP work as a USB DAC? It should be easy iBasso. I haven’t had a problem with any of the other Hi Res DAPs when connecting them as USB DAC and I do think they should get this sorted out ASAP.
In general I’m quite pleased with the iBasso User Interface as it is very easy to use. It however can be a bit lagging when changing tracks, especially when using the touch screen to switch songs. Overall it’s not as good as the excellent reference UI from the Astel&Kerns but it do is a step up from the Fiio UI.
The music menu offers you a choice between: Now Playing / Directory / Playlist / All music / Album / Artist and Genre. I’m a big fan of shuffle play and I find myself going to the “All Music” option most of the time. One issue I have with the interface is that when you have shuffle turned on, you will actually never go back to the previous song, you will always get a different song and that’s too bad as I sometimes like to listen to the same song over again. Or sometimes when you click next song and you change your mind? Well too bad, it’s gone. Another downside to me is that there is no “Line Out” setting like with the Fiio and AKs, and you manually have to turn up the volume to 255. Luckily volume goes up fast once you’ve passed 220 on the dial.
The Settings Menu offers a lot of options like EQ, Gapless playback, USB settings, L/R Balance, Digital Filter and many more. Gapless playback is always on in my case and it’s been working pretty well. Some users have reported issues with certain file types but I haven’t experienced any weird behavior yet. In the Digital Filter menu you can choose between a sharp or slow roll-off. Most of the time I have it set to sharp depending on the headphone used and the music I am listening to but the difference in sound to me is rather limited.
Like with all my sources I hardly ever touch the EQ settings. The DX’s offer you an 8 band EQ with 5 presets for pop, rock, classic, dance and bass. Personally I find them to sound best with the EQ turned off but to each his own of course.
In the end the UI is pretty good and it’s pocket friendly as well. Once you’ve chosen your album or shuffle play, it’s very easy to operate the DX without looking at it.
Firmware versions used were 1.5 on the DX50 and the latest 2.1.5 on the DX90. Too bad I couldn’t use the firmware from Lurker. These unit’s aren’t mine (going back to AudioGarden) and I didn’t want to mess around with the FW too much. If you have the DX90 I would certainly check it out as I have read nothing but good about it.
EDIT May 8 2015: Click here to read an update on Rockboxing your DX90
In 2013 I wasn’t too convinced with how the DX50 sounded and to be honest I still am not today. I keep hearing from a lot of people, Nathan included, that the DX50 is supposed to be very silent but my unit certainly is not. It’s even almost as noisy as the Fiio X1 on the headphone out. This noise is only audible on the headphone out though, and not the Line Out. I really hope the noise is my unit being faulty somehow because it’s just too much noise for a Hi Res DAP. The DX90 on the other hand is dead silent with even my most sensitive custom in ear monitors. The way it should be.
I have lots of love for both units for several reasons.
The volume control has 255 steps. It has a huge range and it allows you to set your perfect listening level with all types of headphones. The downside, like I mentioned, is that you can’t go to max volume with one click but I can live with that. Another superb feature of these iBasso’s is the gain stage. I’m not afraid to say that I have hardly ever seen a gain stage that was this well implemented. Depending on the ear- or headphone used you can easily switch to medium or high gain. Sure a lot of units do that but these stages actually make your headphone sound better and they don’t just give you more power. The Beyerdynamic DT770 AE in example doesn’t need medium gain at all but it actually sounds better using medium gain, especially at very low listening levels. That’s the case for a whole lot of headphones in my collection. Both units have a lot of power and of all the DAPs I have tested these are the ones I feel the less need with to use an external amplifier. That means a lot. With the TOTL Astel&Kern players you won’t see me using my Audeze’s straight out of the headphone plug. With the DX50 and DX90 that is no problem whatsoever. And the most important thing is the headphones actually sound great too. I’m listening to Moby as I type using the DX90 and my LCD-XC. That’s on medium gain and at volume level 190. I can assure you it sounds great.
The difference in sound between the DX50 and DX90 isn’t little. Long story short is – it won’t come as a surprise – I’m not a big fan of the DX50 but I seriously love the DX90.
The DX50 has a more in your face kind of sound. Like the player is saying: here’s the sound, like it or not. But it’s just sound. It’s rather dry sounding where I mean it’s not as musical and I’m missing a lot of dynamics. Detail wise it is ok but it’s nothing special either. Same goes for its sound stage. Not the worst by far but not the best either. That doesn’t make the DX50 a bad player but to me it doesn’t sound smooth or musical at all and I find it a rather boring sound to be honest. To me it’s nothing more than OK when comparing it to the DX90. But looking at the price, it’s more than just OK.
The DX90, using the Sabre Chips, is the complete opposite: it has a lot more detail in the bass, mids and treble. It has a sound stage that is a lot wider and deeper and it sounds very musical and dynamic. One of the better DAPs I have listened to. It’s that simple.
Both units have a little bass emphasis and I can live happily with that. They have good body overall and especially the mids are great. Make that superb on the DX90. The 90’s mids are gorgeous and have the perfect amount of body, detail, air and smoothness making them very musical and dynamic sounding compared to the DX50. The strength of these players obviously is in the bass and mids but don’t underestimate the treble. While it’s not the most extended treble ever, it still is very good on the DX90 (less so with the DX50).
The Line Out is good on both units but the DX90 sounds a whole lot better as it has the best DAC section of both players. You will find an external amp is not needed for IEMs at all. For your full sized harder to drive headphones you can use an external amp and your headphones will sound even better but like I said, these DAPs have positively surprised me with their ability to drive full sized headphones. I have tested the LO with Fiio’s E12 & E12A, JdsLabs C5, Cypherlabs Picollo & Duet and even with desktop size amps like the Violectric V281 and the Beyerdynamic A2&A20.
Comparisons, Headphones and Conclusion on Page 3