Impressions mainly based on firmware 1.11.140 and before.
Nice unboxing experience.
Protectors for the screen and back included but not applied (thin plastic foil back protectors are already applied but already show some scratches out of the box), which is a little sad.
High quality, soft yellow leather case included (nicely colourful, visual contrast to the black, silver and grey - however, I would have preferred if a pleather, silicone or plastic case were included with the real leather one offered as a separate accessory).
I like that the volume control wheel is noticeably slimmer in profile compared to the DX200 and DX150. Grippy and easy to operate (to a lesser degree when the DX220 is in the case, but it's still rather easy).
USB-C quick charging.
apt-X Bluetooth implemented since release.
MQA support for those who feel like they need it.
Over-the-air firmware/OS updates work since release (no PC required anymore for updating the firmware).
Added additional, third gain mode for especially sensitive in-ears.
Visual upgrade from DX200 (and in my opinion also DX150) while still sharing visual similarities. Perhaps a bit bland, design-wise.
Black glass on the rear as well as bundled AMP1 MKII amplifier module looks nice.
High build quality.
The physical play/pause button doesn't have a tactile dot anymore.
Compatible with all previously released amplifier modules (just like the DX200 and DX150). No screwdriver included.
Gapless playback works perfectly, just as it should, with FLAC files.
Actual digital optical output (needs to be activated in order to work) as well as coaxial output.
Bundled protective case makes the screen's far top and side borders
somewhat difficult to reach (especially the Android drop-down quick
settings).
Despite the RAM and processor speed, animations, navigation and inputs aren't always as fluent as on a low-priced Xiaomi smartphone with lesser specs. Very fast and responsive most of the time, though, however sometimes with a slight lag.
Gets quite hot when in use.
Gets quite hot when in use.
Pretty fantastic screen (full HD; excellent pixel density and viewing angles; actual screen thankfully rectangular and without rounded corners; covers almost the entire front; glass has rounded edges wherefore it is smooth to hold, touch and operate) except for that the colour saturation is probably a bit too high.
GUI:
All impressions mainly based on firmware 1.11.140 and before.
Android 8; iBasso's launcher is visually mostly similar to stock Android, which is a good thing.
(There's also an additional OS (with disabled wireless options and apps; basically just a pure music player) one can boot into, however it is far more basic and less responsive than iBasso's player app in Android OS mode. In addition, it only offers 100 volume steps.)
No Google Play Store, but no big issue for free apps as the already
installed "APKPure" app serves as an alternative app store and also
keeps the installed apps up to date. The YouTube ap does not work, though.
Automatic screen rotation (on supported apps and if enabled).
Completely redesigned player app (with parametric EQ and finally a search feature). Well-organised and -structured; also finally sorts by the "Album Artist" tag by default in "Artist"
library view (finally - which makes it one of the fewer players on the
market that base their music library view on this more logical tag).
Simply put, the new player app is excellent for music playback and offers a well-organised library.
Parametric EQ (6 bands, +/-20 dB, 25 Hz - 20 kHz, Q 0.3 - 20) definitely nice to have but not as easy to use or intuitive or responsive as the one on my RME ADI-2 DAC (that shows an absolute adjusted filter curve whereas the iBasso's only shows an overlay of all filters).
Neat: shows sampling rate in status bar for music playback outside of the native iBasso player app (doesn't show the bit rate, though).
WiFi and Music Streaming:
Unlike on the DX200, I'm not getting any WiFi interference noise or clicks from the DX220 when streaming music or when the WiFi is activated and connected to my router.
Music streaming works well and without buffering.
Sound:
Fully balanced internal architecture always active.
Potential audible pops during sample rate changes.
Unfortunately, like on many audio devices, there's (loud) crackling/popping while inserting/unplugging the headphone's 3.5 mm connector from the DX220 (louder compared to many other devices). A well-made relay-based delay/protection, something that's present on my RME ADI-2 DAC and works fantastically, is something that I therefore somewhat miss on the DX220 (as that crackling/popping is definitely loud with sensitive in-ears (sure, I usually don't have my in-ears inserted when I unplug/plug in the 3.5 mm connector, but it's nonetheless something I do not feel comfortable with as it's loud noise)).
Seven digital filters to choose from.
Everything below is based on the bundled AMP1 MKII amplifier module and its 3.5 mm headphone output.
Volume Control:
150 steps (system-wide) in Android OS; 100 steps in Mango OS. Three gain stages.
No accelerated volume attenuation when turning the wheel quickly.
Listening quietly is definitely possible, even with in-ears as sensitive as my Campfire Audio Andromeda.
Therefore ultimately not as precise and quiet as my beloved iBasso DX90 (256 volume steps with a scaling of 0.5 dB per step over the entire adjustable range), but still good and somewhat better than some of the digital audio player competition (such as devices from Cowon, HiFiman, FiiO or Echobox Audio) that often don't allow for quiet listening with very sensitive in-ears and/or have got coarser attenuation steps in the low adjustment range.
Frequency Response (3.5 mm Headphone Output, no Load, Filter 1 ("Fast Roll-Off (Linear)")):
As flat as expected and as it should be.
Output Impedance / complex Load Frequency Response/Frequency Deviation (3.5 mm Headphone Output, Filter 3 ("Fast Roll-Off (Minimum)"); Load: Ultimate Ears Triple.Fi 10):
Based on the frequency deviation, the calculated output impedance is below 0.5 Ohms, which backs up the "around 0.3 Ohms" that iBasso state and is better than most, if not all, Apple iPhones.
That said, that's a very good value and the DX220 is therefore fully capable of driving low-impedance multi-BA in-ears without any audible frequency response deviation.
Hiss Performance (3.5 mm Headphone Output):
Using my extremely sensitive Campfire Audio Andromeda, there is only mild audible hissing when listening quietly or in quiet passages. Using my somewhat less, but still nearly-extremely sensitive Shure SE846 or Ostry KC06A, the hiss is only barely there and just a little above the audible threshold when one is in a quiet environment and listening very quietly or to empty audio files and in quiet passages of the music.
This makes the DX220 one of the best devices (with at the same time low output impedance) on the market when it comes to hiss performance combined with extremely sensitive in-ears, and even an improvement over some of their past devices, however iBasso's own (and unfortunately discontinued) DX90 fares even somewhat better in this regard (even audible closer to no hiss at all with my Andromeda), and only beat by my RME ADI-2 DAC that is completely hiss-free (IEM output) as well as my Leckerton UHA-6S.MKII (when set to low gain).
So yeah, very good, but just a little shy of excellent, and better than most, if not all, iPhones.
Subjective Sound Perception (3.5 mm Headphone Output):
The subjective sound is just as one would expect from any well-made, flawlessly designed audio devices - neutral, transparent and clean.
Driving low impedance, high sensitivity in-ears leads to the same impression, thanks to the DX220's very good hiss performance and otherwise very good measurements, wherefore the sound remains clean and transparent.
Conclusion:
Pretty fantastic screen. Very good media library (with correctly sorted albums and artists, a handy search feature and a folder browser).
Very good in most areas (and generally better than an iPhone for most audio-related things)? Absolutely yes.
Excellent or perfect? No (there are still some areas where the DX90 is ahead).