GUI.

3kT UI update, as part of A&K 4^th-gen interface, is nearly identical to 3k.  Therefore, this section is almost the same as my 3k review except for the addition of an AMP menu (to switch between OP/Hybrid/Tube and select 3 levels of Tube current) and the VU meter interface.  Nevertheless, I think it is still worth covering it below since some people might not be familiar with all the details.

When it comes to A&K DAPs user interface, once you are familiar with one, you will feel at home using the rest because they share the same interface, down to their smaller 3.6” display SR25 and SR35 models.  There have been small updates here and there, like a Floating Back button on a screen or playback controls when you swipe down the notification bar while running apps.  A few other Android-related features were added in the past, but just like 3k, 3kT takes it to the next level with a newly updated 4th-generation interface that has improved ergonomics.

When you start the player, the greeting screen has a carousel where you can swipe through and access your songs in alphabetical order.  It’s a fun way to view the song’s artwork along with other info, and it is very fast as you swipe through it.  As you swipe right->left above or below the artwork of the song, you have a Media Category Browser screen to view your Songs, Album, Artist, Genre, Playlists, Folder, Favorite, MQS, CD Library, and then Settings and Category change to rearrange the order of the categories above as well as being able to disable home screen carousel.  Btw, when enabled, the Home button at the bottom of the screen takes you to this home screen carousel, and every time you touch the Home button, it randomly brings up another song.  I wish there would be a way to assign a different screen to the Home button, but if you disable the Home-carousel view and rearrange Media Categories, touching the Home button will always bring you to the first selection in that list.  I know, it is probably hard to visualize it by just reading this, but it is a lot of fun playing with it, especially since GUI is quite responsive.

At the bottom of the screen, you have 4 shortcut buttons, a Home button which I already talked about above, the brand-new VU meter button, Services (for easy access to all the apps), and a Back button, which is no longer floating while covering the screen, it is dedicated and always visible button at the bottom of the screen.   Above it in the Main Home screen, you have a Playback control strip with the name of the currently playing song/artist and Play/Pause and Skip controls.  Tapping on it or swiping it up brings up a familiar Playback screen window where the embedded artwork occupies the top half of the screen and tapping on it expands the view and shows lyrics if one is available.  Swiping this window down brings you back to the main home screen.  Below it you get a summary of the song format (bit depth, sampling rate, file type) and a shortcut to tag the song as Favorite or another 3-dot shortcut with additional functions.  Then, you have a song artist/title and a scrub bar to advance through the song.  Playback touch controls are underneath that along with Play mode controls.

Swiping down the notification bar gives you access to shortcuts to access various controls which you can toggle on/off or long press to get to their corresponding Settings screen.  Here you have Wifi, Bluetooth, DAR (Digital Audio Remaster), EQ, AMP selection, Crossfeed, AK Connect, Line Out, Wheel Lock, and Settings.  These are default shortcuts, and in Settings under Notification Panel, you can access Car Mode, ReplayGain, AK File Drop, and Gapless, as well as being able to rearrange the order of Notification shortcuts.  At the bottom of the open notification bar, you also have Brightness control.  The full Settings window has more controls, partitioned into sections.  Other controls you can find here are to select Bluetooth Codec, Roon Ready switch, AMP control, EQ, Crossfeed, DAR setting, change DAC filters, L/R balance, Gapless, ReplayGain, Line Out, and Playback setting.  Other usual controls for A&K CD Ripper, USB Mode, Audio output format, S/PDIF Conversion, Car Mode, setting Volume limit, enabling Double-Tap Screen to wake, enabling/disabling LED indication.  And the typical date/time change, language and keyboard selection, timer settings, FW update, System info, and System Reset.

EQ is a big deal for some audiophiles, and here it hasn’t been changed.   There are no genre-specific presets, but you have A&K collab IEM-specific presets for Odyssey, AURA, and NOVUS, and you can add many custom EQ presets.  EQ interface has two modes: Main and Advance.  In the Main, you have standard Paragraphic EQ sliders for 20 bands (30, 45, 60, 90, 120, 180, 250, 380, 500, 750, 1k, 1.5k, 2k, 3k, 4k, 6k, 8k, 12k, 14k, and 18k) where you can either slide the bar or use a precise 0.1 adjustment, as well as scrolling through available frequencies.  As you adjust, it gets reflected in the lower right corner, showing the overall shape of EQ.  Switching to Advance turns EQ adjustment into Semi-Parametric EQ with a full GUI view of EQ shape where underneath you have FREQ band selection (a choice of 20), Gain selection in 0.1 and 0.01 steps, and Q bandwidth.  Since the band’s frequency is fixed, I consider this to be semi-Parametric EQ.

The new updated GUI is a step forward, more intuitive, and faster.  We are still dealing with a closed Android interface, but these changes bring it closer to the Android experience with an always visible navigation bar at the bottom where you have access to Streaming services, Home Screen (which you can set to a default view), and Back button for easier app navigation.  Double-Tap screen to wake is very useful so you don’t have to press power/volume wheel every time you want to turn the display on.  Some might find Crossfeed and Replay Gain useful, or the DAR (Digital Audio Remaster) upsampling function to PCM or DSD.  I enjoyed the new VU-meter screen, especially its Full-Screen mode option which removes the notification bar at the top and navigation buttons at the bottom, giving you a clean analog screen look.

Open APP Service.

Open APP Service is implemented in all A&K Android-based DAPs, including SP1000 SS/CU, SP1000M, SE100/180/200/300, SR35/25, SP2000 SS/CU, SP2000T, SP3000, and SP3000T. More info can be found here where Astell & Kern goes into more detail about it.

While Astell & Kern offers a built-in Tidal service (without off-line storage support), for a long time their customers have been asking to add other popular streaming services, especially since their DAPs run on Android though heavily modified closed OS without access to Google Play.  Now, all their latest DAPs have many whitelisted open apps they can run, such as Tidal, Amazon Music HD, Apple Music, Qobuz, Spotify, and many others.  For convenience, when you go to Services, you have an Open Service tab with installed apps and a Download tab with a list of available apps you can download and install.  While you can’t install every app you desire, in a way it’s a blessing for a manufacturer to keep DAP performance optimized since you don’t have to worry about customers installing and running other unstable apps.  Plus, it also guarantees the compatibility of these apps with the DAP.

Page 3 – Sound Analysis, Comparison.
Page 4 – Pair up, Wired/wireless connections, and Conclusion.