It has been a busy stretch since SP4000 AKCFW 0.77.6. I am now on the sealed 0.80.12 Engineering Candidate, with work on 0.81.0 about to begin.
Since 0.77.6, several major pieces have landed:
AutoEQ with searchable headphone measurements and integration with the native EQ system.
Sound Studio, including Personal Sound, AudioSphere and Acura.
A unified shared-gain system so EQ and Sound Studio effects cooperate instead of stacking attenuation unpredictably.
A refined playback-format indicator for PCM, native DSD and DAR processing.
Correct handling of USB DAC mode, including clearing or hiding information that cannot be reported reliably.
Headphone volume protection, lowering volume to 30 after disconnecting a 3.5 mm or 4.4 mm headphone.
A redesigned Classic Audio boot animation and plenty of smaller UI, recovery, component-label and reliability improvements.
The next ambitious project is a Headphone / IEM Preset Manager.
Because the SP4000 can detect when headphones are connected, the idea is to present an optional native A&K-style menu containing saved listening profiles. A preset could recall volume, DAR mode, High Driving Mode, EQ or AutoEQ profile, Personal Sound, AudioSphere and Acura settings.
The player cannot identify an individual headphone by impedance, so it will never guess. You will explicitly select the correct preset—or create a new one—when connecting your headphones or IEMs. Think Personal Sound meets Sound Studio, with quick controls and no unnecessary Android clutter.
Early concepts, still subjected to change:
After that, the remaining road is becoming much shorter:
Complete the Classic and Pure Audio firmware split
Finalize safe profile switching and application-state handling
Complete packaging and installation workflows
Prepare Companion support
Begin controlled public beta testing
There is still work ahead, but SP4000 AKCFW is moving beyond isolated tweaks and becoming a genuinely cohesive music-focused operating environment.
And yes—public testing is finally beginning to appear on the horizon. 😉