Add support for native internal-DAC playback for Astell & Kern devices.
Problem solved
Allow the Symfonium app to bypass Android’s standard audio mixer and processor and communicate with Astell & Kern’s built in DAC to achieve bit-perfect playback.
Brought benefits
Symfonium would be able to play audio files how they are meant to be played, 16-bit, 24-bit, or 32-bit, allowing the color on the LED volume wheel to correctly reflect what is playing.
Other application solutions
n/a
Device type
Phone
Additional description and context
On Astell & Kern DAPs, the Android OS makes any file that plays through Symfonium go through Android’s audio mixer and not the DAC built into the device, resulting in only 24-bit playback, even for 16-bit files. I’m aware that there are some settings missing under Settings>Playback>Decoding and transcoding on my Astell & Kern (SP3000T) so maybe we just need those settings on our A&Ks. I have attached pictures of my Symfonium missing those previous mentioned settings. I’ve also attached pictures showing how the LED light shows green (which is 24bit playback) for a 16bit song when it should be red, while the built-in music player reflects the correct color suggesting bit-perfect playback. (They are different songs but they were ripped from the same CD, they are both 16bit FLAC files.) Thank you for any feedback!
Apparently Neutron Music Player and USB Audio Player Pro (UAPP) can bypass Android’s mixer for bit-perfect playback (Neutron Music Player specifically says it works for Astell & Kerns), but they are paid and I’d rather not pay for these apps, but perhaps it could help you figure out how to bring that development to Symfonium.
Thank you for the details. I need debug logs from your SP3000T to check the audio capabilities it exposes and the playback path Symfonium selects.
Please update to the latest published version available for your channel and retry. Check the appropriate announcement in the changelog; if Google Play has not approved that release yet, the announcement explains how to get the official APK.
Please enable debug logging, open Settings > Playback > Decoding and transcoding, then play a known 16-bit FLAC through the built-in DAC until you see the green LED. Disable debug mode and upload the logs promptly. Please reply with your app version, SP3000T firmware version, upload description and the time you reproduced it so I can find the right logs.
You can also convince them to send me a device so I add support for it.
I think I uploaded the logs correctly, but let me know if I did something wrong. I did this at around 4:56am Eastern Standard Time or 8:56am UTC. I played a 24bit FLAC followed by a 16bit FLAC. My Symfonium Version is 15.1.0 (127812). My SP3000T firmware is 1.25CM.
I found your upload, thank you. It contains the 24-bit FLAC followed by the 16-bit FLAC on your SP3000T, so the logs came through correctly.
Both tracks use Symfonium’s standard Android audio output path. I can see the format Symfonium sends to Android, but these logs don’t measure the DAC’s final output format or establish how to enable native Astell & Kern access.
Not much I can do without access to those devices, and at their price if they do not send me one it’s hard to justify for now, I’d need to increase the price of Symfonium a lot
