Hi - I’m new to roon so apologies if this is a silly question. When I listen music on my Sonos the “Signal Path” shows me a graphic that seems to indicate nothing is being converted but when listening in my Android tablet it shows me an intermediate dot and it shows a processing speed that I assume is how fast is processing the mp3 (mp3 44.1Khz 16bits 2ch 320kbps) to a format compatible with the tablet. The question is how kind of audio file is compatible in Android (6.0) to avoid this. Is there a list that show this for Android / Win / etc?
Android OS is limited to 16/48. All audio on Android goes through the OS Mixer so it will never be bit perfect. The only way is to run special USB software programs with a usb cable to an external DAC. At that point you can get higher resolution / bit depth.
Thanks for your response, so if it support 16/48 … why does it need to process a 16bits 44.1Khz file? maybe I misunderstood what you were trying to say. I more familiar with video formats (plex) than audio formats :).
Because it only supports 16/48, not up to 16/48
Got it. Thanks.
So found this in: https://developer.android.com/guide/topics/media/media-formats.html
(Android 3.1+) Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler does not include a low-pass filter). 16-bit recommended; no dither applied for 24-bit.FLAC (.flac) only
I’m testing with a FLAC file (44.1KHz 16bit 2ch) and still see a green dot. I’d expect to see not processing at all since it seems it should handle it according with the android info.
Any OS Mixer is considered not bit perfect because the OS is resampling the signal to include it in the OS output. This is how your phone can beep while you are listening to music, or make any other notification sounds. Same for Windows, Mac. To ensure bit perfect playback you have to be able to enable exclusive modes which Android does not have in the base OS.
Thanks for the detailed answer.
You can get around this by using an external USB driver, an OTG USB cable and a USB DAC. I’ve setup a AQ Dragonfly as a test and it worked. However, since the Dragonfly takes power from the USB port, it drained the phone pretty fast.
Generally, I don’t worry about it as I love using my phones as mobile endpoints. The music still sounds good. I love taking a phone and a bluetooth speaker and going outside (but still in WiFi range) and blasting music from Roon/Tidal.
@Rugby which external USB driver are you using with Roon?
Sorry for the bump but I’m in the same situation. Which external usb driver can I use with samsung s7 and dragonfly red?