Test files can be obtained e.g. at High Definition Audio Test Files. Then of course you need a way to connect your phone's output into the computer's input. And you have to make sure that the input works with high resolution.dmitrykos wrote: ↑Tue Jan 12, 2021 8:15 pm[...] you can employ really effective method which works for all devices:
1. Use Audacity (https://www.audacityteam.org) audio app
2. Create sweep tone for the range of frequencies you wish to test
3. Play sweep tone with Neutron or any other music app and Record it with PC with Audacity at for example 192 kHz frequency
4. Do spectrum with Audacity for the recording and see what frequencies are available
I tried it out: I connected the headphone jack of my S9 with a standard cable to the microphone jack of an old linux pc. Recording with Audacity didn't work well, though, I didn't get the high frequencies across, probably due to some issue with Audacity being unable to set the sampling rate for the soundcard. I used another linux command ( arecord ) for that, and I could make sure that using 88.2 kHz sampling rate really brings up to 40 Khz to the analog output.
So here's how playing in Neutron looks :
This is the test file :
This is the command for recording :
And this is what has been recorded :
All frequencies, especially those above 24 kHz, can be found, so that's successful high-res-audio. And this is how a failed test would look like :
If there are no frequencies above 48 kHz / 2 = 24 kHz then you didn't verify high-res-audio.