Considering it’s going through a junky phone dac or Bluetooth earbud dac, convert them to 320 mp3 and store that on ya phone.
DON’T. Use 160kbps Opus instead, all modern phones should support it. You can halve the size of your library while still enjoying the quality of 320kbps mp3.
How’s the tagging when converting over to Opus?
I assume it supports the basics like Album and Artists but what about tags like embedded lyrics or ReplayGain?