WAV is more widely supported, but lacks basic features like tags. Use LossyFLAC (PCM audio processed with LossyWAV, and stored in a FLAC container) for lossy archival. The filesize won't be as small as you get with other lossy codecs, but it's small enough. The trade-off is that you're sticking with PCM audio which, means you can convert between lossless audio formats without quality loss. This helps future-proof your lossy collection. Use MP3 for portable devices. It has the worst audio quality of all the popular lossy codecs, but it sounds good enough. The trade-off is that it's the most widely supported lossy codec, and has the lowest CPU usage (making it the most battery friendly). Use Opus for portable devices with extremely limited space.
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