Hi-Res Masters (typically 24-bit/96kHz or higher) provide a wider soundstage. In tracks like "Decode" or "Misery Business," this allows you to hear the separation between the drums, bass, and guitars that often gets muddied in low-quality streams.
To truly appreciate these FLAC files, your hardware needs to match the software: Paramore - Hi-Res Masters -FLAC Songs- -PMEDIA- ---