Semplice Version 1.0 - Now Available for Download
It's only three months late (!), but Semplice, the all-new, all-singing, all-dancing FLAC manager for Linux, Windows, macOS and Raspberry Pi, has just been released and is available for download, with instructions for doing that available from its web page.
In a nutshell, Semplice allows you to (1) tag FLACs; (2) apply volume boosts to FLACs; (3) concatenate per-track FLACs into single-file, whole-composition SuperFLACs; (4) split SuperFLACs back out into being per-track FLACs; and (5) convert audio files from and to about 7 or 8 different audio codecs (so, FLAC to MP3, for example; or SACD's DSF to super hi-res FLACs). [...]